Interaction between sensory and motor cortices is crucial for perceptual decision-making, in which intracortical inhibition might have an important role. We simulated a neural network model consisting of a sensory network (N_S) and a motor network (N_M) to elucidate the significance of their interaction in perceptual decision-making in association with the level of GABA in extracellular space: extracellular GABA concentration. Extracellular GABA molecules acted on extrasynaptic receptors embedded in membranes of pyramidal cells and suppressed them. A reduction in extracellular GABA concentration either in N_S or N_M increased the rate of errors in perceptual decision-making, for which an increase in ongoing-spontaneous fluctuations in subthreshold neuronal activity in N_M prior to sensory stimulation was responsible. Feedback (N_M-to-N_S) signaling enhanced selective neuronal responses in N_S, which in turn increased stimulus-evoked neuronal activity in N_M. We suggest that GABA in extracellular space contributes to reducing variability in motor cortex activity at a resting state and thereby the motor cortex can respond correctly to a subsequent sensory stimulus. Feedback signaling from the motor cortex improves the selective responsiveness of the sensory cortex, which ensures the fidelity of information transmission to the motor cortex, leading to reliable perceptual decision-making.

中文翻译：

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通过细胞外GABA减少静止状态下运动皮层活动的变异性，以实现可靠的感知决策。

感觉皮质和运动皮质之间的相互作用对于感知决策至关重要，其中皮质内抑制可能起重要作用。我们模拟了由感官网络（N _S）和运动网络（N _M）组成的神经网络模型，以阐明它们在感知决策中的相互作用与细胞外空间GABA的水平（细胞外GABA浓度）相关的重要性。细胞外GABA分子作用于锥体细胞膜中嵌入的突触外受体，并抑制它们。N _S或N _M中细胞外GABA浓度的降低增加了感知决策中的错误率，原因是感觉刺激之前N _M中亚阈值神经元活动的持续自发性波动增加。反馈（N _M -to N _S）信号增强了N _S中选择性神经元反应，进而增加了N _M中刺激诱发的神经元活动。我们建议细胞外空间中的GABA有助于减少静止状态下运动皮层活动的变异性，因此运动皮层可以正确响应随后的感觉刺激。运动皮层的反馈信号改善了感觉皮层的选择性响应能力，从而确保了信息传递到运动皮层的保真度，从而导致可靠的感知决策。