The role of V4 in object motion processing

Abstract

We rely heavily on our visual system for many functions. More specifically, the ability to process and track moving objects is of utmost importance. Much of the literature and conventional teachings in neuroscience hypothesize that the visual system has two functionally distinct pathways: a dorsal visual pathway for motion processing and a ventral visual pathway for form processing. However, this functional dichotomy is slowly eroding – specifically, many neurons along the ventral visual pathway demonstrate the ability to process the motion of objects. We focused our attention on ventral visual area V4, the most interconnected visual area of the visual system. We sought to understand how motion processing in V4 contrasts and complements motion processing in key dorsal stream areas, such as areas MT and MST. Many studies have shown the critical role that the dorsal visual stream plays in processing and perceiving motion information yet gaps remain in our knowledge of visual information. We find that neurons in V4 show selectivity for the motion of objects, rather than motion behind an aperture (i.e., V4 neurons preferentially encode the motion of stimuli with explicit boundaries translating across the visual field rather than static stimuli). These results demonstrate a novel and complementary motion processing mechanism in the ventral stream.