Music structure determines heart rate variability of singers

Area of Science:

• Music Psychology
• Cardiovascular Physiology
• Respiratory Science

Background:

• Choir singing is linked to enhanced wellbeing, potentially due to altered respiration patterns affecting heart activity.
• Respiratory sinus arrhythmia (RSA), the coupling of heart rate variability (HRV) to respiration, has soothing effects and benefits cardiovascular function.
• RSA is more pronounced during slow breathing (≤0.1 Hz), a characteristic of singing.

Purpose of the Study:

• To investigate the impact of singing, as a form of guided breathing, on HRV and RSA.
• To compare the effects of different singing structures on physiological responses.
• To explore the connection between song structure, respiration, and heart rate.

Main Methods:

• Healthy 18-year-olds participated in three singing tasks: humming, singing a hymn with free breathing, and singing a slow mantra with controlled breathing.
• Continuous heart rate (HR) measurement was performed during the tasks.
• A case study involved advanced monitoring (HR, respiration, skin conductance, finger temperature) during singing tasks.

Main Results:

• Unison singing of regular song structures led to simultaneous acceleration and deceleration of singers' heart rates.
• Singing tasks demonstrated a connection between song structure, respiration patterns, and heart rate dynamics.
• The study identified how guided breathing in singing influences HRV and RSA.

Conclusions:

• Singing, particularly with regular structures, induces a synchronized heart rhythm among singers, termed 'inner entrainment'.
• This physiological synchronization may contribute to the subjective wellbeing associated with singing.
• Further research is needed to understand how this inner entrainment affects perception and behavior.