Age related changes to perceptual surround suppression of moving stimuli

Abstract

Perceptual analogues of centresurround suppression have been applied as indirect measures of cortical inhibitory function in several clinical disorders. Two tasks have been used: a centresurround contrast perception task and a motion direction discrimination task, where the stimulus size and contrast is varied to measure surround suppression effects. The tasks are markedly different, yet previous literature implies that both measures indirectly assess inhibitory function and that results will be complementary. This is not the case for age-related effects on surround suppression, however, as previous reports using the different measures are conflicting. Here we use a low-spatial frequency, dr..