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What is Sleep?

  • About
  • Program
  • Participants
  • Summary
Group photo

Date: November 18, 2019 - November 20, 2019

Meeting Synopsis

Sleep is ubiquitous and a necessity for virtually any organism with some form of a brain. Yet the dominant causes and functions of sleep remain a mystery within species, across species, across development, and across daily cycles of night and day. Moreover, understanding how these different time scales and potentially different functions of sleep at each time scale are able to interact and integrate is a major challenge. For instance, sleep times decrease with body size across species and also decrease with body size as organisms grow from birth to adult. However, the rate of change with body size is very different across phylogeny than it is across ontogeny. In addition, it is intriguing to consider how biological and physical clocks can be coupled together. Biological clocks change with species and age, but the physical clocks of the sun, moon, and seasons are experienced to be the same by all organisms. This is further complicated by the fact that some species live only a few days while others can live for 200 years. Consequently, this working group will focus on the causes, time scales, and consequences of sleep for the following aspects:

  • Changes in sleep time across species (evolution and physiology)
  • Changes in sleep time as we grow (early and late development)
  • Changes in sleep time as we age during adulthood
  • Changes in when we sleep (circadian, consolidated, etc.)
  • Changes in sleep time within a single sleep cycle (REM and non-REM)

 

This event is supported by the James S. McDonnell Foundation Grant Number 220020491, Adaptation, Aging, and the Arrow of Time. Any opinions, findings, conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the James S. McDonnell Foundation.




  • Resources
  • Paradoxical timing of the circadian rhythm of sleep propensity serves to consolidate sleep and wakefulness in humans
  • Parvalbumin-expressing interneurons coordinate hippocampal network dynamics required for memory consolidation
  • Peak of circadian melatonin rhythm occurs later within the sleep of older subjects
  • Probabilistic sleep architecture models in patients with and without sleep apnea
  • Quantifying Human Circadian Pacemaker Response to Brief, Extended, and Repeated Light Stimuli over the Phototopic Range
  • A Period2 Phosphoswitch Regulates and Temperature Compensates Circadian Period
  • A Simpler Model of the Human Circadian Pacemaker
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