Purchase this article with an account.
Alice R. Albrecht, Brian Scholl; Perceptual size averaging: It's not just for circles anymore. Journal of Vision 2012;12(9):930. doi: 10.1167/12.9.930.
Download citation file:
© 2016 Association for Research in Vision and Ophthalmology.
Much recent research has explored the phenomenon of perceptual averaging: beyond constructing representations of individual objects, the visual system also computes statistical summaries of scenes (perhaps as a way of coping with capacity limitations). For example, observers are able to efficiently and accurately report the average size of an array of discs. To date, however, the displays used in such studies have been homogeneous in several ways that are not reflective of real-world scenes. For example, the arrays in such experiments have always used displays that contain identical shapes, varying only in size. To explore perceptual averaging for heterogeneous displays, observers viewed 1-second arrays of either pacmen or wedges (equated for area), where the angular extent of the wedges (or of the 'missing' wedges from pacmen) varied within each array. Observers reported the average area of such arrays using an adjustable test shape that matched the array shapes (e.g. using a constant-radius wedge whose angular sweep could be adjusted, or using a constant-angle wedge whose radius could be adjusted). Observers were no less accurate at averaging in this situation than when they reported the average area of an array of discs using a test disc. However, there was a marked cost of adding a different kind of heterogeneity at test: for example, when reporting average area using a test disc, observers are more accurate for arrays filled with discs than for arrays filled with either pacmen or wedges. Thus we see that perceptual averaging is relatively unaffected by some types of heterogeneity (e.g. within-array shape differences), but can be frustrated by others (e.g. heterogeneity across initial arrays vs. test shapes). These and other manipulations suggest that perceptual averaging is well adapted to at least some of the kinds of heterogeneity that are characteristic of real-world visual experience.
Meeting abstract presented at VSS 2012
This PDF is available to Subscribers Only