Autor: N. F. Podvigin, E. V. Boikova, N. B. Kiseleva, E. Poppel, T. V. Bagaeva
Rok vydání: 2002
Předmět:
Zdroj: Journal of Evolutionary Biochemistry and Physiology. 38:468-474
ISSN: 0022-0930
DOI: 10.1023/a:1021162105735
Popis: There were studied characteristics of gamma-oscillations in responses of neurons of the lateral geniculate body (LGB) in cat to exposure in their receptive fields (RF) of half-tone and binary test images. The gamma-oscillations were observed in 38.8% of cases (69 cells). The spectral characteristics (SC) (the band 20–100 Hz) of the neuronal responses to adequate stimuli (on- and off-responses correspondingly of on- and off-neurons) were analyzed. The total of 5930 poststimulus histograms (PSTH) of responses constructed from 177 900 neuronal impulse responses were considered. The mean value of the SC dominant frequencies of the whole sample of the neuronal responses amounted to 44.74 ± 21.46 Hz. In this cell sample, the neurons were revealed, which generated oscillations with markedly different frequencies in response to the same stimuli. Based on this property, three types of neurons were determined, with the mean oscillation frequencies of 26.95 ± 4.35, 52.02 ± 9.05, and 85.79 ± 7.19 Hz. The histograms of distribution of peak frequency values in SC of the neuronal responses and of index values of these oscillation peaks also revealed three maxima that corresponded to the frequencies of the three described types of neurons. The mean values of dominant frequencies of gamma-oscillations in responses of all three types of neurons remained constant (within the limits of dispersion) at changes of spatial-brightness parameters of test stimuli as well as at changes of the neuronal excitation level (the number of impulses in responses). The oscillation index values of dominant frequencies depended on parameters of the test images and correlated with the neuronal excitation level (the coefficient of correlation was 0.78 from data of 5930 CX). The suggestion is made about the existence in the neuronal network of the synchronization mechanisms functioning on the principle of “multiple synchronization. ”
Databáze: OpenAIRE