Topic: orexin neurons

Sleep deprivation is thought to affect 30% of the population worldwide. Yet our understanding of how sleep disorders develop, how to treat them, and how to prevent cognitive impairment associated with lack of sleep remains limited. Previous studies from our lab have suggested that orexinergic inputs to the hippocampus are more active when mice are sleep deprived, but whether this plays a role in the mechanism for disruption of hippocampal memories during sleep deprivation is unknown. We have used excitatory and inhibitory chemogenetic manipulations to bidirectionally modulate orexin neurons' a

Orexin neurons originate in the lateral hypothalamus, receive many inputs, and project throughout the brain. This puts them in an ideal position to integrate large amounts of information and signal them toward desired targets. We hypothesized that arousal, which impacts a variety of internal states and behaviours, could be one of these signals that orexin neurons transmit. To test this, we investigated the causal and correlative links between orexin neurons and pupil size, which is often taken as a readout of arousal. Optogenetic stimulation, 2-photon imaging, photometry, ablation, and pharmac