Abstract
The dorsomedial visual area (DM), a subdivision of extrastriate cortex located near the dorsal midline, is characterized by heavy myelination and a relative emphasis on peripheral vision. To date, DM remains the least understood of the three primary targets of projections from the striate cortex (V1) in New World monkeys. Here, we characterize the responses of DM neurons in anaesthetized marmosets to drifting sine wave gratings. Most (82.4%) cells showed bidirectional sensitivity, with only 6.9% being strongly direction selective. The distribution of orientation sensitivity was bimodal, with a distinct population (corresponding to over half of the sample) formed by neurons with very narrow selectivity. When compared with a sample of V1 units representing a comparable range of eccentricities, DM cells revealed a preference for much lower spatial frequencies, and higher speeds. End inhibition was extremely rare, and the responses of many cells summated over distances as large as 30 degrees. Our results suggest clear differences between DM and the two other main targets of V1 projections, the second (V2) and middle temporal (MT) areas, with cells in DM emphasizing aspects of visual information that are likely to be relevant for motor control.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.