Virtual fMRI brown bag: August 13, 2021

Please join us for a talk given by Qi Zhu, a researcher at NeuroSpin.

Time: 12:00-1:00pm

Place: Zoom - link distributed via email

Ultra-high-resolution functional MR imaging of macaque visual cortex 

Abstract: Despite more than half a century of research since the discovery of the extrastriate visual cortex, there is still a fierce ongoing debate concerning the topographic layout of the dorsal visual cortex in primates. In both macaques and humans, the prominent model proposed a simple V3d extending along the entire rostral border of V2d. This model contrasts sharply with other models based on and from New World monkeys, which typically have a much larger number of quadrant representations in dorsal visual cortex immediately rostral to V2d. In this talk, I will present you a summary of all these debates, and recent studies we performed in macaques using fMRI at ultra-high-resolution using implanted coils. I will show a substantially different retinotopic organization of dorsal third and fourth visual areas in macaques compared with widely accepted models, yet a remarkably similar layout in Old and New World monkeys. I will argue that this organization largely reconciles most reported discrepancies concerning the visuotopic organization of nonhuman primate caudo-dorsal occipital cortex, which strongly indicating that this cortex is evolutionary largely conserved.