Modulations associated with sleep
The model has been shown to accurately reproduce EEG behaviour
in a variety of states of vigilance. In its present form
however, the model is static with regards to these states.
Modelling the evolution of relevant model parameters will
allow the model to traverse the sleep-wake cycle in a realistic
fashion. This extension will involve co-ordinating the effects
of the circadian rhythm and sleep homeostasis on corticothalamic
interactions. Further refinement will incorporate the 90
minute ultradian rhythm responsible for the REM-NREM sleep
cycle as well as variations in wakeful activity. This will
require modeling of competition between 'REM-on' and 'REM-off'
neurons of the brainstem. Such an extension to the model
will allow for a greater understanding of the human sleep-wake
cycle with possible applications to sleep disorders.
Key References
Jewett ME, Kronauer RE. Refinement of a Limit Cycle Oscillator
Model of the Effects of Light on the Human Circadian Pacemaker. J
Theor Biol, 1998; 192: 455-465
Achermann P, Borbely A. Simulation of daytime vigilance
by the additive interaction of a homeostatic and a circadian
process. Biol Cybern. 1994; 71: 115-121
Achermann P, et al. A Model of Human Sleep Homeostatis Based
on EEG Slow-Wave Activity: Quantitative Comparison of Data
and Simulations. Brain Research Bulletin, 1993;
31: 97-113
Pace-Schott EF, Hobson JA. The Neurobiology of Sleep: Genetics,
Cellular Physiology and Subcortical Networks. Nat Rev
Neurosci, 2002; 3: 591
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