Biomaterial Database

All-night sleep EEG and artificial stochastic control signals have similar correlation dimensions. 1994

P Achermann, and R Hartmann, and A Gunzinger, and W Guggenbühl, and A A Borbély

Institute of Pharmacology, University of Zurich, Switzerland.

EEG signals have been considered to be generated either by stochastic processes or by non-linear deterministic systems exhibiting chaotic behavior. To address this problem, the correlation dimension of the EEG was computed and compared to the correlation dimension of an artificial signal with identical power spectrum. By using a new type of personal super computer we were able for the first time to calculate the correlation dimension for the sleep episode of an entire night as well as for the corresponding artificial signal. The correlation dimension was high in episodes of rapid eye movement (REM) sleep, declined progressively within each non-REM sleep episode, and reached a low level at times when EEG slow waves (0.75-4.5 Hz) were dominant. The correlation dimension of the artificial signal and the EEG changed largely in parallel, although on average the values of the artificial signal were 7.3% higher. These results do not support the hypothesis that the sleep EEG is generated by a chaotic attractor.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D004569	Electroencephalography	Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.	EEG,Electroencephalogram,Electroencephalograms
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D012890	Sleep	A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility.	Sleep Habits,Sleeping Habit,Sleeping Habits,Habit, Sleep,Habit, Sleeping,Habits, Sleep,Habits, Sleeping,Sleep Habit
D012894	Sleep Stages	Periods of sleep manifested by changes in EEG activity and certain behavioral correlates; they formerly included Stage 1: sleep onset, drowsy sleep; Stage 2: light sleep; Stages 3 and 4: delta sleep, light sleep, deep sleep, telencephalic sleep. In 2007, sleep stages were redefined by The American Academy of Sleep Medicine (AASM) as: N1-N2 (sleep onset - light sleep), N3 (SLOW-WAVE SLEEP), and REM SLEEP.	N1-Sleep,N2-Sleep,NREM Stage 1,NREM Stage 2,N1 Sleep,N2 Sleep,Sleep Stage,Stage, Sleep,Stages, Sleep
D013269	Stochastic Processes	Processes that incorporate some element of randomness, used particularly to refer to a time series of random variables.	Process, Stochastic,Stochastic Process,Processes, Stochastic