Interdependencies in the spontaneous EEG while listening to music

We studied the patterns of interdependency between different brain regions during the performance of higher cognitive functions. Our goal was to check the existence in these patterns of both task-related differences (e.g. lis tening to music vs. rest) and training-related differences (musicians vs. n on-musicians). For this purpose, a non-linear measure, called similarity in dex (S.I.), was used to detect asymmetric interdependencies between differe nt brain regions by means of EEG signals. Relatively active and passive reg ions of the brain were found where the degree of activity was represented b y excited degrees of freedom. The S.I. obtained during listening to differe nt kinds of music was compared statistically with the S.I. with eyes closed , and significant changes (P less than or equal to 0.05) were entered into schematic brain maps. A topographical representation of the S.I. yielded di fferences in the interdependency while performing different cognitive tasks . The results demonstrate the occurrence of task-related differences in bot h groups of subjects. Furthermore, subjects with musical training possessed significantly higher degrees of interdependencies than such without musica l training while listening to music but not to text We conclude that the ne w measure can be successfully applied for studying the dynamical co-operati on between cortical areas during higher cognitive functioning. (C) 2001 Els evier Science B.V. All rights reserved.