Cyclic Alternating Pattern and Sleep

Publisher Summary The variations of the arousal level across the 24 hour rhythm play an important role in the modulation of epileptic events. The sleep–wake cycle, and particularly the conditions of instability that occur during sleep, affect the appearance of interictal electroencephalography discharges and epileptic seizures significantly. An important modulation of the sleep–wake rhythm is mediated by the endogenous circadian system. Both human and animal studies have demonstrated that the mammalian circadian oscillator is located in the suprachiasmatic nuclei of the anterior hypothalamus and serves as a topical source for the timing boundaries of sleep and wakefulness in the 24 hour cycle. The variations of sleep propensity over time are not only affected by the biological clock but are also influenced by the subject's prior sleep–wake history. Experimental investigation has ascertained that the intrinsic alternation between non-rapid eye movement and rapid eye movement sleep is under the control of an oscillatory process generated by a particular rhythmicity of neurotransmission and by the reciprocal interaction between two neuronal groups. The variations of the arousal level across the 24 hour rhythm play an important role in the modulation of epileptic events.