Segmental structure of the EEG alpha activity in adolescents with schizophrenia-spectrum disorders

Lomonosov Moscow State University, Moskva, Moscow, Russia
Zhurnal vysshei nervnoi deiatelnosti imeni I P Pavlova (Impact Factor: 0.11). 05/2005; 55(3):329-35.
Source: PubMed


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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    • "As compared to group I, the magnitude of the peaks is reduced and the peaks themselves are shifted to lower frequencies. These results are in agreement with prior results reported by Borisov et al. [8], where the dampening of α-activity and amplification of low-frequency δ-and θ-activity is considered as a diagnostic sign of schizophrenia. The scale of fluctuations in the difference moment is increased compared to the group I case (Fig. 4b). "
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