The spatial extent of size adaptation effect in peripheral vision
Author
Altan, Ecem
Advisor
Boyacı, Hüseyin
Date
2019-07Publisher
Bilkent University
Language
English
Type
ThesisItem Usage Stats
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Abstract
It has been shown that prolonged exposure to a certain object size (i.e. size
adaptation) alters the subsequent size perception such that the size of the latter
appears more dissimilar to the adapted size (Pooresmaeili, Arrighi, Biagi, &
Morrone, 2013). However, how much of the visual space is in
uenced by the size
adaptation at a certain location remains unanswered. Here, in order to investigate
the spatial extent of the adaptation effect, we tested the size adaptation effect at
the adapted location and various non-adapted locations. In the first psychophysical
experiment, we showed a mid-sized adapter stimulus and tested its in
uence on
subsequent size perception at 5 locations. Results showed that the size perception
at non-adapted locations was in
uenced by the adapter, although not as much as
the effect at the adapted location. In the second experiment, we tested the size
aftereffect at 15 different locations and mapped out the perceived size distortions
over the visual field. Lastly, in the third experiment, we tested the effect of size
adaptation with ring-shaped stimuli and found a substantially large effect just as
in the second experiment. These findings overall suggest that the size adaptation
does not only have a local effect but also the size perception in consequence of
adaptation is being distorted throughout the visual field.