Listen to the Inner Self

Heart rate is regulated by the autonomic nervous system (ANS), producing a natural heart rate rhythm. When we are under chronic stress, the ANS activates the ‘fight-or-flight’ response constantly, which reduces the variability in our heart rate. On the contrary, greater flexibility in heart rhythm can be observed when we are relaxed. The more flexible the heart rhythm is, the more capable we are of dealing with everyday stressors. Heart-Rhyme is an exploration on a real-time sonification of heart rate variability. It transforms the heartbeat rhythm into a musical rhythm for biofeedback purpose.

Following the idea of ‘natural coupling’, we try to present the timing variations of heartbeat data with the timing variations in sounds instead of timbre, pitch or other acoustic properties. The rhythm of music describes a specific temporal pattern of sounds. It is about the variations in the arrangement of sounds through time. Therefore, we focus on presenting the heart rate data with the rhythmical changes in a short chord. We assume the natural coupling between the heart rate variations and the rhythmical changes can be perceived by naturally and intuitively.

The heart rate variability can be represented by the variations of rhythm in MIDI notes. Here, we proposed four promising audio-forms:

1. arpeggio chords with speed variation

Th audio-form 1 presents the heartbeat intervals by changing the intervals between three notes of a chord. It is the most direct mapping between timing variations of heartbeats and the sounds.


2. arpeggio chords with emphasis variation

In the audio-form 2, the emphasis of a G chord arpeggio is being modulated among four notes according to the latest heartbeat interval data.


3. two distinct notes with inter-beat interval delay

4. two stereophonic notes with inter-beat interval delay

Th audio-forms 3 and 4 use the interval between two successive notes to present the most recent heartbeat interval data. In these two forms, the differential of the heartbeat interval data is presented as sound.


Yu, B., Feijs, L., Funk, M., & Hu, J.Designing Auditory Display of Heart Rate Variability in Biofeedback Context  In 21th International Conference on Auditory Displays (ICAD 2015), Graz, Austria, July 2015