“Contextual responses drive a unique laminar signature in human V1”.

Jurjen Heij, Luisa Raimondo, Jeroen C.W. Siero, Wietske van der Zwaag, Tomas Knapen, Serge O. Dumoulin

Abstract Neuronal populations in visual cortex integrate stimulus-driven input from the retina with contextual input from neighboring neurons, each targeting distinct cortical layers. Using targeted line-scanning fMRI, we recorded depth-resolved responses in human visual cortex to stimuli tailored to each participant’s population receptive field (pRF). Stimuli in the pRF center evoked increasing responses toward the pial surface with a smaller middle-depth peak, consistent with feedforward input. Large surround stimuli elicited activity in superficial and deep layers, where descending connections terminate. Medium stimuli produced a more complex pattern, possibly reflecting overlap between stimulus- and context-related processes. Large surround stimuli also evoked a negative deflection at middle depths, potentially reflecting lateral inhibition. These findings bridge invasive animal work with human neuroimaging and support non-invasive manipulation of cortical computations.