Experimental Psychology Seminar
Jason Rihel (Division of Biosciences, UCL)
“A neuropeptide system that senses and releases sleep pressure”
In John Keats’s poem, “To Sleep”, he exhorts Sleep to “turn the key deftly in the oiled wards”, allowing him a restful slumber. Although we have known that sleep pressure builds up the longer we stay awake, neither the sleep pressure signals (the “key”) nor where in the brain (the “oiled wards”) these are sensed are well understood. In this talk, I will present evidence from genetic, neuronal imaging, and behavioral experiments using larval zebrafish that a hypothalamic inhibitory neuropeptide called Galanin is critical for responding to sleep pressure signals. Moreover, our data suggest that the intensity of neuronal activity and not just the duration of wakefulness is an important driver of sleep pressure. I will discuss the implications of these findings on our understanding of the nature of sleep drive. I will also describe how this circuit may be impacted by other sleep-regulatory signals, including those involved in neurodegenerative diseases.