Abstract
We investigated how the statistics of the recently viewed environment affect the way that the visual brain processes information. Contrary to the oblique effect of orientation processing (Apelle, Psychol. Bull., 1972) research has determined that, when presented in a naturalistic context, human perception of horizontal orientations is actually worst and oblique orientations are perceived best – the horizontal effect (e.g., Essock,et al., Vis. Res., 2003). This indicates a relationship between encoding of orientation and natural scene statistics; the differential perception of orientations in broadband images closely matches their differential representation in the natural environment (Essock, Haun, & Kim, JOV., 2009). However, the hypothesis that this relationship likely evolved across millennia to make the visual system an efficient information-transmitting system needs to be evaluated in light of recent research showing the modification of orientation perception by exposure to altered environments (Bao & Engel, Proc Natl Acad Sci., 2012; Zhang, et.al., Cur. Bio., 2009) and studies showing later development of adult-like orientation processing (Ellemberg, Hansen, & Johnson, Vis. Res. 2012; Ellemberg, et. al., Percep., 2012). To assess the effect of recent exposure on broadband orientation processing, we modified the orientation content subjects viewed via FFT filtering of their environment in near-real-time. Subjects viewed a filtered visual world via HMD, and the perceptual strength of oriented content (i.e., the horizontal effect) was measured. Results show that experience in an isotropic environment alters anisotropic processing: all subjects show a typical horizontal effect pattern in pre-test, but not in post-test and most show a much more isotropic pattern of orientation perception after adaptation. Moreover, experience in other anisotropic environments adjusts orientation perception in a similarly predictable manner. This change in perception indicates not only that orientation processing is plastic, but that it is related in a predictable way to an observer’s recent visual environment.
Meeting abstract presented at VSS 2015