Modulation of the interictal epileptiform EEG activity during sleep: from oscillations to complex dynamics.
Polygraphic sleep recordings (EEG, EMG, and EOG) were performed in two groups of epileptic subjects, six with fragile-X syndrome and six with symptomatic epilepsy. Recordings were visually scored for sleep stages and number of spikes/min. Subjects with fragile-X syndrome showed a well defined pattern of production of interictal epileptiform activity with the lowest values during REM sleep; symptomatic epileptic subjects showed less defined and more variable spike/min diagrams. The spectral analysis of the outline of such diagrams confirmed these differences showing shorter periodicities (80-100 min) in the fragile-X group compared to those of the symptomatic group (160-220 min). Finally, a model with multiple feedback circuits is proposed in order to explain the different patterns observed.
Ferri
R
R
Department of Neurology, Oasi Institute for Research on Mental Retardation and Brain Aging, Troina, Italy.
Bergonzi
P
P
Elia
M
M
Ferri
P
P
Musumeci
S A
SA
D000204:Activity Cycles / Q000502:physiology; D000293:Adolescent; D002648:Child; D002940:Circadian Rhythm / Q000502:physiology; D004569:Electroencephalography; D004576:Electromyography; D004827:Epilepsy / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D005600:Fragile X Syndrome / Q000150:complications / Q000503:physiopathology; D006801:Humans; D008297:Male; D012890:Sleep / Q000502:physiology*; D013997:Time Factors