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Quantifying Infra-slow Dynamics of Spectral Power and Heart Rate in Sleeping Mice
Published on: August 2, 2017
Mammalian sleep dynamics: how diverse features arise from a common physiological framework
Andrew J K Phillips1, Peter A Robinson, David J Kedziora
1School of Physics, University of Sydney, Sydney, Australia. ajphillips@partners.org
Plos Computational Biology
|June 30, 2010
Summary
A unified model explains diverse mammalian sleep patterns by adjusting two parameters in the sleep-wake switch. This framework reveals conserved core mechanisms across species, with evolutionary modifications accounting for variations like unihemispheric sleep.
Area of Science:
- Neuroscience
- Computational Biology
- Evolutionary Biology
Background:
- Mammalian sleep exhibits significant interspecies variation, from rodents to cetaceans.
- Sleep patterns are typically regulated by homeostatic and circadian drives, but universality across mammals is unknown.
Purpose of the Study:
- To determine if a single quantitative model can explain diverse mammalian sleep patterns.
- To investigate the evolutionary basis of interspecies sleep variations.
Main Methods:
- A quantitative model of the sleep-wake switch was adapted by altering two key parameters.
- The model's ability to reproduce sleep patterns for 17 species across 7 mammalian orders was tested.
- An additional inhibitory connection was modeled to explain unihemispheric sleep.
Main Results:
- Minor parameter adjustments in the model successfully replicated typical sleep patterns for 17 diverse mammalian species.
- Parameter variations correlated with brain volume and surface area assumptions for homeostatic processes.
- Modeling an inhibitory neural connection explained unihemispheric sleep and fur seal adaptations.
Conclusions:
- A single, adaptable model demonstrates that core mammalian sleep-wake mechanisms are conserved across orders.
- Interspecies differences in sleep patterns likely arise from slight evolutionary modifications of these core mechanisms.
- The study provides a testable hypothesis for the evolution and function of unihemispheric sleep.
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