learning from picture books: the effect of naming on
TRANSCRIPT
University of Calgary
PRISM: University of Calgary's Digital Repository
Graduate Studies The Vault: Electronic Theses and Dissertations
2012-10-01
Learning from picture books: The effect of naming on
infants’ transfer of nonobvious properties
Khu, Melanie
Khu, M. (2012). Learning from picture books: The effect of naming on infants’ transfer of
nonobvious properties (Unpublished master's thesis). University of Calgary, Calgary, AB.
doi:10.11575/PRISM/26741
http://hdl.handle.net/11023/244
master thesis
University of Calgary graduate students retain copyright ownership and moral rights for their
thesis. You may use this material in any way that is permitted by the Copyright Act or through
licensing that has been assigned to the document. For uses that are not allowable under
copyright legislation or licensing, you are required to seek permission.
Downloaded from PRISM: https://prism.ucalgary.ca
i
UNIVERSITY OF CALGARY
Learning from Picture Books:
The Effect of Naming on Infants’ Transfer of Nonobvious Properties
by
Melanie Khu
SUBMITTED TO THE FACULTY OF GRADUATE STUDIES
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER
OF SCIENCE
PROGRAM
PROGRAM IN CLINICAL PSYCHOLOGY
DEPARTMENT OF PSYCHOLOGY
CALGARY, ALBERTA
SEPTEMBER 2012
© Melanie Khu 2012
ii
Abstract
The present study investigated whether naming would facilitate infants’ transfer of
information from picture books to the real world. Independent groups of 18- and 21-month-olds
were shown a picture book that taught them a novel label for a novel object. Infants then saw a
second picture book in which an adult demonstrated how to elicit the object’s nonobvious
property. Accompanying narration described the pictures using the object’s newly learned label.
Infants were subsequently tested with the real-world object depicted in the book and a different-
colour exemplar. Infants’ performance on the test trials was compared with that of infants in a no
label condition. The odds of attempting to elicit the object’s nonobvious property with the exact
object depicted in the book were almost 2.5 times greater for infants who heard the label
compared to infants who did not. Naming did not predict test performance for the different-
colour exemplar.
iii
Acknowledgements
I would like to thank my supervisor, Dr. Susan Graham, for her encouragement and
guidance over the course of this project. When faced with setbacks, her enthusiasm and eternal
optimism were much appreciated. I would also like to express my thanks to my committee
members, Dr. Suzanne Curtin and Dr. Suzanne Hala, as well as my external examiner, Dr. Karen
Benzies. I am grateful to my lab mates, Jared Berman, Elisea DeSomma, Heather MacKenzie,
Vanessa Schell, Ena Vukatana, and Michelle Zepeda, for making the Language and Cognitive
Development lab much more than just a research space. Special thanks to my ‘buddy’ Sarah
Collins, who has been an invaluable resource over the past couple years, and to Dr. Jeany Keates,
for her contributions to the project.
I would like to express my gratitude to the parents and children who took the time to
participate in my study. I am also grateful to the Curtin family for their generous financial
support. I would also like to acknowledge the financial support provided by NSERC through an
operating grant awarded to Dr. Graham.
Finally, I could not have made it through the past couple years without the members of
TSF - Cameron Clark, Jennifer Ference, Leanne Quigley, and Igor Yakovenko - I am so happy to
have been able to share this experience with all of you. I am also thankful to my parents, Mindy
and Ben, my sisters, Lauren and Vanessa, and to my extended family, especially my
grandparents, Mervin and Debby, for their continued love and support.
iv
Table of Contents
Abstract ............................................................................................................................... ii
Acknowledgements ........................................................................................................... iii
Table of Contents ............................................................................................................... iv
List of Tables ..................................................................................................................... vi
Introduction .........................................................................................................................1
The Development of Pictorial Competence .............................................................3
Infants’ Understanding of the Symbolic Nature of Pictures ....................................4
The Effects of Naming .............................................................................................7
The Present Study ....................................................................................................8
Method ...............................................................................................................................11
Participants .............................................................................................................11
Materials ................................................................................................................12
Labeling Phase ...........................................................................................13
Label Comprehension Phase ......................................................................14
Nonobvious Property Phase .......................................................................14
Test Phase ..................................................................................................15
Procedure ...............................................................................................................15
Labeling Phase ...........................................................................................16
Label Comprehension Phase ......................................................................17
Nonobvious Property Phase .......................................................................18
Test Phase ..................................................................................................18
Coding and Reliability ...........................................................................................19
v
Results ................................................................................................................................20
Object Labels .........................................................................................................21
Nonobivious Properties ..........................................................................................21
Target Actions ............................................................................................21
Examination Time ......................................................................................27
Discussion ..........................................................................................................................29
References ..........................................................................................................................38
Appendix A: Materials – Object Sets ................................................................................45
Figure A1. The box object set ................................................................................45
Figure A2. The light object set ..............................................................................45
Appendix B: Materials – Pictures from the Picture Books ................................................46
Figure B1. Pictures used in the labelling and label comprehension phases ...........46
Figure B2. Pictures used in the nonobvious property phase (box target) ..............46
Figure B3. Pictures used in the nonobvious property phase (box non-target) .......47
Appendix C: Dialogue for the Label and No Label Conditions ........................................48
Appendix D: Interview Questions .....................................................................................52
Appendix E: Supplemental Tables .....................................................................................53
Table E1. Infant demographic information as a function of age and condition ....53
Table E2. Maternal and paternal education as a function of condition .................53
Table E3. Extension Trial: Logistic regression analysis ........................................54
Table E4. Predictors of test performance on the extension trial ............................54
Table E5. Generalization Trial: Logistic regression analysis ................................55
Table E6. Predictors of test performance on the generalization trial .....................55
vi
List of Tables
Table 1. Extension trial: Learning as a function of condition and age group. ...................23
Table 2. Generalization trial: Learning as a function of condition and age group ............23
Table 3. Extension and generalization trials: Mean proportion examination times for the
target object by condition and age group. ..........................................................................28
1
Learning from picture books: The effect of naming on infants’ transfer of nonobvious properties
In Western societies, picture books are amongst the most common symbolic media that
infants and young children encounter in their daily lives. Over the second year of life, infants in
these cultures come to spend considerable time in shared picture book reading interactions with
their parents (Gelman, Coley, Rosengren, Hartman, & Pappas, 1998; Karrass, VanDeventer, &
Braungart-Rieker, 2003; Payne, Whitehurst, & Angell, 1994). For example, in a recent large-
scale survey, parents reported spending an average of 25 minutes per day reading with their 6- to
23-month-old infants (Rideout, 2011).
It is widely assumed that infants, like older children, learn about the world from these
picture book interactions. Previous research has established that, by preschool age, children
understand the referential nature of pictures and will use them both as symbols and sources of
information about the entities they represent (e.g., Callaghan, 1999, 2000; Callaghan & Rankin,
2002; DeLoache, 1991; DeLoache & Burns, 1994; Harris, Kavanaugh, & Dowson, 1997). For
example, by 4 years of age, children can learn new biological facts from picture books and
transfer this information to real animals (Ganea, Ma, & DeLoache, 2011). Although there is clear
evidence that preschoolers can transfer knowledge acquired from a picture book to the real
world, research conducted over the past decade suggests that this task may, in fact, pose quite a
challenge for young infants. First, in order to use pictures symbolically, infants must understand
that pictures are not simply interesting artefacts in their own right, but that they represent things
other than themselves – a concept known as dual representation (DeLoache, 1987, 1991;
DeLoache, Pierroutsakos, & Troseth, 1996). Second, to transfer information from picture books
to the real world, infants must overcome the perceptual differences between books’ two-
dimensional (2D) depictions and the three-dimensional (3D) real-world objects that these
2
depictions represent. Thus, the challenges inherent in this task raise the possibility that infants do
not learn as much from parent-child picture book interactions as has generally been assumed, and
that their ability to transfer this knowledge to the real world may be fairly limited.
Despite the potential challenges, there is evidence that infants as young as 18-months of
age possess a nascent appreciation of the symbolic nature of pictures (e.g., Ganea, Bloom-
Pickard, & DeLoache, 2008; Ganea, Allen, Butler, Carey, & DeLoache, 2009; Keates, Graham,
& Ganea, in revision; Preissler & Carey, 2004; Simcock & DeLoache, 2006), and that under
ideal circumstances, they can transfer knowledge from depicted to real-world objects. However,
it appears that this ability is somewhat tenuous. That is, young infants’ ability to treat pictures
symbolically is vulnerable to disruption by a number of external factors, including properties of
the depictions (e.g., black and white line drawings vs. colour photographs), complexity of task
demands (e.g., learning an action sequence vs. learning an object name) and similarity between
encoding and test conditions (e.g., slight differences between depicted and real-world objects vs.
an exact match). Given that conventional picture books do not always present information in a
manner that facilitates transfer (e.g., many contain drawings rather than photographs), and that
objects encountered in the real world are rarely identical to those seen in pictures books, it is
reasonable to assume that young infants might experience difficulty transferring information
from picture books to the real world following typical, day-to-day picture book interactions.
Understanding the conditions under which infants might demonstrate more robust
learning from picture books is important because, like other symbolic media, picture books
enable infants to indirectly acquire information about the world. Accordingly, identifying ways
to enhance infants’ ability to transfer knowledge from pictures books would afford them vastly
greater opportunities for learning. The present study was designed to investigate the effect of
3
linguistic cues, specifically object names, on infants’ transfer of information from picture books
to real-world objects.
The development of pictorial competence
In order to successfully use a series of pictures presented in a picture book as a source of
information, infants require pictorial competence - the ability to perceive, interpret, and
understand the nature and use of pictures (DeLoache & Burns, 1994; DeLoache et al., 1996;
DeLoache, Pierroutsakos, & Uttal, 2003). Even very young infants demonstrate some
appreciation of the relationship between pictures and the objects they depict, although a more
complex understanding is emergent over the second year of life. Specifically, before their first
birthday, infants can recognize the correspondence between, and also discriminate between, real
3D objects and their 2D pictorial representations (DeLoache, Strauss, & Maynard, 1979; Field,
1976; Rose, 1977), even when these representations do not literally depict the 3D object
(Jowkar-Baniani & Schmuckler, 2011). Despite infants’ early ability to perceive the difference
between pictures and the objects they depict, there is evidence that younger infants do not
understand the nature of pictures and lack an appreciation of how pictures differ from their
referents. For example, 9-month-olds will manually explore depicted objects by patting, rubbing,
and grasping them as they would the real objects (DeLoache, Pierroutsakos, Uttal, Rosengren, &
Gottlieb, 1998; Pierroutsakos & DeLoache, 2003). By 19 months of age, however, infants’
behaviour towards pictures shifts from manual exploration to referential actions such as pointing
and labelling. A similar decline in manual behaviours was reported between the ages of 6 and 18
months (Callaghan, Rochat, MacGillivray, & MacLellan, 2004). DeLoache and colleagues
(1998) have suggested that the decreasing tendency to manually explore pictures may indicate a
4
nascent appreciation of pictures’ representational status (i.e., that pictures represent things other
than themselves).
Infants’ understanding of the symbolic nature of pictures
Support for the notion that infants begin to understand the symbolic nature of pictures
over the course of their second year comes from studies demonstrating that infants as young as
15-months of age extend newly learned labels from depicted objects to their real-world referents
(Ganea et al., 2008, 2009; Preissler & Carey, 2004). In one such study, Ganea and colleagues
(2008) taught infants a novel word (e.g., “blicket”) for one of two novel objects (i.e., target and
distractor), in the context of a picture book interaction. At test, infants were presented with the
real objects depicted in the book (i.e., real target and real distractor) and asked to indicate which
object was the blicket. Both 18- and 15-month-olds correctly identified the real-world object
(i.e., target). Importantly, it appears that infants’ pictorial understanding is not merely
associative. That is, when given a choice between the exact picture that had been used to teach
infants the novel label, and the real object it depicted, 18- and 24-month-old infants
overwhelmingly selected the real object alone or the real object and the picture (Ganea et al.,
2009; Preissler & Carey, 2004). If infants were merely associating the label with the picture with
which the label was paired, then infants should have chosen the picture alone. The findings of
these studies suggest that by at least 18 months of age, infants appreciate that a label applied to a
depicted object refers equally to an object in the real world.
Further support for infants’ emerging appreciation of the symbolic nature of picture-
referent relations comes from studies demonstrating that young children will imitate target
actions on novel real-world objects following a picture book interaction (Simcock & DeLoache,
2006, 2008; Simcock & Dooley, 2007; Simcock, Garrity, & Barr, 2011). For example, one such
5
study demonstrated that, following a picture book interaction in which a depicted action
sequence is used to construct a novel object, 18-, 24-, and 30-month-old children will re-enact
the novel action sequence with a set of real objects (Simcock & DeLoache, 2006). Although the
infants were generally able to learn a novel action sequence from the picture book, their
performance was influenced by a number of factors, including the iconicity of the pictures, and
the similarity between context or stimuli at encoding and test. These effects were especially
pronounced for the 18-month-old infants, who experienced difficulty imitating from the picture
books when there was a discrepancy between conditions at learning and conditions at testing
(Simcock & Dooley, 2007), as well as when the pictures’ realism was reduced relative to the
referent (Simcock & DeLoache, 2006). Despite 18-month-olds’ attenuated performance relative
to their slightly older peers, these studies provide evidence of an early emergent symbolic
understanding.
A recent study by Keates and colleagues (in revision) provided an important extension to
the literature by examining whether infants can learn about depicted objects’ hidden properties
and subsequently transfer this knowledge to the real world. In the context of a picture book
interaction, 13-, 15- and 18-month-old infants were shown a series of pictures. The pictures
depicted an adult performing a target action on a novel object in order to elicit the object’s
nonobvious property (e.g., pushing on the top of a toy to make it light up) and exploring a
distractor object. Infants were subsequently presented with the two real-world objects depicted in
the book. Infants in all three age groups expected the real-world target object to have the
nonobvious property (e.g., lighting up when pushed) as indicated by their attempts to elicit this
property (e.g., pushing on the top the toy) with the target, but not the distractor, object. Thus,
6
there is evidence that infants as young as 13-months of age can learn about object properties
from picture books and transfer this knowledge to the real world.
There is, however, an important caveat to the Keates et al. (in revision) findings.
Although 13- to 18-month-olds as a group transferred nonobvious object properties from
pictures to real-world objects, approximately half of infants in the experiment did not attempt to
elicit the nonobvious properties. This suggests that the ability to learn from picture books is still
relatively tenuous during this developmental period. Yet, such a conclusion conflicts with the
robust learning demonstrated in research using word-learning tasks to examine infants’ ability to
transfer information from pictures (e.g., Ganea et al., 2008, 2009; Preissler & Carey, 2004). For
example, in the study by Ganea and colleagues (2008), 80% of the 18-month-old infants tested
learned the name of the depicted novel object and extended that name to the object’s real-world
referent. To reconcile these discrepant findings, it is important to consider differences in task
complexity, that is, the differences in processing demands and cognitive steps involved.
In the picture induction task used by Keates et al. (in revision), infants were required to
do the following in order to learn from the picture books and to extrapolate that learning to the
real world: (a) attend to the book’s pictures and narrative; (b) encode representations of the
depicted object, its nonobvious property, and the specific action that elicited the nonobvious
property; (c) retain these features in memory; (d) identify a real-world object that matches their
mental representation of the previously encountered depiction; (e) bring to mind knowledge
about the object’s nonobvious property and how to elicit this property; (f) plan and execute the
target action. In contrast, to learn a novel label for a depicted object and transfer that learning to
a real-world object, infants were only required to encode and retain one representation (i.e., the
depicted object and its label). As well, in the word-learning studies, infants either had to point to
7
or select the appropriate real-world object to demonstrate their learning, rather than having to
perform a specific target action. Thus, task complexity and associated processing demands may
be responsible for the apparent difference in infants’ ability to transfer knowledge from depicted
to real-world objects.
The effects of naming
There is evidence that providing a name for depicted objects to infants in their third year
enhances their appreciation of depictions’ symbolic status (e.g., Preissler & Bloom, 2007;
Callaghan, 2000). For example, 2.5-year-olds succeeded in identifying depicted objects’ real-
world referents only when their labels were known or when the depicted objects were labelled
(Callaghan, 2000). Labeling has also been found to facilitate categorization, ostensibly by
increasing the salience of object similarities (Waxman, 2008). Infants as young as 12 months of
age will use shared object names to determine whether two objects belong to the same category,
and continue to do so even when objects share minimal perceptual similarity (e.g., Booth &
Waxman, 2002, 2003; Graham, Kilbreath, & Welder, 2004; Keates & Graham, 2008). Thus, a
review of previous literature would suggest that a label should provide infants with a cue to both
the similarity between depicted and real-world objects, as well as the depictions’ symbolic
function.
A question that emerges from these findings is whether teaching infants a label for a
novel object might help them to transfer information about that object from a picture book to the
real world. Keates (2010) sought to address this question by providing a name for a depicted
object while concurrently teaching them about the object’s nonobvious property. However, the
heavy processing demands of the task in which the label was presented complicated the
interpretation of the results; labels did not facilitate transfer, but it was unclear whether this
8
finding represented a true null finding, or whether the aforementioned complexity of the Keates
et al. (in revision) task, in conjunction with the challenge posed by the inherently dual nature of
pictures (DeLoache et al., 1996; Troseth, Pierroutsakos, & DeLoache, 2004), interfered with
infants’ capacity to process the naming information. As a result, the effect of naming on infants’
transfer of knowledge from picture books to the real world remains largely unknown.
The present study
To summarize, by 15-months of age, infants will learn a word for a depicted object and
will extend that word to the object’s real-world referent (e.g., Ganea et al., 2008, 2009).
Furthermore, infants 13- to 18-months of age possess the emergent ability to learn about objects’
nonobvious properties from picture book interactions and transfer this learning to real-world
objects (Keates et al., in revision). In addition, there is evidence that label information will help
slightly more proficient pictorial symbol users (i.e., children in their third year) use pictures
symbolically; however, it is unclear whether providing an object label to younger children will
result in the same facilitative effects.
The goal of the present study was to examine whether providing a label for a depicted
object facilitates infants’ transfer of information about that object’s properties from picture books
to the real world. Specifically, the present study investigated whether teaching 18- and 21-
month-old infants labels for objects depicted in picture books prior to teaching them about the
objects’ properties would help them generalize this information to the objects’ real-world
referents. To address this question, infants were assigned to either a label condition or a no label
condition. Using the picture book procedure of Ganea and colleagues (2008, 2009), infants in the
label condition were taught a novel label (e.g., “blicket”) for a depicted novel target object. The
picture book also contained pictures of an unlabeled, novel non-target object. Infants in the no
9
label condition received equal exposure to the picture book, but were not provided with a label
for the target. Following the initial picture book interaction, infants’ label-learning was assessed
by presenting them with a picture of the target and non-target objects asking them to indicate the
target. Infants in the no label condition were simply asked to choose one of the two pictures.
Infants in both conditions were then shown another picture book, which depicted an adult
interacting with the two objects. The depicted target object had a hidden, or nonobvious,
property (e.g., the toy lights up) that the depicted adult elicited by performing a target action
(e.g., pushing on the top of the toy). In the label condition, the newly learned label was used to
describe the target as the adult interacted with it. In the no label condition, the narration simply
described the adult interacting with the target without the use of a label. In both conditions, the
depicted non-target object did not have a nonobvious property, and accordingly, the narration
described the adult exploring the object without performing an action.
Following the second picture book interaction, infants in both conditions were tested
using the imitation procedure employed by Keates et al. (in revision), which is based on infants’
tendency to imitate a target action when they view a test object as belonging to the same
category as a target object (e.g., Baldwin, Markman, & Merlartin, 1993). Using this procedure,
infants were presented with two real test objects identical those depicted in the picture book (i.e.,
target and non-target). As a further test of infants’ learning, infants were subsequently presented
with a different colour exemplar (henceforth referred to as the “generalization exemplars”) of the
depicted target and non-target objects.
If object labels enhance infants’ understanding of the symbolic relationship between the
depicted target object and the real target object, then infants in the label condition should be
more likely to imitate the depicted action used to elicit the object’s nonobvious property (e.g.,
10
pushing on the toy) than infants in the no label condition. Further, if learning is more robust for
infants in the label condition, then they should be more likely than infants in the no label
condition to generalize their knowledge about the object’s nonobvious property to another
exemplar, as demonstrated by their performance of target actions on the generalization target
exemplar.
Two age groups were tested in order to capture potential age-related changes in infants’
ability to benefit from the naming information. The 18-month-old age group was tested in order
to allow for direct comparison with the oldest age group in the Keates et al. (in revision) study. It
was reasoned that if labels had a facilitative effect on infants’ transfer from pictures, this effect
would be more salient at 18-months of age than at either 15- or 13-months. The 21-month-old
age group was chosen for two reasons. First, the three-month age difference between the 18- and
21-month-olds was consistent with the difference between the age groups in the Keates et al. (in
revision) study (i.e., 13-, 15-, and 18-month-olds). Second a number of studies have investigated
24-month-olds’ transfer from picture books and found it to be relatively robust (e.g., Ganea et al.,
2009; Simcock & DeLoache, 2006, 2008). In order to observe any potential facilitative effects of
naming, it was necessary for infants to have some ability to transfer from picture books, but it
was also important for this task to be somewhat challenging for the infants. Accordingly, 21-
month-olds were reasoned to be a more logical age group than 24-month-olds.
Specific predictions for infants’ performance varied according to condition (i.e., label vs.
no label), infants’ age (i.e., 18- vs. 21-month-olds), and test trial (i.e., extension vs.
generalization trial). For the extension trial, it was predicted that approximately half the infants
in the no label condition, for both age groups, should learn and transfer the nonobvious property
information from the picture book to the real world. Across both age groups, a greater proportion
11
of the infants in the label condition were expected to perform target actions compared to infants
in the no label condition. Following from the Keates et al. (in revision) finding that there was no
effect of test trial on infants’ performance of target actions, it was predicted that about half the
infants in the no label condition would perform target actions on the generalization trial. This
pattern of performance was expected for both 18- and 21-month-old infants. Conversely, the
performance of infants in the label condition was expected to vary by age group. Specifically, it
was expected that more 21-month-olds, but not 18-month-olds, in the label condition would
perform target actions on the generalization target exemplar compared to their peers in the no
label condition. Thus, it was predicted that 21-month-olds would use the naming information to
help them overcome the perceptual dissimilarity between the depicted object and the
generalization target exemplar, but that this dissimilarity would disrupt 18-month-olds’ ability to
use the naming information. Finally, it was predicted that infants’ productive vocabulary and
experience with picture books would be related to the whether they performed target actions.
Specifically, it was predicted that infants whose parents read more picture books to them on a
daily basis, and who possessed larger productive vocabularies, would be more likely to perform
target actions.
Method
Participants
Participants were 87 infants from two age groups: 43 18-month-olds and 44 21-month-
olds. The infants in each age group were assigned to one of two conditions: the label condition (n
= 41) or the no label condition (n = 46). Infants’ mean age, mean productive vocabulary size, the
mean number of picture books parents reported reading with their infants per day, and gender
distribution, as a function of age group and condition, are presented in Table E1 (Appendix E).
12
For the 18-month-olds, infants in the no label condition (M = 141.63, SD = 131.64) produced
significantly more words than infants in the label condition (M = 64.21, SD = 55.88), t (41) = -
2.39, p < .021. For the 21-month-olds, infants in the label condition (M = 224.14, SD = 124.93)
produced significantly more words than infants in the no label condition (M = 134.59, SD =
95.26), t (42) = 2.67, p = .011. Maternal education and paternal education, as a function of age
and condition, can be found in Table E2 (Appendix E). An additional 29 infants were tested, but
were excluded from the final sample due to excessive fussiness (n = 21), parental interference (n
= 1), or for label condition, failure to learn any of the labels (n = 5). Participants were recruited
at local trade shows and through community advertisement (e.g., local newspapers, health
clinics). All infants were born full term and came from homes in which English was the primary
language spoken.
Materials
Object sets. Two object sets were used throughout the study: a light object set and a box
object set (see Appendix A). Each set consisted of four objects: a target object, a non-target
object, a different colour target exemplar, and a different colour non-target exemplar. For each
set, the generalization target or non-target exemplars (i.e., the different colour target or non-
target exemplars) were similar in shape, texture, and size to the target (or non-target) object, but
differed in colour. Photographs of the target and non-target from both sets objects were used
during the labelling phase, the label comprehension phase, and the nonobvious property phase
(see Appendix B, Figure B1 for photographs used during the labelling and label comprehension
phases; see Appendix B, Figure B2 for photographs used during the nonobvious property phase).
The actual, 3D objects were used during the test phase.
13
The target box object was a square-shaped box (13 cm in width x 13 cm in length x 13
cm in height) covered with fuzzy, blue polar fleece and topped with two long pieces of the same
material, crossed over one another. The box was filled with colourful ribbon, which was attached
to a spring glued to the bottom of the box. When the lid of the box was lifted, the ribbon inside
the box “popped up.” The generalization target exemplar was constructed identically to the target
object, but was covered with black, rather than blue, fuzzy polar fleece. The non-target object
was a rubber ball (3.34 cm in diameter) covered with orange corduroy and shaped with string
and sponge. The generalization non-target exemplar was identical to the non-target object, but it
was covered with grey, rather than orange, corduroy.
The target light object was a push light (21 cm in width x 21 cm in length x 2.5 cm in
height) covered with yellow felt. The different generalization target exemplar was a push light
covered with pink felt. The light inside the felt lit up when pressure was applied to the top of the
object. The non-target object was a triangular prism (10 cm in width x 12 cm in length x 9 cm in
height) covered with purple foam. The generalization non-target exemplar was identical to the
non-target object, but it was covered with green, rather than purple, foam.
Labelling phase. Stimuli consisted of two picture books (25 cm x 30 cm), each
containing 14 colour photographs (19 cm x 13 cm): six photos of familiar objects, four photos of
a novel target object, and four photos of a novel non-target object. Colour photos were chosen in
order to maximize the likelihood that infants would be able to transfer from the depictions;
previous research has established that infants under 24-months of age have difficulty using less
iconic images (e.g., colour line drawings) symbolically (e.g., Simcock & DeLoache, 2006). The
photos were presented on laminated pages (22 cm x 29 cm). Each photo depicted a solitary
object on a black background. Each picture book contained pictures of the target and non-target
14
objects from the two object sets described above. The same six familiar objects were used for
both picture books (shoe, ball, cup, apple, bottle, car). Familiar objects had labels produced by at
least 90% of 18-month-old infants, as indicated by the MacArthur-Bates Lexical Developmental
Norms (Dale & Fenson, 1996).
Typed narration was provided below each picture (see Appendix C for dialogue). In the
label condition, the narration referred to the target object using a novel label. In the no label
condition, the narration referred to the target object without using a label. When the book was
open, infants saw two pictures side-by-side (see Appendix B, Figure B1). Throughout the book,
pictures of familiar and novel objects were presented on opposite pages, with the exception of
the final two pages, where the novel target and familiar non-target were presented together.
Label comprehension phase. Stimuli consisted of eight individual, laminated pages (22
cm x 29 cm). Each page featured one photo of a solitary object. Photographs were identical to
those used in the label picture books (bottle, car, ball, cup, light object target, light object non-
target, box object target, box object non-target).
Nonobvious property phase. Stimuli consisted of two picture books with dimensions
identical to those of the labelling phase picture books. Each picture book contained 12 colour
photographs of an adult seated at a table with a novel object. In six photos, the adult was
depicted with a novel target object and in six photos the adult was depicted with the novel non-
target object. For the target, the adult performed an action that elicited the object’s nonobvious
property, and for the non-target, the adult explored the object without performing an action on it
(see Appendix B, Figure B2 and B3). Each photo was presented individually, such that when the
book was open, the picture was on the right side of the book.
15
Typed narration was provided below each picture. For the target object, the narration
described the adult eliciting the nonobvious property by performing the target action. In the label
condition, the narration described the adult eliciting the nonobvious property using the object’s
label (i.e., the label that was taught during the word learning phase). In the no label condition, the
narration described the adult eliciting the nonobvious property without using a label to refer to
the target object. In both conditions, the narration for the non-target object described the adult
exploring the object without performing an action. The narration was approximately equivalent
in length for the target and non-target picture sequences in order to equate the attention paid to
both depicted objects (see Appendix C for dialogue).
Test phase. Stimuli consisted of eight objects, four from each of the two object sets
described above (i.e., the box set and the light set). The target and non-target objects were used
for the extension trials and the generalization target and non-target exemplars were used for the
generalization trials (see Appendix A for pictures of the object sets). A handheld stopwatch was
used to time the trials.
Procedure
The infant was seated across a table from the experimenter, either in a booster chair or on
the parent’s lap. The parent was instructed not to direct, prompt, or cue the infant during the task.
The parent was further instructed to place objects back within reach of the infant if the infant
handed the objects to them or dropped the objects on the floor. Testing consisted of two blocks
of four phases: labelling phase, label comprehension phase, nonobvious property phase, and test
phase. Each block corresponded with one object set (i.e., the box set or the light set). For coding
purposes, all sessions were recorded using a 6.1 MP Sony Digital HD video camera.
16
Labelling phase. To begin the labelling phase, the experimenter told the infant that she
was going to read him or her a book. The experimenter then sat down next to the child at a table,
and opened the book to the first page. The experimenter proceeded to read the narration on each
page, while pointing to the depicted object. For each familiar picture, the experimenter labelled
the depicted object once (e.g., “Look, it’s a car.”). For the novel target object, the experimenter
labelled the depicted object three times (e.g., “Look, this is a blicket. Wow, it’s a blicket. See a
blicket?”). For the non-target object, and the target object in the no label condition, the
experimenter drew the infant’s attention to the depicted object three times without labelling it
(e.g., “Look, look at that. Wow, it’s that. See that?”). For each page, the experimenter monitored
the infant’s eye gaze to ensure the infant looks at the depicted object. If the infant was not
attending to one of the pages, the experimenter paused and redirected the infant’s attention
(“Look!”). When the infant was once again attending to the picture book, the experimenter
continued with the narration.
For each pair of pictures (i.e., a familiar object and novel object), the familiar object was
presented first, on the left side of the book, and the novel object was presented second, on the
right side of the book. The order in which the novel target and non-target objects were presented
in the picture book was counterbalanced across infants. That is, for half the infants, a familiar
object/novel target object picture pair was presented first, followed by a familiar object/novel
non-target picture pair. The other half of the infants saw the opposite order of picture pairs
(familiar/novel non-target followed by familiar/novel target).
Label comprehension phase. Following the picture book-reading interaction, the
experimenter repositioned herself so that she was sitting across the table from the infant. Label-
learning was assessed for infants in the label condition. First, the experimenter presented two
17
pictures of familiar objects and asked the infant to indicate one of them (“Show me the car [ball,
shoe, bottle].”). The object requested, as well as the side on which the target picture presented,
was counterbalanced across participants. If the infant did not respond, the experimenter used
alternate phrases (e.g., “Where’s the car?” or “Point to the car.”), until a response was elicited. If
the infant did not respond to the experimenter, the experimenter instructed the parent to repeat
the phrases, until a response was elicited. On subsequent trials, the experimenter asked the child
to indicate the objects using whichever phrase had elicited a response. Second, to assess whether
infants had learned the novel label for the depicted target object, the experimenter presented two
photographs: one of the novel target and one of the novel non-target. She then asked the infant to
indicate the target (“Show me the blicket.”). Infants were given positive reinforcement (e.g.,
“That’s right! Good job!”) when they chose the target picture and were given corrective feedback
(e.g., “Remember, this one is the blicket.”) when they chose the non-target. The criterion was
two correct successive responses on two trials, with a maximum of four possible trials, following
that used in previous research (e.g., Ganea et al., 2009).
Infants in the no label condition were also shown the pair of familiar objects and the pair
of novel objects (i.e., target and non-target). Rather than being asked to indicate a specific object,
infants were asked to show either one of the objects to the experimenter (“Show me one.”). The
experimenter prompted the infant (as described above), until the infant chose one of the objects.
Regardless of the infant’s choice, the experimenter provided a neutral response (“Thank you.”).
Nonobvious property phase. After the label comprehension phase, the experimenter
introduced the nonobvious property book by explaining that the girl in the book had found some
toys and that they were going to look at the toys together. Then, the experimenter read the book
to the infant in the manner described in the labelling phase section. The infant saw a sequence of
18
six photographs of the adult interacting with the first novel object (e.g., the target), followed by a
sequence of six photographs of the adult interacting with the second novel object (e.g., the non-
target). For half the infants, the target object sequence was presented first, and for the other half,
the non-target object was presented first. The order of presentation of the pictures within each
sequence was fixed (see Appendix D for the sequence of photos from the box set picture book).
Test phase. Immediately after the experimenter finished reading the nonobvious property
book, she repositioned herself so that she was sitting across the table from the infant. The infant
was then given the extension test trial. The experimenter simultaneously placed the exact target
and non-target objects that were depicted in the book on the table, out of reach of the infant. She
then encouraged the infant to explore the objects and pushed them toward the infant until they
are within his or her reach. The experimenter introduced the objects to infants in the label
condition using the newly learned label (e.g., “Look. There’s a blicket here. Now you get to
play!”). The experimenter introduced the objects to infants in the no label condition by
substituting the word “toy” for the object label (e.g., “Look. There’s a toy here. Now you get to
play!”). The infant then had the opportunity to explore the objects for 20 seconds. After 20
seconds had elapsed, the experimenter retrieved the two objects and intitiated the generalization
test trial. The experimenter simultaneously placed the generalization target and non-target
exemplars on the table, out of reach of the infant. She introduced the objects using the same
newly learned label (e.g., “Look. There’s a blicket here. Your turn again!”) for infants in the
label condition, or substitued the word “toy” for infants in the no label condition. She then placed
the objects within the infant’s reach. The infant were again given 20 seconds to explore the two
objects. If, over the course of the 20 second exploration period, the infant could no longer reach
19
the object (e.g., because it fell off the table), the experimenter or parent re-placed the object in
front of the infant within his or her reach.
Once the first block was completed, the second block was administered as described
above. The order of the blocks was counterbalanced across infants. That is, half the infants were
presented with the box object set followed by the light object set, and half the infants were
presented with the light object set followed by the box object set.
Following the testing session, the parent was asked to participate in a short, informal
interview, and to complete the MacArthur-Bates Communicative Development Inventory: Words
and Sentences (CDI; Fenson et al., 2007), a measure of productive vocabulary. The interview
consisted of a standard set of open-ended questions, which focused on the number of picture
books the infant and parent read together per day, and the nature of the picture book interactions
(see Appendix D for specific items). The infant received a t-shirt, a toy, and a “Child Scientist”
certificate for his or her participation.
Coding and Reliability
Infants’ attempts to elicit target objects’ nonobvious properties were coded offline by
trained coders, unaware of the experimental hypotheses, using Final Cut Pro 7 software. The
target action for the box object set was defined as forcefully pulling upward on the material on
top of the object. Picking at or touching the material on the top of the object without lifting or
pulling the material, lifting the long pieces of material on the top of the object without using
force (e.g., lightly holding them a vertical position), or shaking or squeezing the object, were not
coded as target actions. The target action for the light object set were defined as hitting, pushing
on, or tapping the object with the hand or fingers using a swift “tap-like” motion. Actions
performed on the excess felt around the push light, rather than on the top or side of the felt-
20
covered push light itself, were not coded as target actions. Lightly resting a hand on top of the
object, without pushing or applying pressure, or touching the object in order to feel or poke it,
were also not coded as target actions. For both object sets, actions performed in order to pick up,
throw, move the object closer to oneself, or pass the object to either the parent or the
experimenter, were not coded as target actions. Eighteen-month-old infants in the baseline
condition of Keates et al. (in revision) were not found to spontaneously perform target actions on
the target objects.
Coders also recorded the amount of time infants spent examining the target or non-target
objects. Examination time was used as a measure of infants’ interest in the objects, and was
defined as the number of seconds spent looking at or looking at and touching the objects.
An additional coder, unaware of the experimental hypotheses, coded 20% of the videos.
Inter-rater reliability for target actions on target objects was high (κ =. 968). Inter-rater reliability
for examination time coding was also high (intraclass correlation coefficient = .980).
Results
Prior to conducting the analyses, comprehension of the object labels was assessed for
infants in the label condition. Infants who had not learned at least one of the object labels were
excluded from subsequent analyses (n = 5). It was important to ensure that infants were in fact
associating the novel label with the novel target objects so that any observed differences in the
performance of the label and no label condition could be attributed to differences in access to
naming information. Next, infants’ learning and transfer of nonobvious properties was analyzed
in two ways. First, infants’ performance of the depicted target action on the real target object was
analyzed to determine whether they had successfully transferred their learning from the depicted
target to its real-world referent. Specifically, if infants expected the real-world target and
21
depicted target objects to share a nonobvious property, then they should attempt to elicit this
property by performing a target action on the real, 3D target object. Second, the time that infants
spend examining the target objects relative to the non-target objects was analyzed as a measure
of infants’ interest in the target objects during the test trials. Interest in the target objects was
assessed because, given the complex nature of the task and its associated cognitive demands, it
was possible that infants had learned and remembered that the target object had a nonobvious
property, but lacked a recollection of the target action necessary to elicit this property. If this
were the case, then infants should have had longer examination times for the target object than
for the non-target object.
Object labels
Infants in the label condition all learned at least one novel label for one target object, as
indicated by the criterion of two correct successive responses on two trials during the label
comprehension phase for that object. Overall, 21 infants demonstrated evidence of learning the
novel labels for both target objects (i.e., learned the label for both the light and box target object)
and 20 learned the label for one of the two target objects (i.e., learned the label for either the light
or the box target object). Fewer 18-month-olds than 21-month-olds learned both labels with 37%
of 18-month-olds learning two labels compared to 64% of 21-month-olds, however this
difference was not statistically significant, χ2 (1, N = 41) = 2.93, p = .087.
Nonobvious properties
Target actions. Sequential logistic regression analyses were conducted to assess the
prediction of test outcome (learning vs. no learning from picture books). Test outcome (i.e.,
whether or not infants had learned about the depicted target objects’ nonobvious properties from
the picture book interaction) was determined by their attempts to elicit these properties by
22
performing target actions on the target objects. Recall that each infant was given two types of
test trials: an extension trial in which the test objects were identical to the depicted objects and a
generalization trial in which the test objects were different-coloured exemplars of the depicted
objects (i.e., generalization exemplars). Infants were given an extension test trial and a
generalization test trial for both object sets (i.e., box and light object set), yielding up to 4 trials
total. There was no significant difference between infants’ performance of target actions on the
light target and infants’ performance of target actions on the box object (McNemar test, p =
.164).
The primary dependent variable was whether or not the infant demonstrated evidence of
transferring information from the depicted object to its real-world referent, and whether the
infant demonstrated evidence of generalizing this information to a novel exemplar. Thus, rather
than receiving a score of 0, 1, or 2, infants were instead classified as having learned or not
learned from the picture books on the extension trial, and as having generalized or not
generalized from the picture books for the generalization trial. Accordingly, infants were given
credit for performing a target action on either the light or the box object target object for the
extension trial, and were given credit for performing a target action on either the light or the box
generalization target exemplar for the generalization trial. If infants performed target actions on
both sets, no additional credit was given.
Table 1 displays the test outcome by condition and age group contingency table for the
extension trial. Table 2 displays the test outcome by condition and age group contingency table
for the generalization trial. Values for 8 cases with missing productive vocabulary scores were
imputed using the EM algorithm included in the MVA package of IBM’s SPSS Statistics
23
(version 20). The pattern of missing data was not found to deviate significantly from randomness
using Little’s MCAR test, p = .566.
Table 1. Extension trial: Learning as a function of condition and age group.
Attempt to elicit property
Age group Condition No Yes Total
18-month-olds
No Label 14 10 24
Label 9 10 19
Total 23 20
21-month-olds
No Label 10 12 22
Label 4 18 22
Total 14 30
Table 2. Generalization trial: Learning as a function of condition and age group.
Attempt to elicit property
Age group Condition No Yes Total
18-month-olds
No Label 12 12 24
Label 9 10 19
Total 21 22
21-month-olds
No Label 10 12 22
Label 4 18 22
Total 14 30
24
Preliminary analyses indicated that the following variables did not meaningfully
contribute to the prediction of test outcome: the order in which object sets were presented (i.e.,
light object set first vs. box object set first), the number of blocks infants completed (one vs. two
blocks), and maternal or paternal education. That is, these variables did not contribute
significantly to the models for either the extension trials, χ2 (7, N = 82) = 9.18, p = .240 or
generalization trials, χ2 (7, N = 82) = 4.48, p = .724. Examination of the Wald statistic for each
individual predictor provided further confirmation that the inclusion of these variables did not
significantly enhance prediction, ps > .145 for extension trials, ps > .319 for generalization trials.
Accordingly, these variables were excluded from subsequent analyses.
In order to explore the contribution of naming to infants’ performance on the extension
test trial, a sequential dichotomous logistic regression was conducted, with attempt to elicit a
target object’s nonobvious property for at least one target object set (performance of a target
action vs. no performance of a target action) as the dependent variable (see Appendix E, Table
E3). Gender, productive vocabulary (as indicated by parental report on the MCDI), and the
number of picture books parents reported reading with their infant daily, were entered on step 1.
Age group (18-month-olds vs. 21-month-olds) was entered on step 2. Condition (label condition
vs. no label condition), was entered on step 3.
For step 1, the Likelihood Ratio test for the overall model was not significant, χ2 (3, N =
87) = 4.55, p = .208, indicating that compared to a constant-only model, the demographic
predictors as a set did not contribute to the prediction of infants’ performance of target actions.
Examination of the Wald statistic for the individual predictors confirmed that neither variable
contributed significantly to prediction (ps > .140). The addition of age group to the model in
step 2 improved the model fit to some extent, however this improvement was not statistically
25
significant, χ2 (1, N = 87) = 2.87, p = .090, and the overall model remained non-significant χ2 (4,
N = 87) = 7.42, p = .115. When condition was added to the model in step 3, there was a
marginally significant improvement in fit, χ2 (1, N = 87) = 3.78, p = .052, which improved
prediction enough for the Likelihood Ratio test for the overall model to become significant, χ2 (5,
N = 87) = 11.19, p = .048. Despite the statistical significance of the model with all five predictors
compared to the constant-only model, the effect size was small, Nagelkerke = .162, indicating
that these variables accounted for only 16.2% of the between-group variance.
Table E4 (Appendix E) shows regression coefficients, Wald statistics, odds ratios, and
95% confidence intervals for the odds ratios for each individual predictor. The only predictor
that contributed to the prediction of whether an infant would attempt to elicit a nonobvious
property by performing a target action was condition, which was marginally significant, B = .90,
SE = .47, Wald(1) = 3.65, p = .056. For infants in the label condition, the odds in favour of
performing a target action on a target object were 2.45 times larger than for infants in the no
label condition; 68% (28/41) of infants in the label condition performed target action compared
to 48% (22/46) of infants in the no label condition. Examination of the condition by age group
contingency table (Table 1) revealed a different pattern of performance based on age group.
Specifically, the difference between the label condition and the no label condition appeared to be
driven by the 21-month-olds. At 18-months, 42% of infants in the no label condition compared
to 53% in the label condition performed target actions, suggesting that the label had at worst no
effect and at best a negligible effect on infants’ transfer from picture books. At 21-months,
however 55% of infants in the no label condition performed target actions compared to 82% of
infants in the label condition. These results suggest that there may be developmental differences
in infants’ use of naming information.
26
To explore the contribution of naming to infants’ performance on the generalization test
trial, a second sequential dichotomous logistic regression was performed (see Appendix E,
Table E5). The dependent variable and predictors, as well as the steps of the analysis, were
identical to those described for the extension test trial. For step 1, the Likelihood Ratio test for
the overall model was not significant, χ2 (3, N = 87) = 7.00, p = .072. Examination of the Wald
statistic for the individual predictors revealed that productive vocabulary (p = .045), but not
gender or the number of picture books read daily with a parent (ps > .139), significantly
contributed to the prediction of performance of target actions. However this finding should be
interpreted with caution given that the overall model was not significant. The addition of age
group in step 2 did not significantly improve the fit of the model χ2 (1, N = 87) = 1.03, p = .311
and the fit of the model did not become significant χ2 (4, N = 87) = 8.03, p = .091. The addition
of condition to the model in step 3 also did not significantly improve the fit of the model, χ2 (1, N
= 87) = 2.38, p = .123. A test of the model with all five predictors against a constant-only model
remained non-significant χ2 (5, N = 87) = 10.41, p = .065, indicating that the variables, as a set,
did not reliably distinguish between infants who had and had not performed target actions. The
effect size for the model was small, Nagelkerke = .152, indicating that the full model accounted
for only 15.2% of the between-group variance.
With regard to individual predictors (see Appendix E, Table E6), the significance of the
Wald statistic for productive vocabulary at step 1 suggested that this predictor might contribute
significantly to the fit of the model. However, with all of predictors in the model, the unique
variance predicted by productive vocabulary was no longer significant, B = .004, SE = .002,
Wald(1) = 2.79, p = .095. The Wald statistic has been shown to “behave in an aberrant manner”
(Pedhauzer, 1997), and it has been suggested that it should not be solely relied upon for the
27
interpretation of effects of individual predictors. Thus, to test the contribution of productive
vocabulary, it was removed from the full model (i.e., the model with all five predictors).
Removal of productive vocabulary from the full model did not significantly increase the amount
of unexplained variance, χ2 (1, N = 87) = 2.98, p = .084, suggesting that, consistent with the
Wald statistic, productive vocabulary did not contribute significantly to the overall model fit.
Thus, unlike the extension test trial, in which condition was a significant predictor of infants’
performance, for the generalization test trial none of the predictors reliably distinguished
between infants who learned and did not learn from the picture book.
Examination time. In an additional set of analyses, the time that infants spent examining
the target objects over the course of the test trials was analyzed. Recall that examination time
was defined as the number of seconds that infants spent looking at or looking at and touching the
target or non-target objects. Examination time for target objects was proportionalized by dividing
the number of seconds infants spend interacting with the target object by their total examination
time for both the target object and non-target object. The proportion of examination time for each
object set (i.e., the light object set and box object set) was averaged to yield one mean target
object examination time score for each trial type (i.e., extension and generalization).
It was hypothesized that for both the extension and generalization trials, infants in the
label condition would have longer examination times (i.e., would spend a greater proportion of
the test trials examining the target object) than infants in the no label condition. This pattern of
examination times would indicate that infants who heard the same label used to describe the
target depicted in the picture book and the real-world target object had a greater appreciation of
the link between the depicted and real-world target objects. Although a similar pattern of interest
in the target objects was expected across age group and trial type, the examination times for the
28
younger age group were of particular interest. Specifically, it was hypothesized that age-related
changes in memory capacity might mean that fewer infants in the 18-month-old group would
perform target actions, but that 18-month-olds in the label condition would spend more time
inspecting and interacting with the target objects than infants in the no label condition.
Table 3. Extension and generalization trials: Mean proportion examination times for the target
object by condition and age group.
a Averaged across age groups
To examine whether infants’ examination times for the target objects varied as a function
of condition, age group, and test trial, a 2 (Condition: Label vs. No Label) x 2 (Age Group: 18-
month-olds vs. 21-month-olds) x 2 (Test Trial: Extension vs. Generalization) mixed factor
ANOVA was conducted with test trial as a repeated measure. Examination times for each
condition and age group, separated by trial type, are presented in Table 3. This analysis revealed
a significant main effect of age group, F (1, 83) = 4.80, ηp2 = .06, p < .05, with 21-month-old
infants spending significantly more time examining the target objects on the test trials than 18-
Test trial
Extension Generalization
Condition Age Group M (SD) M (SD)
No Label
18 Months .45 (.24) .56 (.22)
21 Months .54 (.19) .59 (.18)
Mean a .49 (.22) .57 (.20)
Label
18 Months .45 (.16) .52 (.19)
21 Months .57 (.16) .60 (.18)
Mean a .52 (.17) .56 (.19)
29
month-old infants. There was also a significant main effect of test trial, F (1, 83) = 7.71, ηp2 =
.09, p < .05, with infants spending significantly more time examining the target objects on the
generalization test trials than on the extension test trials. There was no effect of condition and no
significant two-way or three-way interactions involving age group, test trial, or condition, ps >
.252. Contrary to our hypotheses, infants in both the label and the no label conditions were
equally interested in the target objects, suggesting that labelling did not increase infants` interest
in the targets. As a group, the 21-month-olds were significantly more interested in the target
objects than the 18-month-olds, and across age groups, infants were more interested in the
generalization target exemplars than the exact target objects depicted in the picture books.
Discussion
The present study investigated whether naming would facilitate infants’ transfer of
information from picture books to the real world. When infants were presented with the exact
object depicted in the picture book (the extension trial), more than half the infants transferred the
object’s nonobvious property from the depicted to the real-world target object. This finding
replicates the study of Keates et al. (in revision), in which infants aged 13- to 18-months of age
transferred nonobvious properties from picture books to the real world. The present results are
also consistent with previous research demonstrating that infants in their second year of life
possess a developing ability to take information from picture books and apply it to real objects
(e.g., Ganea et al., 2008; Preissler & Carey, 2004; Simcock & DeLoache, 2006). Further, the fact
that 18- and 21-month-old infants successfully transferred information about object properties
from depicted to real-world objects, supports a growing body of evidence that infants possess a
nascent understanding of the symbolic nature of pictures (Ganea et al., 2008; 2009; Preissler &
Carey, 2004; Simcock & DeLoache, 2006; Simcock & Dooley, 2007; Simcock et al., 2011).
30
For the extension trial, whether or not infants had been provided with a novel label for
the target object was an important predictor of performance of target actions (although not yet
reaching statistical significance). Specifically, for infants in the label condition, the odds of
attempting to elicit a target object’s nonobvious property were almost 2.5 times greater than for
infants in the no label condition. This is consistent with other research that has shown that
language in the form of object labels and other narrative cues improves imitation from not only
picture books, but also television, another 2D symbolic medium (e.g., Barr, 2010; Barr & Wyss,
2008; Seeghagen & Herbert, 2010; Simcock et al., 2011). Why might this be the case? It has
been proposed that labelling a depicted object highlights its symbolic status (e.g., Priessler &
Bloom, 2007), calling attention to relationship between the depicted object and its referent. It has
also been posited that labels may act as a memory cue that, when provided at encoding and
retrieval, lightens some of the processing demands associated with recall (Hayne & Herbert,
2004; Herbert & Hayne, 2000). In addition, it has been theorized that naming increases the
salience of the similarity between objects (Waxman, 2008). Finally, infants have been shown to
use shared labels to establish whether objects belong to the same category and accordingly, to
determine whether objects share nonobvious properties (e.g., Graham et al., 2004; Keates &
Graham, 2008). In the present study, labels may have reduced the perceptual processing and
memory demands associated with transferring information from a 2D picture to a 3D object, as
well as highlighting the symbolic relation between the object depicted in the picture book and the
real-world test object.
Although relative to the other predictors, the condition to which an infant had been
assigned (label or no label) was the most important predictor of his or her performance on the
extension test trial, the effect of the label was in fact rather small and only marginally
31
statistically significant. Consideration of the pattern of results by age group raises the possibility
that the effect of the label was diluted as a result of including both the 21-month-olds and the 18-
month-olds in the same analysis. Specifically, there was very little difference in performance of
target actions between label and no label conditions within 18-month-old group (53% vs. 42%
performed target actions). In contrast, 82% of the 21-month-old infants in the label condition
performed target actions compared to only 55% of infants in the no label condition. This pattern
of results suggests developmental differences in the ability to make use of label information.
The argument that there were age-related changes in infants’ performance may appear
contrary to the finding that age was not a significant predictor in the logistic regression model.
However, the fact that age did not emerge as a significant predictor is likely due to the fact that it
was correlated with productive vocabulary, and as a result of having both in the model, the
unique contribution of each variable was reduced. Regardless of whether the differences between
the 18-month-old group and 21-month-old group were driven by age or productive vocabulary,
there were clear dissimilarities between the effects of naming for older infants with more
developed productive vocabularies compared to younger infants who produced fewer words.
These differences, as well as potential reasons why age-related changes in the ability to use
naming information were observed in this task, are explored below.
When infants were presented with the generalization target exemplar, more than half the
infants demonstrated evidence of learning and transferring the object’s nonobvious property
from the picture book. This suggests that infants were able to generalize their learning to an
instance of the target that was more perceptually dissimilar to the depiction than the test object in
the extension trial. The finding that infants will apply information about a depicted object to a
slightly different category member, after first seeing the exact object that had been depicted in
32
the book, is consistent with the findings of Keates et al. (in revision).
For the generalization trial, condition was no longer a significant predictor of infants’
transfer of nonobvious properties. This is surprising, given the fact that infants were expected to
rely more heavily on the label in the absence of strong perceptual similarity between the depicted
target and the generalization target exemplar. Contrary to the hypothesis that perceptual
dissimilarity would interfere with transfer, it appears as though infants were actually more
interested in the generalization target exemplar, as indicated by an increase in examination times
on this trial. It is possible that infants were more eager to explore the novel target and as a result,
the already small effect of the label became even less pronounced. Overall, none of the
predictors that had been related to performance for the extension trial was able to distinguish
between infants who performed target actions on the generalization trial.
Turning to the findings of the present study more globally, it becomes apparent that the
number of 18-month-old infants who attempted to elicit the target object’s nonobvious property
is almost identical to the number of infants who performed target actions in the Keates and a
colleagues (in revision) study. In both studies, only about half of the 18-month-olds performed
target actions on either the extension or the generalization trials. The performance of 21-month-
old infants in the no label condition for both the extension and generalization trials was quite
similar to the overall performance of 18-month-olds; only about half attempted to elicit the
object’s nonobvious property.
The methodology of the present study did not allow for conclusive statements about
whether these infants had neither learned nor transferred information from the picture books, or
whether they had learned the object’s nonobvious property but experienced difficulty
remembering or performing the appropriate target action. The relatively equal inspection of and
33
interaction with the target and non-target objects within this age range would suggest that infants
were no more interested in the target than the non-target, potentially signifying that they did not
expect the real 3D target to have a nonobvious property. Another way to address this question
would be to conduct a violation of expectation experiment, in which the experimenter performs
the target action on the target object, but fails to elicit the object’s nonobvious property (e.g., hits
the light but it does not light up).
The current study adds to the growing body of literature documenting the challenges
experienced by infants when faced with the task of transferring complex information from 2D to
3D contexts. Studies examining infants’ imitation of action sequences from pictures have
consistently found that 18-month-olds who are presented with a depicted, three-step action
sequence do not re-enact the entire sequence (Simcock & DeLoache, 2006; Simcock & Dooley,
2007), and further, have difficulty producing the target actions in the correct order (Simcock et
al., 2011). The current findings are also consistent with the video deficit effect, that is, the fact
that infants’ transfer of learning from television to the real world is poor relative to their transfer
of learning from live demonstrations and other face to face interactions (e.g., Barr & Hayne,
1999; Hayne, Herbert, & Simcock, 2003; Kuhl, Tsao, & Liu, 2003; Troseth & DeLoache, 1998).
A number of accounts have been put forth to explain infants’ difficulty transferring information
from 2D sources to 3D objects and situations (for a review, see Barr, 2010).
According to Hayne’s (2004) representational flexibility hypothesis, successful memory
performance depends on perceiving a match between cues at encoding and cues at retrieval. As
infants develop, the degree to which the encoding cues must match the retrieval cues becomes
more flexible. Thus, early in development it is challenging for infants to transfer learning from
2D, static pictures to 3D objects because there is a distinct mismatch between the cues at
34
encoding and retrieval. The perceptual impoverishment account emphasizes that the perceptual
input provided by 2D sources is impoverished relative to the 3D input provided by live
interactions, similarly resulting in impaired encoding and transfer (Barr, 2010; Barr & Hayne,
1999; Suddendorf, 2003; Suddendorf, Simcock, & Nilsen, 2007). Finally, DeLoache and
colleagues’ dual representation hypothesis (DeLoache, 1987, 1991; DeLoache et al., 1996)
predicts that infants would experience difficulty transferring from 2D to 3D because of the dual
nature of 2D symbols, which are both objects in and of themselves, as well as representations of
entities in the world. The challenges outlined by each of these theories likely contributed to the
tenuous transfer by 18-month-olds in both conditions and by 21-month-olds in the no label
condition.
It is also likely that the competing demands on cognitive resources associated with the
above processes interfered with 18-month-olds’ ability to use the naming information that was
provided. That is, as a consequence of their limited working memory capacity (Hauf, 2009),
infants may have been unable to keep the object label in mind when faced with additional
cognitive demands. For example, it is possible that infants learned the object label and even
associated the label with the object’s nonobvious property, but that they were then unable to keep
the label in mind during the cognitively demanding test trials. In order to succeed on the test
trials, infants had to hold the object’s physical appearance, its nonobvious property, and how to
elicit this property in mind, select the correct target object, and perform the appropriate target
action. When the cognitive complexity of the test trials is considered in addition to the
aforementioned cognitive demands associated with transferring from 2D to 3D, it seems rather
unlikely that infants’ limited working memory capacity would allow them to bring to mind and
manipulate the label and nonobvious property information simultaneously. Thus, they may not
35
have been able to use the information seemingly conveyed by object labels.
A recent study by Zack and colleagues (in press), examining 15-month-old infants’
imitation from touch screens, similarly failed to find facilitation from shared labels. As in the
present study, their task was relatively complex, required infants to transfer information from a
2D symbolic medium to a 3D real-world object and found that the addition of object labels had
no effect on infants’ transfer. In addition to the present study and the Zack et al. (in press) study,
Keates (2010) also found that labelling objects during a picture book interaction did not improve
18-month-olds’ transfer of information from picture books. Thus, it appears that the lack of
facilitation reported here, though inconsistent with studies documenting the facilitative effects of
naming in other types of tasks (e.g., Booth & Waxman, 2002; 2003; Graham et al., 2004; Keates
& Graham, 2008; Waxman, 2008; Herbert, 2011), is in fact quite consistent with the findings of
studies whose methodology more closely parallels that of the present study. A tentative
conclusion that can be drawn from these findings is that prior to 21-months of age, naming does
not enhance infants’ transfer from 2D images to 3D objects.
What might account for the observed age differences in ability to make use of label
information? First, 21-month-olds possess more advanced representational systems than 18-
month-olds, including language and memory systems, as well as more developed perceptual and
motor systems (Barr, 2010). Second, 21-month-olds have had more time to become familiar with
symbols, and to have experiences that clarify the symbolic relations between symbols and their
referents. Accordingly, they may have a more robust understanding of the symbolic nature of
pictures. Finally, 21-month-olds’ overall cognitive processing is likely faster, and more flexible
than that of younger infants, allowing them to integrate perceptual and linguistic input more
quickly (see Barr, 2010).
36
The present findings have practical implications for parents and educators who wish to
use picture books to teach infants about the world. Specifically, the results of the current study
suggest that the ability to learn complex information from picture books may be rather limited in
infants younger than 21 months. That is not to say that joint picture book reading is without
merit; these interactions have a number of other documented benefits, including helping infants
to learn the sounds of their native language (Foy & Mann, 2003) and enhancing vocabulary
development (DeBaryshe, 1993; Senechal & Cornell, 1993). Previous research would suggest
that engaging in the “point and label” games that often characterize shared picture book reading
may in fact help to teach young infants new words for real objects (e.g., Ganea et al., 2008, 2009;
Preissler & Carey, 2004). Conversely, the results of the current study suggest that for infants
younger than 21 months, information about objects’ properties or unfamiliar actions may not
transfer beyond the pages of the book.
Future research could examine whether there are ways to enhance younger infants’
transfer of complex information. For example, it is possible that in the present study, the novelty
of the label, the object, and the label-object pairing may have negatively impacted 18-month-
olds’ ability to use the label to guide their transfer of information. Future research could examine
whether increasing the familiarity of the target object and label, and strengthening the association
between them by providing multiple exposures to the object-label pairing over the course of a
week, would result in facilitated transfer of the object’s nonobvious property at test. It is also
possible that labels simply do not enhance transfer from 2D representations to 3D objects prior to
21-months of age. If this were the case, it would be important to investigate whether other kinds
of information might facilitate slightly younger infants' learning and transfer. For example,
additional research could examine the effects of highlighting the symbolic relationship between
37
pictures and objects (e.g., Callaghan & Rankin, 2002), or the effects of presenting infants with
multiple different-coloured exemplars of the target object while teaching them about the objects’
nonobvious property.
A limitation of the present study was the fact that the extension trial always preceded the
generalization trial. Although consistent with the order of test trials in previous studies (e.g.,
Ganea et al., 2008; Keates et al., in revision), it leaves open the possibility that infants were not
performing target actions on the generalization target exemplar because they viewed it as
members of the same category as the depicted target object. Instead, infants may simply have
been transferring their knowledge about the object’s nonobvious property from the real object
presented during the extension trial to the real generalization exemplar. In order to address this
issue, future research should examine whether infants will generalize to a novel exemplar
directly from a picture book, without first seeing a target that is identical to the object depicted
on an extension trial.
In summary, the present study provides insight into the development of the ability to
transfer information from symbolic media to the real world. These results show that infants can
learn about objects’ properties from a brief picture book interaction and transfer this learning to
real-world objects. Further, the results of the present study extend previous research by
demonstrating that shared labels have the capacity to facilitate this transfer. Importantly, there
were age-related changes in the ability to apply naming information to the task of transferring
complex information. The existence of these developmental changes suggests that parents of
infants 21-months and older might be able to scaffold infants’ transfer from picture books by
providing shared labels for depicted and real-world objects, but that the same educational
strategy may not result in comparable facilitative effects for younger infants.
38
References
Baldwin, D. A., Markman, E. M., & Melartin, R. L. (1993). Infants’ ability to draw inferences
about nonobvious object properties: Evidence from exploratory play. Child Development,
64, 711-728.
Barr, R. (2010). Transfer of learning between 2D and 3D sources during infancy: Informing theory
and practice. Developmental Review, 30, 128-154.
Barr, R., & Hayne, H. (1999). Developmental changes in imitation from television during
infancy. Child Development, 70, 1067–1081.
Barr, R., & Wyss, N. (2008). Reenactment of televised content by 2-year-olds: Toddlers use
language learned from television to solve a difficult imitation problem. Infant Behavior
and Development, 31, 696-703.
Booth, A. E., & Waxman, S. R. (2002). Object names and object functions serve as cues to
categories for infants. Developmental Psychology, 38, 948-957.
Booth, A. E., & Waxman, S. R. (2003). Mapping words to the world in infancy: Infants’
expectations for count nouns and adjectives. Journal of Cognition and Development, 4,
357-381.
Callaghan, T. C. (1999). Early understanding and production of graphic symbols. Child
Development, 70, 1314-1324.
Callaghan, T. C. (2000). Factors affecting children’s graphic symbol use in the third year:
Language, similarity, and iconicity. Cognitive Development, 15, 185-214.
Callaghan, T. C., & Rankin, M. P. (2002). Emergence of graphic symbol functioning and the
question of domain specificity: A longitudinal training study. Child Development, 73, 359-
376.
39
Callaghan, T. C., Rochat, P., MacGillivray, T., & MacLellan, C. (2004). Modeling referential
actions in 6- to 18-month-old infants: A precursor to symbolic understanding. Child
Development, 75, 1733-1744.
DeBaryshe, B. D. (1993). Joint picture-book reading correlates of early oral language skill.
Journal of Child Language, 20, 455–461.
DeLoache, J. S. (1987). Rapid change in the symbolic functioning of very young children.
Science, 238, 1556-1557.
DeLoache, J. S. (1991). Symbolic functioning in very young children: Understanding pictures
and models. Child Development, 62, 736-752.
DeLoache, J. S. & Ganea, P. A. (2009). Symbol-based learning in infancy. In A. Needham & A.
Woodward (Eds.), Learning and the infant mind (pp. 263-285). Oxford: Oxford University
Press.
DeLoache, J. S., & Burns, N. M. (1994). Early understanding of the representational function of
pictures. Cognition, 52, 83-110.
DeLoache, J. S., Pierroutsakos, S. L., & Troseth, G. L. (1996). The three ‘R’s of pictorial
competence. In R. Vasta (Ed.), Annals of child development (Vol. 12, pp. 1-48). London:
Jessica Kingsley Publishers Ltd.
DeLoache, J. S., Pierroutsakos, S. L., & Uttal, D. H. (2003). The origins of pictorial competence.
Current Directions in Psychological Science, 12, 114-118.
DeLoache, J. S., Pierroutsakos, S. L., Uttal, D. H., Rosengren, K. S., & Gottlieb, A. (1998).
Grasping the nature of pictures. Psychological Science, 9, 205-210.
DeLoache, J. S., Strauss, M. S., & Maynard, J. (1979). Picture perception in infancy. Infant
Behaviour and Development, 2, 77-89.
40
Fenson, L., Marchman, V. A., Thal, D. J., Dale, P. S., Reznick, J. S., & Bates, E. (2007).
MacArthur-Bates Communicative Development Inventories. Baltimore: Paul H. Brookes
Publishing Company.
Field, J. (1976). Relation of young infants’ reaching behaviour to stimulus distance and solidity.
Developmental Psychology, 12, 444-448.
Foy, J. G., & Mann, V. (2003). Home literacy environment and phonological awareness in
preschool children: Differential effects for rhyme and phoneme awareness. Applied
Psycholinguistics, 24, 59–88.
Ganea, P. A., Allen, M. L., Butler, L., Carey, S., & DeLoache, J. S. (2009). Toddlers’ referential
understanding of pictures. Journal of Experimental Child Psychology, 104, 283-295.
Ganea, P. A., Bloom-Pickard, M., & DeLoache, J. S. (2008). Transfer between picture books and
the real world by very young children. Journal of Cognition and Development, 9, 46-66.
Ganea, P. A., Ma, L., & DeLoache, J. S. (2011). Young children's learning and transfer of
biological information from picture books to real animals. Child Development, 82, 1421-
1433.
Gelman, S. A., Coley, J. D., Rosengren, K. S., Hartman, E., & Pappas, A. (1998). Beyond
labeling. The role of maternal input in the acquisition of richly structured categories.
Monographs of the Society for Research in Child Development, 63(1, Serial No. 253).
Gentner, D., & Namy, L. L. (2004). The role of comparison in children's early word learning. In
D. G. Hall & S. R. Waxman (Eds.), Weaving a lexicon (pp. 533-568). Cambridge: MIT
Press.
Gentner, D., & Namy, L.L. (1999). Comparison in the development of categories. Cognitive
Development, 14, 487–513.
41
Graham, S. A., Kilbreath, C. S., & Welder, A. N. (2004). Thirteen-month-olds rely on shared
labels and shape similarity for inductive inferences. Child Development, 75, 409-427.
Harris, P. L., Kavanaugh, R. D., & Dowson, L. (1997). The depiction of imaginary
transformations: Early comprehension of a symbolic function. Cognitive Development, 12,
1-19.
Hauf, P. (2009). The interchange of self-performed actions and perceived actions in infants. In T.
Striano & V. Reid (Eds.), Social cognition: Development, neuroscience and autism (pp.
129–143). Blackwell.
Hayne, H. (2004). Infant memory development: Implications for childhood amnesia.
Developmental Review, 24, 33–73.
Hayne, H., & Herbert, J. (2004). Verbal cues facilitate memory retrieval during infancy. Journal
of Experimental Child Psychology, 89, 127–139.
Hayne, H., Herbert, J., & Simcock, G. (2003b). Imitation from television by 24- and 30-month-
olds. Developmental Science, 6, 254–261.
Herbert, J. S. (2011). The effect of language cues on infants’ representational flexibility in a
deferred imitation task. Infant Behavior & Development, 34, 632-635.
Herbert, J., & Hayne, H. (2000). Memory retrieval by 18—30-month-olds: Age-related changes
in representational flexibility. Developmental Psychology, 36, 473-484.
Jowkar-Baniani, G., & Schmuckler, M. A. (2011). Picture perception in infants: generalization
from two-dimensional to three-dimensional displays. Infancy, 16(2), 211–226.
Karrass, J., VanDeventer, M. C., & Braungart-Rieker, J. M. (2003). Predicting shared parent-
child book reading in infancy. Journal of Family Psychology, 17, 134–146.
Keates, J., & Graham, S.A. (2008). Category labels or attributes: Why do labels guide infants’
42
inductive inferences? Psychological Science, 19, 1287-1293.
Keates, J., Graham, S. A., & Ganea, P. A. (2010). Infants Transfer Nonobvious Properties from
Picture Books to Real-World Objects. Manuscript in revision.
Kuhl, P. K., Tsao, F., & Liu, H. (2003). Foreign language experience in infancy: Effects of short
term exposure and interaction on phonetic learning. Proceedings of the National
Academy of Sciences, 100, 9096–9101.
Payne, A. C., Whitehurst, G. J., & Angell, A. L. (1994). The role of home literacy environment
in the development of language ability in preschool children from low-income families.
Early Childhood Research Quarterly, 9, 427–440.
Pierroutsakos, S. L., & DeLoache, J. S. (2003). Infants’ manual exploration of pictorial objects
varying in realism. Infancy, 4, 141-156.
Preissler, M. A., & Carey, S. (2004). Do pictures and words function as symbols for 18- and 24-
month-old children? Journal of Cognition and Development, 5, 185-212.
Priessler, M. A., & Bloom, P. (2007). Two-year-olds appreciate the dual nature of pictures.
Psychological Science, 18, 1-2.
Rideout, V. J. (2011). Zero to eight: Children’s media use in America. Retrieved from the
Common Sense Media Inc. website: http://www.commonsensemedia.org/research/zero-
eight-childrens-media-use-america
Rose, S. A. (1977). Infants’ transfer of response between two-dimensional and three-dimensional
stimuli. Child Development, 48, 1086-1091.
Seehagen, S., & Herbert, J. S. (2010). The role of demonstrator familiarity and language cues on
infant imitation from television. Infant Behavior and Development, 33, 168-175.
Senechal, M., & Cornell, E. H. (1993). Vocabulary acquisition through shared reading
43
experiences. Reading Research Quarterly, 28, 360–375.
Simcock, G. & DeLoache, J. S. (2008). The effect of repetition on infants’ imitation from picture
books varying in iconicity. Infancy, 13, 687-697.
Simcock, G., & DeLoache, J. (2006). Get the picture? The effects of iconicity on toddlers’ re-
enactment from picture books. Developmental Psychology, 42, 1352-1357.
Simcock, G., & Dooley, M. (2007). Generalization of learning from picture books to novel test
conditions by 18- and 24-month-old children. Developmental Psychology 43, 1568-1578.
Simcock, G., Garrity, K., & Barr, R. (2011). The effect of narrative cues on infants’ imitation
from television and picture books. Child Development, 82, 1607–1619.
Suddendorf, T. (2003). Early representational insight: Twenty-four-month-olds can use a photo
to find an object in the world. Child Development, 74, 896–904.
Suddendorf, T., Simcock, G., & Nielsen, M. (2007). Visual self-recognition in mirrors and live
videos: Evidence for a developmental asynchrony. Cognitive Development, 22, 185–196.
Troseth, G. L., Pierroutsakos, S. L., & DeLoache, J. S. (2004). From the innocent to the
intelligent eye: The early development of pictorial competence. In R. V. Kail (Ed.),
Advances in child development and behaviour (Vol. 32, pp. 1-35). New York:
Elsevier/Academic Press.
Waxman, S. R. (2008). All in good time: How do infants discover distinct types of words and
map them to distinct kinds of meaning? In J. Colombo, P. McCardle, & L. Freund (Eds.),
Infant pathways to language: Methods, models, and research directions. Mahwah, NJ:
Lawrence Erlbaum Associates.
44
Zack, E., Gerhardstein, P., Meltzoff, A. N., & Barr, R. (in press). Fifteen-Month-Olds’ Transfer
of Learning between Touch Screen and Real-World Displays: Language Cues and
Cognitive Loads. Journal of Scandanavian Psychology.
45
Appendix A
Materials: Object Sets
Figure A1. The box object set.
Figure A2. The light object set.
Generalization non-target exemplar
Target object
Generalization target exemplar
Non-target object
Generalization non-target exemplar
Target object
Generalization target exemplar
Non-target object
46
Appendix B
Materials: Pictures from the Picture Books
Figure B1. Two pictures used in the labelling phase and the label comprehension phase. These
pictures show a ball and the box target object.
Picture #1 Picture #2 Picture #3
Picture #4 Picture #5 Picture #6 Figure B2. Sequence of pictures used in the nonobvious property phase. This sequence shows the
target object of the box object set.
47
Picture #1 Picture #2 Picture #3
Picture #4 Picture #5 Picture #6
Figure B3. Sequence of pictures used in the nonobvious property phase. This sequence shows the
target object of the box object set.
48
Appendix C
Dialogue for the Label and No Label Conditions
Dialogue for the Label Condition
Labelling book (box object)
Picture #1: “Look, it’s a ball.” Picture #2: “Look, this is a blicket. Wow, it’s a blicket. See, a blicket?” Picture #3: “Look, it’s a cup.” Picture #4: “Look, look at that. Wow, it’s that. See that?” Picture #5: “Look, it’s an apple.” Picture #6: “Look, this is a blicket. Wow, it’s a blicket. See, a blicket?” Picture #7: “Look, it’s a shoe.” Picture #8: “Look, look at that. Wow, it’s that. See that?” Picture #9: “Look, it’s a bottle.” Picture #10: “Look, this is a blicket. Wow, it’s a blicket. See, a blicket?” Picture #11: “Look, it’s a car.” Picture #12: “Look, look at that. Wow, it’s that. See that?” Picture #13: “Look, this is a blicket. Wow, it’s a blicket. See, a blicket?” Picture #14: “Look, look at that. Wow, it’s that. See that?”
Nonobvious property book (box object)
Target object pictures (note: dialogue for Picture #1 modified if these pictures were presented after the non-target object pictures) Picture #1: “Look. Heather has a blicket.” Picture #2: “Heather wonders what the blicket is!” Picture #3: “Look. Heather is going to pull the blicket.” Picture #4: “Look. Heather is pulling the blicket! Heather is pulling the blicket!” Picture #5: “Wow! The blicket opens up! The blicket opens up!” Picture #6: “Look what’s inside the blicket. Look what’s inside the blicket!”
Non-target object pictures (note: dialogue for Picture #1 modified if these pictures were presented before the target object pictures)
Picture #1: “Look. Heather has another toy.” Picture #2: “Heather wonders what this is!” Picture #3: “Look. Heather wonders what this is!” Picture #4: “Look. Heather is looking at this. Heather is looking at this!” Picture #5: “Wow! It looks orange! It looks orange!” Picture #6: “Look! Look at this! Look at this!”
49
Labelling book (light object)
Picture #1: “Look, it’s a bottle.” Picture #2: “Look, this is a fepan. Wow, it’s a fepan. See, a fepan?” Picture #3: “Look, it’s a car.” Picture #4: “Look, look at that. Wow, it’s that. See that?” Picture #5: “Look, it’s an apple.” Picture #6: “Look, this is a fepan. Wow, it’s a fepan. See, a fepan?” Picture #7: “Look, it’s a shoe.” Picture #8: “Look, look at that. Wow, it’s that. See that?” Picture #9: “Look, it’s a ball.” Picture #10: “Look, this is a fepan. Wow, it’s a fepan. See, a fepan?” Picture #11: “Look, it’s a cup.” Picture #12: “Look, look at that. Wow, it’s that. See that?” Picture #13: “Look, this is a fepan. Wow, it’s a fepan. See, a fepan?” Picture #14: “Look, look at that. Wow, it’s that. See that?”
Nonobvious property book (light object)
Target object pictures (note: dialogue for Picture #1 modified if these pictures were presented after the non-target object pictures) Picture #1: “Look. Heather has a fepan.” Picture #2: “Heather wonders what the fepan is!” Picture #3: “Look. Heather is going to push on the fepan.” Picture #4: “Look. Heather is pushing on the fepan! Heather is pushing on the fepan!” Picture #5: “Wow! The fepan lights up! The fepan lights up!” Picture #6: “Look the fepan lights up! The fepan lights up!”
Non-target object pictures (note: dialogue for Picture #1 modified if these pictures were presented before the target object pictures)
Picture #1: “Look. Heather has another toy.” Picture #2: “Heather wonders what this is!” Picture #3: “Look. Heather wonders what this is!” Picture #4: “Look. Heather is looking at this. Heather is looking at this!” Picture #5: “Wow! It looks purple! It looks purple!” Picture #6: “Look! Look at this! Look at this!”
50
Dialogue for the No Label Condition
Labelling book (box object)
Picture #1: “Look, it’s a ball.” Picture #2: “Look, look at that. Wow, it’s that. See that?” Picture #3: “Look, it’s a cup.” Picture #4: “Look, look at that. Wow, it’s that. See that?” Picture #5: “Look, it’s an apple.” Picture #6: “Look, look at that. Wow, it’s that. See that?” Picture #7: “Look, it’s a shoe.” Picture #8: “Look, look at that. Wow, it’s that. See that?” Picture #9: “Look, it’s a bottle.” Picture #10: “Look, look at that. Wow, it’s that. See that?” Picture #11: “Look, it’s a car.” Picture #12: “Look, look at that. Wow, it’s that. See that?” Picture #13: “Look, look at that. Wow, it’s that. See that?” Picture #14: “Look, look at that. Wow, it’s that. See that?”
Nonobvious property book (box object)
Target object pictures (note: dialogue for Picture #1 modified if these pictures were presented after the non-target object pictures) Picture #1: “Look. This is Heather. Heather has a toy!” Picture #2: “Heather wonders what this is!” Picture #3: “Look. Heather is going to pull this!” Picture #4: “Look. Heather is pulling this! Heather is pulling this!” Picture #5: “Wow! It opens up! It opens up!” Picture #6: “Look what’s inside! Look what’s inside!”
Non-target object pictures (note: dialogue for Picture #1 modified if these pictures were presented before the target object pictures)
Picture #1: “Look. Heather has another toy.” Picture #2: “Heather wonders what this is!” Picture #3: “Look. Heather wonders what this is!” Picture #4: “Look. Heather is looking at this. Heather is looking at this!” Picture #5: “Wow! It looks orange! It looks orange!” Picture #6: “Look! Look at this! Look at this!”
51
Labelling book (light object)
Picture #1: “Look, it’s a bottle.” Picture #2: “Look, look at that. Wow, it’s that. See that?” Picture #3: “Look, it’s a car.” Picture #4: “Look, look at that. Wow, it’s that. See that?” Picture #5: “Look, it’s an apple.” Picture #6: “Look, look at that. Wow, it’s that. See that?” Picture #7: “Look, it’s a shoe.” Picture #8: “Look, look at that. Wow, it’s that. See that?” Picture #9: “Look, it’s a ball.” Picture #10: “Look, look at that. Wow, it’s that. See that?” Picture #11: “Look, it’s a cup.” Picture #12: “Look, look at that. Wow, it’s that. See that?” Picture #13: “Look, look at that. Wow, it’s that. See that?” Picture #14: “Look, look at that. Wow, it’s that. See that?”
Nonobvious property book (light object)
Target object pictures (note: dialogue for Picture #1 modified if these pictures were presented after the non-target object pictures) Picture #1: “Look. This is Heather. Heather has a toy!” Picture #2: “Heather wonders what this is!” Picture #3: “Look. Heather is going to push on this!” Picture #4: “Look. Heather is pushing on this! Heather is pushing on this!” Picture #5: “Wow! It lights up! Look, it lights up!” Picture #6: “Look it lights up! It lights up!”
Non-target object pictures (note: dialogue for Picture #1 modified if these pictures were presented before the target object pictures)
Picture #1: “Look. Heather has another toy.” Picture #2: “Heather wonders what this is!” Picture #3: “Look. Heather wonders what this is!” Picture #4: “Look. Heather is looking at this. Heather is looking at this!” Picture #5: “Wow! It looks purple! It looks purple!” Picture #6: “Look! Look at this! Look at this!”
52
Appendix D
Interview Questions
1. What is the highest level of education that you have completed? What about child’s other
parent?
2. How many picture books (total) does child read per day?
a) How many of those picture books does child read with you or another adult?
b) How many of those picture books does child read by himself/herself?
3. (If applicable) When you read with child, are child’s siblings reading with you? What
percentage of the time would you say that is? What level books do you typically read, child’s
level or his/her sibling’s level?
4. What kinds of picture books do you typically read with child (e.g., Board books? Books with
large pictures and very little text, or storybooks?)
53
Appendix E
Supplemental Tables
Table E1. Infant demographic information as a function of age and condition.
Age
CDI
Books
Gender
M (SD) Range M (SD) Range M (SD) 18-month-olds No Label
Condition 18.57 (.25)
18.13 – 18.93
144 (137)
9 - 438 2.5 (1.5)
12 female 12 male
Label
Condition 18.51 (0.21)
18.14 – 18.8
62 (57)
8 -199 2.5 (1.4)
8 female 11 male
21-month-olds No Label
Condition 21.59 (0.23)
21.13 – 22.0
127 (100)
12 - 374
2.7 (1.5)
9 female 13 male
Label 21.48
(0.34) 21.0 – 22.0
228 (130)
30 - 428
2.5 (1.3)
12 female 10 male
Note: Age = age in months; CDI = number of words produced based on parental report on the MacArthur-Bates CDI; Books = number of books parents report reading with their infant daily.
Table E2. Maternal and paternal education as a function of condition (label vs. no label
condition).
Maternal Education
Paternal Education
No Label
Label
No Label
Label
Did not complete high school 0% 0% 4% 0%
High school diploma 20% 27% 27% 21%
Post-secondary education 63% 61% 56% 66%
Graduate studies 15% 10% 13% 5%
54
Table E3. Extension Trial: Logistic regression analysis predicting test performance from gender,
productive vocabulary, picture books read daily with a parent, age group, and condition.
Predictor
χ2 to Remove
df
Model χ2
Step 1 4.55 Gender 2.22 1 Productive vocabulary 0.83 1 Books read daily with parent 1.00 1
Step 2 7.42 Age group 2.71 1
Step 3 11.19* Condition 3.77** 1
* p = .048. ** p = .052
Table E4. Predictors of test performance on the extension trial.
Variable B Wald χ2 OR 95% CI
Gender 0.70 2.17 2.01 [0.79, 5.14]
Productive vocabulary 0.00 0.83 1.00 [1.00, 1.00]
Books 0.17 0.99 1.18 [0.85, 1.65]
Age group 0.78 2.67 2.18 [0.86, 5.58]
Condition 0.90 3.65 2.45 [0.98, 6.17]
(Constant) -1.55 4.77 0.21
Note: Books = Number of books read per day with a parent
55
Table E5. Generalization: Logistic regression analysis predicting test performance from gender,
productive vocabulary, picture books read daily with a parent, age group, and condition.
Predictor
χ2 to Remove
df
Model χ2
Step 1 7.00 Gender 0.52 1 Productive vocabulary 2.98 1 Books read daily with parent 2.38 1
Step 2 8.03 Age group 1.00 1
Step 3 10.41 Condition 2.38 1
Table E6. Predictors of test performance on the generalization trial.
Variable B Wald χ2 OR 95% CI
Gender 0.34 0.52 1.40 [0.57, 3.62]
Productive vocabulary 0.00 2.79 1.00 [1.00, 1.01]
Books 0.26 2.29 1.30 [0.93, 1.82]
Age group 0.48 1.00 1.61 [0.63, 4.12]
Condition 0.72 2.33 2.05 [0.82, 5.17]
(Constant) -1.50 4.47 0.22
Note: Books = Number of books read per day with a parent