[Segmental structure of the EEG alpha activity in adolescents with disorders of schizophrenic spectrum].

Zhurnal vysshei nervnoi deiatelnosti imeni I P Pavlova (Impact Factor: 0.21). 01/2005; 55(3):329-35.
Source: PubMed

ABSTRACT The EEG records of 39 healthy adolescents and 45 age-matched schizophrenic patients were analyzed. The broad-band EEG spectral analysis and segmental analysis of the alpha-activity revealed significant differences between the groups. Schizophrenics differed in a decreased spectral power for the alpha2 and betal frequency bands and increased power for the delta and theta bands. Also, in schizophrenic adolescents, quasi-stationary alpha-rhythm segments were longer, and within-segmental EEG amplitudes were higher than in the healthy subjects; the amplitude variability and the steepness of transitions between neighbor segments were increased. The results of the EEG segmental analysis suggest a disintegration of local cortical neuronal ensembles in schizophrenia.

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