Selective Activation of Cholinergic Basal Forebrain Neurons Induces Immediate Sleep-wake Transitions

• DOI: 10.1016/j.cub.2014.02.011
• Publication Date: 2014-03-08T00:31:10Z
• Authors: Yong Han; Yu-feng Shi; Wang Xi; Rui Zhou; Zhi-bing Tan; Hao Wang; Xiao-ming Li; Zhong Chen; Guoping Feng; Minmin Luo; Zhi-li Huang; Shumin Duan; Yan-qin Yu
• Keywords: Sleep; Forebrain; Basal (medicine)

The basal forebrain (BF) plays a crucial role in cortical activation [1, 2]. However, the exact role of cholinergic BF (ch-BF) neurons in the sleep-wake cycle remains unclear [3, 4]. We demonstrated that photostimulation of ch-BF neurons genetically targeted with channelrhodopsin 2 (ChR2) was sufficient to induce an immediate transition to waking or rapid eye movement (REM) sleep from slow-wave sleep (SWS). Light stimulation was most likely to induce behavioral arousal during SWS, but not during REM sleep, a result in contrast to the previously reported photostimulation of noradrenergic or hypocretin neurons that induces wake transitions from both SWS and REM sleep. Furthermore, the ratio of light-induced transitions from SWS to wakefulness or to REM sleep did not significantly differ from that of natural transitions, suggesting that activation of ch-BF neurons facilitates the transition from SWS but does not change the direction of the transition. Excitation of ch-BF neurons during wakefulness or REM sleep sustained the cortical activation. Stimulation of these neurons for 1 hr induced a delayed increase in the duration of wakefulness in the subsequent inactive period. Our results suggest that activation of ch-BF neurons alone is sufficient to suppress SWS and promote wakefulness and REM sleep.