Centrotemporal spikes during NREM sleep: The promoting action of thalamus revealed by simultaneous EEG and fMRI coregistration☆

Benign childhood epilepsy with centrotemporal spikes (BECTS) has been investigated through EEG-fMRI with the aim of localizing the generators of the epileptic activity, revealing, in most cases, the activation of the sensory-motor cortex ipsilateral to the centrotemporal spikes (CTS). In this case report, we investigated the brain circuits hemodynamically involved by CTS recorded during wakefulness and sleep in one boy with CTS and a language disorder but without epilepsy. For this purpose, the patient underwent EEG-fMRI coregistration. During the "awake session", fMRI analysis of right-sided CTS showed increments of BOLD signal in the bilateral sensory-motor cortex. During the "sleep session", BOLD increments related to right-sided CTS were observed in a widespread bilateral cortical-subcortical network involving the thalamus, basal ganglia, sensory-motor cortex, perisylvian cortex, and cerebellum. In this patient, who fulfilled neither the diagnostic criteria for BECTS nor that for electrical status epilepticus in sleep (ESES), the transition from wakefulness to sleep was related to the involvement of a widespread cortical-subcortical network related to CTS. In particular, the involvement of a thalamic-perisylvian neural network similar to the one previously observed in patients with ESES suggests a common sleep-related network dysfunction even in cases with milder phenotypes without seizures. This finding, if confirmed in a larger cohort of patients, could have relevant therapeutic implication.