Awake or asleep, we are basically under the regulation of two biological processes: sleep homeostasis, commonly known as ‘sleep pressure’, and the circadian rhythm, otherwise known as the ‘body clock,’ according to Medical Xpress.
The ventrolateral preoptic nucleus (VLPO) in the brain plays a critical role in falling—and staying—asleep, while the lateral posterior part of the hypothalamus contains neurons (brain cells) that play a role in the maintenance of staying awake, including orexin neurons in the lateral hypothalamic area(LHA) and histaminergic neurons in the tuberomammillary nucleus (TMN). To date, however, the precise connectivities among these cell populations remain unclear.
“In our study, we aimed to identify the important players implicated in arousal regulation,” explains Yuki Saito, who co-led a University of Tsukuba-centered study recently reported in the Journal of Neuroscience.
