An Approach to Analysis of EEGs Recorded During Music Listening

Abstract

In this paper, we propose and examine methods for analyzing EEG (Electroencephalogram) in particular during music listening. The relationship between EEG and music cognition is also discussed. Music can be regarded as input to the brain system which influences the human mentality along with time. Since music cognition has many emotional aspects, it is expected that EEGs recorded during music listening may reflect the electrical activities of brain regions related to those emotional aspects. The brain system consists of dozens of functional subsystems and we are in agreement with the hypothesis that their cooperative process enables high level recognition such as music listening. From the point of view of informational neurobiology, the spatial and temporal frequency pattern was extracted from EEG. First, the autoregressive model was applied to the power spectrums of EEGs of different brain regions. Then, the frequency structures were compared using a statistical model. We focused on change of frequency and spatial pattern of the brain's activated area in response to the music structure. Several observations show that there was a sudden drop in the frequency's average at the beginning of recapitulation and a difference in activated areas between relaxing and music listening conditions. We also calculate the information flow between EEG channels by directional coherence analysis. The experimental results showed that information flow pattern also respond to the music structure and this was thought to be peculiar to the cognitive process. In conclusion, our methods were more precise and easier to use in understanding brain activity than the conventional one. The results reflect the level of consciousness and the brain's activated area during music listening. It is anticipated that this approach will provide a new perspective on cognitive musicology.