recognition. evolution of recognition procedural memory includes perceptual- motor skills automatic...
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Recognition
Visual Recognition Sensory Registration Feature Analysis
Patterns are constructed from features activated by visual inputs.
Shape Construction
Feature Analysisscene
textureobject
geons(parts)
feature
Visual Recognition Sensory Registration Feature Analysis Shape Construction
Comparison Input patterns are compared with patterns in memory.
Response A match is found and associated patterns in memory are
activated to create a meaningful representation of the world (perception/consciousness).
Selection & Integration The new representation is integrated into an
object/scene representation that is used to direct action.
Stages Of Recognition Feature Analysis Stage.
Comparison Stage.
Response Stage.
Selection & Integration Stage.
Vision Hearing
Occipital Cortex Temporal Cortex
Medial temporal Cortex:Limbic system + thalamus + surrounding
cortex
Temporal Cortex Prefrontal cortex
Stages of Recognition Process Comparison Stage
Input patterns are compared with patterns in memory.
Response Stage A match is found and associated patterns in memory
are activated to create a meaningful representation of the world (perception/consciousness).
Selection & Integration Stage The new representation is integrated into an
object/scene representation that is used to direct action.
Stages of Recognition Process Comparison Stage
Multiple patterns for the same input may be constructed. Each pattern is part of a different pathway to recognition.
Logogens compare input patterns with patterns in memory.
Response Stage Selection & Integration Stage
Redundant pathways in word recognition
dog
/dahg/
/ahg/
dog
/d/
og
d
c
a
b
a. Visual whole word
c,b. Auditory whole word
e,f,b. Letter-sound
e
e
f
f/dawg/
b
Stages of Recognition Process Comparison Stage
Multiple patterns for the same input may be constructed. Each pattern is part of a different pathway to recognition.
Masked priming reveals form effects when words share same pattern that provide evidence of the letter sequence pathway.
Logogens compare input patterns with patterns in memory.
Response Stage Selection & Integration Stage
Priming When two inputs are presented in
succession, the effect of one on the perception of the other is called priming. A facilitory effect is call (positive) priming and
an inhibitory effect is called negative priming. The effect of the first input on the second is
called (forward) priming and the effect of the second word on the first is called (backward) priming.
Priming Tasks & Measures Verbal report of what is seen.
Accuracy Choice reaction time. For example,
press the right button if the string is a word and the left button if it is a nonword. Reaction time & Accuracy
Naming. Read word you see aloud. Voice Onset Latency
Masked and Unmasked Primes
CAT
Presented
Observed
Unmasked:
CAT DOG
DOG
Presented
Observed
Backward Masked:
XXX DOGDOG
CATXXXX
Presented
Observed
Forward Masked:
CAT DOGDOG
XXXXXXX
Types of Priming Unmasked. For example, 60 millisecond
word prime immediately precedes target. Both prime and target are visible.
Masked. For example, 400 millisecond mask (XXXX) immediately precedes prime, which immediately precedes target. Only mask and target are visible.
Priming Relationships Masked primes activate
perceptual relationships (form priming). Shared onsets are effective primes, e.g., bell –
book, stray – stroke. Priming is cross-modal, so huevo primes wave in
bilinguals. Semantic/associative relationships
cat primes dog Boeing primes 747
Masked primes only operate over short, unfilled intervals.
Redundant pathways in word recognition
dog
/dahg/
/ahg/
dog
/d/
og
d
c
a
b
a. Visual whole word
c,b. Auditory whole word
e,f,b. Letter-sound
e
e
f
f/dawg/
b
Stages of Recognition Process Comparison Stage
Multiple patterns for the same input may be constructed. Each pattern is part of a different pathway to recognition.
Masked priming reveals form effects when words share same pattern that provide evidence of the letter sequence pathway.
Masked auditory priming provides evidence of the auditory whole-word pathway.
Logogens compare input patterns with patterns in memory.
Response Stage Selection & Integration Stage
Priming Relationships Masked primes activate
perceptual relationships (form priming). Shared onsets are effective primes, e.g., bell –
book, stray – stroke. Priming is cross-modal, so huevo primes wave in
bilinguals. Semantic/associative relationships
cat primes dog Boeing primes 747
Masked primes only operate over short, unfilled intervals.
Redundant pathways in word recognition
dog
/dahg/
/ahg/
dog
/d/
og
d
c
a
b
a. Visual whole word
c,b. Auditory whole word
e,f,b. Letter-sound
e
e
f
f/dawg/
b
Stages of Recognition Process Comparison Stage
Multiple patterns for the same input may be constructed. Each pattern is part of a different pathway to recognition.
Masked priming reveals form effects when words share same pattern that provide evidence of the letter sequence pathway.
Masked auditory priming provides evidence of the auditory whole-word pathway.
Word superiority effect reveals the visual whole-word pathway. A briefly presented letter is more likely to be perceived in the context
of a word than by itself. E/O versus READ/ROAD Logogens compare input patterns with patterns in memory.
Response, Selection, & Construction Stage Decision Stage
Redundant pathways in word recognition
dog
/dahg/
/ahg/
dog
/d/
og
d
c
a
b
a. Visual whole word
c,b. Auditory whole word
e,f,b. Letter-sound
e
e
f
f/dawg/
b
Stages of Recognition Process Feature Analysis Stage Comparison Stage
Multiple patterns for the same input may be constructed. Each pattern is part of a different pathway to recognition.
Masked priming Word superiority effect Frequency effect reveals visual whole-word pathway.
Briefly presented high frequency words more likely to be seen than low frequency words or nonwords.
Logogens compare input patterns with patterns in memory.
Response, Selection, & Construction Stage Decision Stage
Redundant pathways explanation of frequency effect
dog
/dahg/
/ahg/
dog
/d/
og
d
c
a
b
a. Visual whole word
c,b. Auditory whole word
e,f,b. Letter-sound
e
e
f
f/dawg/
b
Stages of Recognition Process Feature Analysis Stage Comparison Stage
Multiple patterns for the same input may be constructed. Each pattern is part of a different pathway to recognition.
Masked priming Word superiority effect Frequency effect reveals visual whole-word pathway. Whole-word pathway makes skilled reading possible.
When asked to detect Ts, readers miss many in high frequency words, e.g., the.
Logogens compare input patterns with patterns in memory.
Response, Selection, & Construction Stage Decision Stage
Evidence of Whole-Word Pathway
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Stages of Recognition Process Feature Analysis Stage Comparison Stage
Multiple patterns for the same input provide different pathways to recognition.
Logogens compare input patterns with patterns in memory.
Response Stage Selection Stage
Logogen Theory The brain is a continuously sensitive
receiver. When the match between an input an pattern in memory exceeds some criterion, perception of the pattern occurs.
Other names for logogens Perceptrons Demons (“Pandemonium”) Neural Net Connectionist Model
Logogen
boy boy
boy
boy
criterion
activationlevel
Stages of Recognition Process Feature Analysis Stage Comparison Stage
Multiple patterns for the same input provide different pathways to recognition.
Logogens compare input patterns with patterns in memory.
Repetition effect
Response Stage Selection & Integration Stage
Repetition effect
boy boyboy
b__ _o_ __y
boy
Activation from successive partialmatches can accumulate so repeatinga briefly presented item causes it tobe perceived more clearly.
Stages of Recognition Process Feature Analysis Stage Comparison Stage Response Stage
Logogens are part of semantic network. When a logogen responds associated
representations are also activated. Masked and unmasked semantic priming
reveals the spread of activation. Selection & Integration Stage
Responsescene
textureobject
geons(parts)
feature
point, triangle
star
wheel, compass
Priming Relationships Masked primes activate
Perceptual relationships (form priming).
Semantic/associative relationships cat primes dog Boeing primes 747
Masked primes only operate over short, unfilled intervals.
Priming Relationships Unmasked primes activate
semantic relationships, such as boy – girl. Unmasked primes can be effective
over long, filled intervals.
Explanation of semantic priming
cat dog
cat
cat Activation spreads among semantically related logogens
Nonvisual semantic information may influence visual recognition
Logogen system
dog
Motor Planning
dig
don
dot
/
dawg//ahg/
dog
/d/
og
d
Decision stage
/dawg/ /d/ /ahg/
d
dot
don
dig
cat
Stages of Recognition Process Comparison Stage Response Stage
Logogens are part of semantic network. Selection & Integration Stage
Some of the activated representations are combined into a single larger representation
Words into sentences Objects into a scene
Selection & Integrationscene
textureobject
geons(parts)
feature
Spatial context in visual recognition The elements of a scene
semantically prime each other Memory is a part of scene analysis
So we may construct a meaningful scene out of meaningless parts
Perception and recognition can not be separated into successive processing stages
Stages of Recognition Process Feature Analysis Stage Comparison Stage Response Stage
Logogens are part of semantic network. Selection and Integration Stage
A structural description is used to combine individual representations into a larger meaningful representation.
Structural Description A structural description describes
the relative locations of different categories of objects that are identified through feature representations. Faces, scenes
Structural Description A structural description describes the
relative locations of different categories of objects that are identified through feature representations.
Structural descriptions make it possible to recognize an infinite number of things categorically, hence semantically.
Structural Description A structural description describes the relative
locations of different categories of objects that are identified through feature representations.
Structural descriptions make it possible to recognize an infinite number of things categorically, hence semantically.
The categorical structural descriptions that are used to construct representations are part of procedural memory but the instance representations constructed with the structural descriptions are part of declarative memory.
Types of Visual Agnosia
LGN ofThalamus
Retina
OccipitalCortex
SurroundingVisual Cortex
MesialTemporalSubcortex
Inabilityto accessmemory
associativeagnosia
Inabilityto integrate
featuressimultagnosia
Response Selection& Integration
Feature Analysis & Comparison: Top-DownPerceptual Processing
Bottom upPerceptualProcessing
Summary Comparison between representation of
perceptual input and representations in memory Redundant pathways increase probability of match
Response includes multiple associated representations Priming, agnosia, and apraxia provide evidence of
specific pathways and associations Selection of context-appropriate
representation is integrated with structural description Orients you to place