Il ruolo della microstruttura del sonno nell'attivazione delle anomalie intercritiche in epilessia

Epileptic EEG discharges are modulated by the ongoing state of vigilance (i.e. activation during Non-REM sleep and during conditions of arousal instability). The EEG translation of unstable sleep is expressed by the cyclic alternating pattern (CAP), a 20-40s biphasic periodic activity composed of transient arousals (phase A) separated by intervals of background activity (phase B). In Primary Generalized Epilepsy and in Focal Lesional Epilepsy, interictal EEG abnormalities are triggered by phase A, whereas Benign Rolandic Interictal Spikes are poorly modulated by CAP components. These different behaviors seem to rely on the linkages between the epileptogenic focus and the CAP-related circuitry. In this relationship, a critical role could to be played by the thalamo-cortical loops centered on the Nucleus Reticularis Thalami, which is able to generate CAP cycles and to activate interictal spikes.