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Surround Integration Organizes a Spatial Map during Active Sensation.

ABSTRACT: During active sensation, sensors scan space in order to generate a representation of the outside world. However, since spatial coding in sensory systems is typically addressed by measuring receptive fields in a fixed, sensor-based coordinate frame, the cortical representation of scanned space is poorly understood. To address this question, we probed spatial coding in the rodent whisker system using a combination of two-photon imaging and electrophysiology during active touch. We found that surround whiskers powerfully transform the cortical representation of scanned space. On the single-neuron level, surround input profoundly alters response amplitude and modulates spatial preference in the cortex. On the population level, surround input organizes the spatial preference of neurons into a continuous map of the space swept out by the whiskers. These data demonstrate how spatial summation over a moving sensor array is critical to generating population codes of sensory space.

SUBMITTER: Pluta SR

PROVIDER: S-EPMC5512457 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Surround Integration Organizes a Spatial Map during Active Sensation.

Pluta Scott R SR Lyall Evan H EH Telian Greg I GI Ryapolova-Webb Elena E Adesnik Hillel H

Neuron 20170511 6

During active sensation, sensors scan space in order to generate a representation of the outside world. However, since spatial coding in sensory systems is typically addressed by measuring receptive fields in a fixed, sensor-based coordinate frame, the cortical representation of scanned space is poorly understood. To address this question, we probed spatial coding in the rodent whisker system using a combination of two-photon imaging and electrophysiology during active touch. We found that surro ...[more]

PMID: 28504117

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