The cyclic alternating pattern sequences in the dynamic organization of sleep.

The cyclic alternating pattern (CAP) is a physiological component of normal NREM sleep, functionally correlated with long-lasting arousal oscillations. This EEG periodic activity, organized in sequences of two or more decasecond cycles, is detectable also in coma and in other neurologic disorders, appearing as a general modality of arousal organization. Within NREM sleep, the fluctuations of CAP alternate with sustained homogeneous EEG patterns, characterized by a greater stability of arousal and called non-CAP (NCAP). In 20 sleep records of 10 healthy young adults we analysed the chronological relationship between CAP and 3 fundamental states of arousal: wakefulness, NREM sleep, REM sleep. Sleep onset and sleep recoveries after nocturnal awakenings were closely linked to CAP sequences, indicating a functional linkage between cyclic fluctuations of arousal and the beginning of any sleep behavioural state. On the basis of their temporal relationship with CAP sequences, the waking to sleep and the waking transitions appeared a symmetrical events in the organization of arousal, whereas the NREM to REM transitions and the REM to NREM transitions occurred as asymmetrical events. Moreover, almost 50% of all NREM stage changes were accompanied by CAP sequences. The EEG and dynamic features of CAP sequences show morphological and behavioural analogies with some phasic phenomena (i.e., phase d'activation transitoire or micro-arousals) and EEG patterns reported in the literature (e.g., tracé alternant; phase transitionnelles; tracé intermittent). Our data suggest a functional correlation between the control mechanisms of CAP and the organization of sleep.

[1]  B. Evans.  Cyclic EEG changes in subacute spongiform and anoxic encephalopathy. , 1975, Electroencephalography and clinical neurophysiology.

[2]  A. Loomis,et al.  Cerebral states during sleep, as studied by human brain potentials , 1937 .

[3]  B. Schwartz,et al.  Indicateur de l'tat de prsence et tracs lectroencphalographiques dans le sommeil nembutalique? , 1959 .

[4]  A. Rechtschaffen,et al.  A manual of standardized terminology, technique and scoring system for sleep stages of human subjects , 1968 .

[5]  M. Steriade,et al.  Slow rhythmic oscillations of EEG slow-wave amplitudes and their relations to midbrain reticular discharge , 1983, Brain Research.

[6]  Alfred L. Loomis,et al.  DISTRIBUTION OF DISTURBANCE-PATTERNS IN THE HUMAN ELECTROENCEPHALOGRAM, WITH SPECIAL REFERENCE TO SLEEP , 1938 .

[7]  M. Escande,et al.  Apport d'une nouvelle methode d'analyse graphique a l'etude de l'organisation du stade II du sommeil de l'homme , 1981 .

[8]  W. Dement,et al.  Cyclic variations in EEG during sleep and their relation to eye movements, body motility, and dreaming. , 1957, Electroencephalography and clinical neurophysiology.

[9]  R. Thom.  Stabilité structurelle et morphogenèse , 1974 .

[10]  P. Davis,et al.  HUMAN BRAIN POTENTIALS DURING THE ONSET OF SLEEP , 1938 .

[11]  M. Terzano,et al.  Morphologic and functional features of cyclic alternating pattern (CAP) sequences in normal NREM sleep. , 1986, Functional neurology.

[12]  B. Roth,et al.  The clinical and theoretical importance of EEG rhythms corresponding to states of lowered vigilance. , 1961, Electroencephalography and clinical neurophysiology.

[13]  J. Pilcher,et al.  Automatic analysis overcomes limitations of sleep stage scoring. , 1986, Electroencephalography and clinical neurophysiology.

[14]  D Mancia,et al.  Is the EEG cyclic alternating pattern a true autonomous entity? Analytic study in a case of post-traumatic coma with good prognosis. , 1982, European neurology.

[15]  L. Johnson,et al.  Evoked K-complexes and cardiovascular responses to spindle-synchronous and spindle-asynchronous stimulus clicks during NREM sleep. , 1978, Electroencephalography and clinical neurophysiology.

[16]  M. Steriade,et al.  Slow rhythmic rate fluctuations of cat midbrain reticular neurons in synchronized sleep and waking , 1982, Brain Research.

[17]  M. Terzano,et al.  Periodic activities in Creutzfeldt-Jakob disease and epilepsy. , 1983, Progress in clinical and biological research.

[18]  Francis A. Echlin.  Book reviewObnubilations, comas et stupeurs Études électroencéphalographiques: H. Fischgold and P. MathisElectroenceph. clin. Neurophysiol., Suppl. No. 11, Masson et Cie, Paris, 1959, 126 pp. $ 8.00 , 1961 .

[19]  F. Calbucci,et al.  Correlations between intracranial pressure and EEG during coma and sleep. , 1981, Electroencephalography and clinical neurophysiology.

[20]  E. Lugaresi,et al.  Some periodic phenomena arising during drowsiness and sleep in man. , 1972, Electroencephalography and clinical neurophysiology.

[21]  O. Benoit,et al.  Individualisation d'un sommeil ondes lentes et activit phasique , 1967 .

[22]  M. Terzano,et al.  The cyclic alternating pattern as a physiologic component of normal NREM sleep. , 1985, Sleep.