Perception of Devotion and Happiness in Indian Spiritual Music: An Acoustical and Audience Response Exploration

Since the age of the Vedas, devotion has remained a key component of Indian music through centuries of changes and foreign influences. The brightest example of this is the Bhakti tradition, a Pan-Indian movement (Seventh–Twentieth Century CE), which integrated poetry and music in the transmission of spiritual and social goals. Earlier studies on a few European spiritual music traditions indicate their great impact on the human mind, brain, and body, but such studies in the Indian context are rare. This paper aims to study the acoustical and perceptual correlates of two Indian spiritual music traditions, (a) Sikh Gurbani/ Sabad Kirtan and (b) Bangla Vaishnav Kirtan, both of which emerged from the Bhakti tradition. Taking the recordings of 25 songs from each tradition, the acoustical time series of these music clips were analysed using different linear (pitch and intensity contours, spectral centroid, entropy, etc.) and nonlinear (Detrended Fluctuation Analysis) techniques. Results revealed that these songs range from simple to complex structures, but for both traditions, underlying repetitive patterns in the lyrics, melody, and rhythm are the key commonality. Next, taking multiple 30-s segments from 6 songs of these two spiritual traditions and 6 songs of non-spiritual genres from the same two cultures, emotion responses were collected in a 5-point Likert scale with 13 “emotion-words” from 348 participants of various age groups, genders, and socio-cultural and linguistic backgrounds. Results of the audience response survey revealed the dominance of devotion perception while listening to the songs of both traditions, with a significant co-elicitation of happiness in Bangla Kirtans and more prominent co-elicitations of awe and calmness for Sabad Kirtans. Average emotion arousal in females was higher than in male participants except for devotion and understanding the lyrical meaning of the songs contributed to a higher intensity of devotion perception. This is a pilot scientific study on the acoustical and perceptual attributes of two Indian spiritual music traditions and the unique findings are expected to open new pathways for future research regarding their applicational aspects.