Poster D117, Monday, March 27, 8:00 – 10:00 am, Pacific Concourse
Visual-Field Specific Category Learning
Luke Rosedahl1, Miguel Eckstein1, Greg Ashby1; 1University of California Santa Barbara
Although perceptual discrimination has often been found to be visual-field dependent, object recognition is commonly thought to be visual-field invariant. Here, the first fully controlled instance of visual-field specific category learning (using eye tracking) is described, supporting some level of visual-field dependence. Forty subjects performed a four-category categorization task during eye tracking. Subjects wore an eye patch over one eye and saw Gabor discs presented 5 degrees peripheral for 150ms. Any eye movement aborted the trial. Subjects trained with feedback in the right peripheral field of the right eye followed by testing without feedback in the same location and eye. Subjects were then tested without feedback with the stimulus moved to one of two locations: the left peripheral field of the same eye or the right peripheral field of the other (left) eye. This latter condition tests whether any change in stimulus condition affects performance. The results showed a significant (p < .01) decrease in performance when the stimulus was moved to the untrained location of the trained eye (i.e., when the stimulus was moved from the right peripheral field to the left peripheral field of the right eye) and no change for the other condition. This demonstrates that some types of category learning occur in a visual-field specific manner. Although performance dropped significantly when the stimulus was moved to the new location on the trained eye, it remained well above chance, showing that some position-invariant learning occurred as well. This might account for previous reports of visual-field invariant learning.
Topic Area: PERCEPTION & ACTION: Vision