Fractal Features of the Background Activity of the Neurons in the Auditory Center of the Frog Midbrain
The statistical characteristics of the background impulse activity recorded in some neurons of the auditory center of the midbrain (semicircular torus) of the common frog were studied. The methods used in the analysis of the temporal f low of fractal point processes were used. Most neurons in the range of time intervals from hundreds of milliseconds to several tens of seconds experienced a power increase in the ratio of the dispersion of the number of pulses to the average value of this number (Fano factor), although cells were also observed whose background impulsation was close to random. The method based on the registration of local features (the dependence of the Allan factor on the same interval) confirmed the presence of fractal properties in many cells. Usually, the power growth of this factor began at large time intervals. The third method of fractal analysis used (the Hurst index) also argued in favor of the randomness and fractality of the background firing process. The analysis of the relationship of these fractal characteristics with other parameters used to describe the statistics of random point processes was provided. Comparison with the data obtained on the neurons of the medulla oblongata indicates a slight increase in the variability of this activity along the auditory pathway.