Linking polar angle asymmetries in visual perception and neural architecture
We are happy to welcome Dr Marc Himmelberg (New York University) for a CVL Talk. Marc will present his work on the relationship between polar angle asymmetries in visual perception and neural architecture.
Location
This talk will be held on Zoom. Please contact us at [email protected] for the link.
Abstract
Human visual cortex preserves the structure of the retinal image in cortical maps. fMRI has made it possible to measure these retinotopic maps from visually evoked activity in human visual cortex, including primary visual cortex (V1). Combining fMRI-derived retinotopic maps with MRI measurements of cortical surface area shows differences in the amount of V1 surface area – and thus neurons – representing different locations of the visual field. These location dependencies underlie differences in our perception throughout the visual field. For example, more V1 surface area represents the centre than the periphery of the visual field; this is matched by better visual performance at the centre than periphery. V1 surface area is also asymmetrically distributed with respect to polar angle. These cortical polar angle asymmetries have been linked to asymmetries in visual perception. I will present two experiments that have harnessed these cortical asymmetries to better understand the organisation of V1 and how it gives rise to visual perception. First, I will present work that shows how the polar angle representation of V1 changes between childhood and adulthood in a way that parallels developmental changes in visual perception. Second, I will present work that shows that individual differences in the structural organisation of V1 are tightly linked to individual differences in visual perception.
Biography
Marc Himmelberg is a fourth-year post-doc in the Department of Psychology and Center for Neural Science at New York University. He is jointly advised by Jonathan Winawer and Marisa Carrasco. Prior to his current position, Marc completed his PhD at the University of York under the guidance of Alex Wade. His research focuses on blending fMRI, psychophysics, and computational modeling to gain a deeper understanding of retinotopic maps in human early visual cortex. Marc’s primary interests lie in investigating how retinotopic maps represent visual space, how they encode visual information based on visual field location, and how individual differences in map structure contribute to variations in visual perception.