TY - JOUR T1 - Stream-Specific Feedback Inputs to the Primate Primary Visual Cortex JF - bioRxiv DO - 10.1101/2020.03.04.977264 SP - 2020.03.04.977264 AU - Frederick Federer AU - Seminare Ta’afua AU - Sam Merlin AU - Alessandra Angelucci Y1 - 2020/01/01 UR - http://biorxiv.org/content/early/2020/03/05/2020.03.04.977264.abstract N2 - The sensory neocortex consists of hierarchically-organized areas reciprocally connected via feedforward and feedback circuits. Feedforward connections shape the receptive field properties of neurons in higher areas within parallel streams specialized in processing specific stimulus attributes. Feedback connections, instead, have been implicated in top-down modulations, such as attention, prediction and sensory context. However, their computational role remains unknown, partly because we lack knowledge about rules of feedback connectivity to constrain models of feedback function. For example, it is unknown whether feedback connections maintain stream-specific segregation, or integrate information across parallel streams. Using selective viral-mediated labeling of feedback connections arising from specific cytochrome-oxidase stripes of macaque visual area V2, we find that feedback to the primary visual cortex (V1) is organized into parallel streams resembling the reciprocal feedforward pathways. These results suggest that specialized V2 feedback channels serve to modulate V1 responses to specific stimulus attributes, an organizational principle that could extend to other feedback pathways in sensory systems. ER -