THE RELATIONSHIP BETWEEN SLEEP AND EPILEPSY IN FRONTAL AND TEMPORAL-LOBE EPILEPSIES - PRACTICAL AND PHYSIOPATHOLOGICAL CONSIDERATIONS

Purpose: The influence of sleep on the incidence of seizures and the r eciprocal effects of epilepsy on sleep were analyzed in 30 patients wi th intractable partial seizures, all candidates fur surgery. Methods: The patients were classified into two groups of 15 patients according to the documented site of the epileptogenic zone: frontal lobe epileps y (FLE) and medial temporal lobe epilepsy (TLE). Frequency and waking- sleep distribution of seizures were evaluated by continuous video-EEG monitoring for 5 days, under defined antiepileptic drug (AED), sleep, and sleep deprivation regimens. Sleep organization was analyzed by pol ysomnography prior to the presurgical protocol. Results: Significant d ifferences were found between the two groups in sleeping-waking distri bution of seizures under varied conditions, and in the quality of slee p organization. In FLE patients, seizures most often occurred during s leep, although sleep organization was normal. in TLE patients, most se izures occurred while patients were awake, and sleep organization was characterized by a low efficiency index. The difference in seizure dis tribution between FLE and TLE persisted under all conditions investiga ted, i,e., after AED discontinuation and sleep deprivation. Conclusion s: Sleep recording may be useful for diagnosis of FLE, and monitoring after sleep deprivation for that of TLE, We speculate that sleep-relat ed seizures in FLE may depend on Interaction between frontal lobe area s with the thalamus cortical synchronization system and the acetylchol ine regulatory system of waking.