TY - JOUR
T1 - Columnar processing of border ownership in primate visual cortex
AU - Franken, Tom P.
AU - Reynolds, John H.
N1 - Funding Information:
This research was supported by NEI core grant for vision research P30-EY019005 to The Salk Institute for Biological Studies. We thank Dr. Edward Callaway, Dr. Anirvan Nandy, and Dr. Zachary Davis for helpful discussions. We thank Dr. Mathias LeBlanc, Dr. Sean Adams, and Ms. Catherine Williams for excellent animal care.
Funding Information:
Brain and Behavior Research Foundation NARSAD Young Investigator Grant Tom P Franken National Eye InstituteK99EY031795.
Publisher Copyright:
© Franken and Reynolds.
PY - 2021/11
Y1 - 2021/11
N2 - To understand a visual scene, the brain segregates figures from background by assigning borders to foreground objects. Neurons in primate visual cortex encode which object owns a border (border ownership), but the underlying circuitry is not understood. Here, we used multielectrode probes to record from border ownership-selective units in different layers in macaque visual area V4 to study the laminar organization and timing of border ownership selectivity. We find that border ownership selectivity occurs first in deep layer units, in contrast to spike latency for small stimuli in the classical receptive field. Units on the same penetration typically share the preferred side of border ownership, also across layers, similar to orientation preference. Units are often border ownership-selective for a range of border orientations, where the preferred sides of border ownership are systematically organized in visual space. Together our data reveal a columnar organization of border ownership in V4 where the earliest border ownership signals are not simply inherited from upstream areas, but computed by neurons in deep layers, and may thus be part of signals fed back to upstream cortical areas or the oculomotor system early after stimulus onset. The finding that preferred border ownership is clustered and can cover a wide range of spatially contiguous locations suggests that the asymmetric context integrated by these neurons is provided in a systematically clustered manner, possibly through corticocortical feedback and horizontal connections.
AB - To understand a visual scene, the brain segregates figures from background by assigning borders to foreground objects. Neurons in primate visual cortex encode which object owns a border (border ownership), but the underlying circuitry is not understood. Here, we used multielectrode probes to record from border ownership-selective units in different layers in macaque visual area V4 to study the laminar organization and timing of border ownership selectivity. We find that border ownership selectivity occurs first in deep layer units, in contrast to spike latency for small stimuli in the classical receptive field. Units on the same penetration typically share the preferred side of border ownership, also across layers, similar to orientation preference. Units are often border ownership-selective for a range of border orientations, where the preferred sides of border ownership are systematically organized in visual space. Together our data reveal a columnar organization of border ownership in V4 where the earliest border ownership signals are not simply inherited from upstream areas, but computed by neurons in deep layers, and may thus be part of signals fed back to upstream cortical areas or the oculomotor system early after stimulus onset. The finding that preferred border ownership is clustered and can cover a wide range of spatially contiguous locations suggests that the asymmetric context integrated by these neurons is provided in a systematically clustered manner, possibly through corticocortical feedback and horizontal connections.
UR - http://www.scopus.com/inward/record.url?scp=85120894505&partnerID=8YFLogxK
U2 - 10.7554/eLife.72573
DO - 10.7554/eLife.72573
M3 - Article
C2 - 34845986
AN - SCOPUS:85120894505
SN - 2050-084X
VL - 10
JO - eLife
JF - eLife
M1 - e72573
ER -