Frequency dependent emotional responses to sound: A cross-modal analysis of electroencephalogram band power and emotion perception

Abstract

Enabling machines to comprehend human emotions serves as the motivating factor for our research. This effort significantly contributes to advancing emotion recognition and human-computer interaction. Our study explores the fundamental associations between emotional responses and auditory characteristics, with a primary focus on frequency. To achieve this, we conducted a two-stage perception test, aiming to identify the interplay between EEG band power and dominant emotion class as a function of frequency. Musical notes, ranging between 110 Hz and 973 Hz, served as our stimuli. During the first stage, we collected participants' EEG data, categorized it into distinct energy bands (Alpha (α), Beta (β), Delta (δ), Theta (θ), and Gamma (γ)), and analyzed band power and ratios. In the subsequent stage, we had participants evaluate their emotional responses to each stimulus. Our results from this two-stage perception test suggest that an increased tangent of the α / β band power ratio corresponds to Low-Arousal emotions, while a diminishing tangent correlates with High-Arousal emotions. Furthermore, we observed a crossover point for four primary emotions within the 417–440 Hz frequency range. This finding supports the hypothesis that the 432–440 Hz range is emotionally neutral.