EFFECTS OF DISTURBING AUDITORY NOISE ON THE COMPLEXITY OF ELECTROCORTICAL ACTIVITY

Abstract

The effects of disturbing noise on the nonlinear electrical brain (EEG) dynamics were investigated in a sample of 12 healthy volunteers. The prediction that a high intensity noise increases the dimensional complexity of brain activity as compared to a low intensity noise, was confirmed using a deterministic chaos algorithm. Further, there was a tendency for rest conditions to have a higher dimensional complexity than the condition in which the low-intensity noise was presented. Although a Fourier-analysis of the EEG revealed a difference in the alpha power between the rest condition at the end of the experiment and the noise conditions, no effect of noise intensity on the EEG power spectrum was obtained. The data indicate that the disturbing effect of a loud noise results in the recruitment of additional cortical networks and thus increases the complexity of cortical cell assemblies.