Title: Experience Dependent Object Perception
1Experience Dependent Object Perception
- Richard Zemel
- Computer Science Department
- University of Toronto
2Two Sets of Experiments
1. To what degree is object perception
invariant? Familiarity Naming Reference-Frames
.2. What is the role of experience in
completion? Novel occluded shapes Occlusion
without occluders
3Collaborators
- Mary Peterson
- Larry James
- Dave Towers
- Marlene Behrmann
- Mike Mozer
- Daphne Bevalier
4Sample Stimuli
5Familiarity Methods
- Training Phase 16 stimuli, fixed locations
- passive viewing (6 blocks)
- active old/new discrimination (2 blocks)
- Testing Phase (2 blocks)
- new trials -- 16 distractors
- old trials -- half of learned objects
- stay in learned location
- shift to diagonally-opposite location
6Familiarity Accuracy
7Familiarity RT
8Naming Methods
- Training Phase 8 rounds 8 named objects
- passive 2 blocks (160 ms) GIX
(500 ms) - active 1 block (160 ms) keyboard
(feedback)
- Testing Phase 6 rounds half shift sides, half
stay - passive 2 blocks
- active 1 block (no feedback)
9Naming Accuracy
10Reference-Frames Variations
11Reference-Frames Methods
- Training Phase 2 rounds 16 objects
- passive 6 blocks
- active 2 blocks
old/new (f-back)
- Testing Phase same/different retinal screen
locs - active 2 blocks
old-new
12 Reference-Frames Conditions
13Reference-Frames Results
14Experience Dependence When Objects Irrelevant?
- Many properties of objects not invariant, but
rather depend on experience - Evidence from experiments in which object memory
directly relevant to task - Is experience important when the object is
unnecessary to accomplish task?
15Object attention occlusion
16Object attention sensitive to layout
17Object attention experience
18Experience affects object attention
19Completion without occluder?
Subjects complete fragments given experience with
potential linking shape Is evidence of
occlusion required?
20Completion w/o occluder Methods
- Phase 2 V displays
- Phase 3 Ends and Vs
21Missing Occluder Results
22Conclusions
- Memories of novel objects are specific to learned
locations - Both retinal screen coordinates involved, so
not just episodic memory
- Object attention applies to recently viewed novel
shapes - Experience-dependent object effects can apply to
fragments without occluder
23Current Directions
- Duration of effects
- Generalization
- Amount of experience required