Emotions from musical notes? A psycho-acoustic exploration with Indian classical music

The most interesting feature of Indian Classical Music is the existence of Raagas. Each Raaga has its own peculiar ascending and descending movement called the Arohana and Avarohana. Even if two (or more) Raagas are made up of the same notes, the combinational varieties of notes evoke different emotions. In this work, we envisage to study how emotion perception in listeners' changes when there is an alteration of merely a single note in a pentatonic Raaga and also when a particular note(s) is replaced by its flat/sharp counterpart. 30-s recordings were done for two pair of Raagas which were chosen in a manner such that they are having difference in only one note keeping all others same. The fractal dimension of the auditory waveform provides a robust nonlinear quantitative parameter with which the two pair of audio clips can be compared. Also, the emotional appraisal from these two pairs were assessed on the basis of psychological listening tests as well as from cognitive response in the form of EEG experiments done on 10 participants. Interesting new results are obtained on how a trivial change in the note structure of a particular Raaga influences human emotion to a large extent.