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Cholinergic manipulations affect sensory responses but not attentional enhancement in macaque MT.

ABSTRACT:

Background

Attentional modulation in the visual cortex of primates is characterized by multiplicative changes of sensory responses with changes in the attentional state of the animal. The cholinergic system has been linked to such gain changes in V1. Here, we aim to determine if a similar link exists in macaque area MT. While rhesus monkeys performed a top-down spatial attention task, we locally injected a cholinergic agonist or antagonist and recorded single-cell activity.

Results

Although we confirmed cholinergic influences on sensory responses, there was no additional cholinergic effect on the attentional gain changes. Neither a muscarinic blockage nor a local increase in acetylcholine led to a significant change in the magnitude of spatial attention effects on firing rates.

Conclusions

This suggests that the cellular mechanisms of attentional modulation in the extrastriate cortex cannot be directly inferred from those in the primary visual cortex.

SUBMITTER: Veith VK

PROVIDER: S-EPMC7967954 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Cholinergic manipulations affect sensory responses but not attentional enhancement in macaque MT.

Veith Vera Katharina VK Quigley Cliodhna C Treue Stefan S

BMC biology 20210316 1

<h4>Background</h4>Attentional modulation in the visual cortex of primates is characterized by multiplicative changes of sensory responses with changes in the attentional state of the animal. The cholinergic system has been linked to such gain changes in V1. Here, we aim to determine if a similar link exists in macaque area MT. While rhesus monkeys performed a top-down spatial attention task, we locally injected a cholinergic agonist or antagonist and recorded single-cell activity.<h4>Results</h ...[more]

PMID: 33726757

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