Temporal changes in electroencephalographic power spectrum on passive listening to three selected melodic scales of Indian music on healthy young individuals - a randomized controlled trial

Abstract

Music is said to affect the brain in different ways. To the best of our knowledge, research works on the effect of passive listening to different melodic scales of Indian music on Electroencephalogram (EEG) power spectrum is rare to find. In this randomized control trial, 137 healthy subjects were randomly divided into 4 groups (A to D, n~32 in each group), of which A (raga Ahir Bhairav), B (raga Kaunsi Kanada), C (raga Bhimpalas) received music intervention while group D was the control arm. Nineteen channel scalp EEG was recorded for 30 minutes [10 min for each condition, before (BI), during (DI) and after intervention (AI)] and conducted power spectral analysis of waveforms in standard frequency bands. Two-way ANOVA was performed across conditions and groups, to determine the scalp regions showing significant changes, for each frequency band separately. Across conditions, significant change in BI alpha and AI theta, beta1, beta2 bands, while between groups, group B had significant change in alpha and group C in beta1 power, mostly involving frontal regions was seen. Mid Frontal PSA exhibited an increased theta power in group C and D (AI), while alpha and beta1 power increased in group B and C (in group C, beta2 increased significantly). Temporal trend analysis (2-minute segments), showed that there was a significant fall in frontal alpha DI in group B; while in A, C and D groups, the drop seen BI reduced DI and AI. Similarly, the beta1 drop reduced DI and AI in group C and D, while it increased in group B (DI) and group A (AI). Music caused relaxation effect with scales B and C causing maximal effect. In line with existing literature, it may be concluded that listening to these melodic scales was associated with mind wandering effect and probable visual imagery/recall.