spatial perception presentation
TRANSCRIPT
Living in Two SpacesEffect of Attention on
Perception of Haptic Space
Rachel Franz & Siyan Zhao
Difference between Haptic Space and Physical SpaceWhat we sense is parallel when we can't see is different from what is physically parallel
Parallel in haptic space
Parallel in physical space
Kappers, A. M. (2007). Haptic space processing–allocentric and egocentric reference frames. Canadian Journal of Experimental Psychology, 61(3), 208-218.
Our Question
How does attention affect what we perceive as parallel by touch alone?
Systematic Deviations
Pattern is always the same
Why do we see this pattern?
First, some definitions:
Egocentric reference frame
Mental representation of space from our own perspective
Why do we see this pattern?
Allocentric reference frame:
Our mental representation of space that is independent of our perspective
...same house, different representations.
Both reference frames contribute to our perception of what is parallel
Why do we see this pattern?
Kappers, A. M. (2004). The contributions of egocentric and allocentric reference frames in haptic spatial tasks. Acta psychologica, 117(3), 333-340.
Why do we see this pattern?
In this task:
Allocentric reference frame-same as physical space, more accurate
Egocentric reference frame-less accurate
Where is the egocentric reference frame located?
For 8 out of 10 participants, the hand centered model was weighted more
The oblique effectInteresting effect occurs at 45 and 135 degrees
90135
Allocentric reference frame
4590
Egocentric
reference
frame
Allocentric reference frame
The oblique effectInteresting effect occurs at 45 and 135 degrees
Participants more accurate for oblique orientations!
4590
Egocentric
reference
frame
Allocentric reference frame
How were reference frames manipulated in other studies?
Zuidhoek et al. (2003)Time delay -> + allocentric
Newport et al. (2002)Vision -> + allocentric
Our study
Attention -> + egocentric
4590
Egocentric
reference
frame
Allocentric reference frame
Based on our question..
How does attention affect what we perceive as parallel by touch alone?
Hypothesis
● Attention causes subjects to place more importance on their egocentric reference frame
Method - IV, DV
● Within-subject design● Independent Variable: Attention● Dependent Variable: Weight of allocentric
and egocentric reference frame
Method - Setup
Target bar (static)Test Bar
Participants sat here
Method - Setup
Target bar (static)Test Bar
Participants sat here
Method - Operationalization
● IV: To focus participants' attention on their hands, we trace the outline of their hands in treatment condition (~20 sec). For control condition, participants sat for 20 seconds
● DV: The degree of deviation of the test bar from the target bar
Target bar Test bar
Method - Participants
19 Carnegie Mellon University Students:12 were from a Research Method class7 outside of the class
ResultThe treatment group performed significantly better (p = 0.02, t(18) = 2.54)
Large variation supports oblique effect
Some people performed better
Treatment
Control
Conclusion● Blindfolded participants who had their
hands traced had a better sense when objects were parallel.
ConclusionParticipants put more weight on their egocentric reference frame after we traced their hands.
4590
Egocentric
reference
frame
Allocentric reference frame
Alternative Explanation
Attention caused increased awareness of hand orientations
Limitations
Who gave more weight to their egocentric reference frame?
Gender?
Directions for future research
Did the allocentric participants also give more weight to egocentric reference frame?
What happens when people don't attend to spatial properties of their hands?
Contribution
The egocentric reference frame can be manipulated
Attention can affect egocentric reference frame