State-dependent intracortical connectivity in the mouse visual cortex

丘脑皮层回路在清醒时处理感觉输入，并自发地产生睡眠特征的同步活动。活动依赖的可塑性在发育过程中塑造丘脑皮质通路，但需要什么类型的活动仍然未知。在这里，我们报告了在睡眠过程中改变视觉处理，增强神经元连接，并通过抑制其调节，使用多单单位记录在睡眠-觉醒周期的行为小鼠的视觉皮层。慢波睡眠（SWS）期间的视觉反应与清醒时不同。交叉相关分析显示SWS过程中神经元之间的功能连接增强。此外，增强是显着的，即使在假定的单突触皮质内连接。在GABA合成酶基因敲除小鼠保留潜在的皮质可塑性，睡眠的单突触增强严重受损，可逆地恢复使用安定的抑制性传输的促进。我们的研究结果表明，SWS的功能连接是由抑制系统控制的，并参与了皮质可塑性的表达。

Thalamocortical circuits process sensory input during waking, and spontaneously generate synchronized activity characteristic of sleep. Activity-dependent plasticity shapes thalamocortical pathway during development, however what types of activity are required remains unknown. Here we report altered visual processing during sleep, enhancement of neuronal connectivity, and its regulation by inhibition, using multiple-single unit recording across sleep-wake cycles in the visual cortex of behaving mice. Visual response during slow-wave sleep (SWS) was distinct from that of waking. Enhancement of functional connectivity among neurons during SWS was revealed by cross-correlation analysis. Moreover, the enhancement was significant even in putative monosynaptic intracortical connections. In GABA-synthetic enzyme knockout mice which retain a latent cortical plasticity, the monosynaptic enhancement by sleep was severely impaired, and reversibly restored by facilitation of inhibitory transmission using diazepam. Our results suggest functional connectivity in SWS is controlled by inhibitory system and is involved in expression of cortical plasticity.