Effect of Selected Music Soundtracks on Cardiac Vagal Control and Complexity Assessed by Heart Rate Variability

Area of Science:

• Physiology
• Music Therapy
• Psychology

Background:

• Music listening is linked to stress reduction, but its therapeutic application, especially passive music therapy, remains debated.
• Understanding the physiological impact of specific music frequencies on the human organism is crucial for its therapeutic integration.

Purpose of the Study:

• To investigate the effects of passive, vocal-free music therapy frequencies on cardio-vagal and complexity indices of short-term heart rate variability (HRV) in healthy young adults.
• To assess the potential of music therapy to induce a calming effect by analyzing physiological and subjective responses.

Main Methods:

• Thirty healthy young adults (15 male, mean age 19.7 years) underwent a protocol including baseline silence and exposure to three distinct music frequency ranges (20-1000 Hz, 250-2000 Hz, 1000-16000 Hz) interspersed with silence.
• Heart rate variability (HRV) parameters were evaluated in time, spectral, and geometrical domains to assess cardio-vagal and emotional regulation.
• HRV complexity was quantified using approximate entropy and sample entropy (SampEn), with subjective pleasantness rated on a Likert scale.

Main Results:

• Music exposure, particularly higher frequencies (Music 3: 1000-16000 Hz), led to significantly increased RR intervals and SampEn compared to silence.
• A higher geometrical cardio-vagal index was observed during Music 2 (250-2000 Hz) compared to its corresponding silence phase.
• Subjective ratings indicated that music phases were perceived as significantly more pleasant than silence phases across all comparisons.

Conclusions:

• The study suggests that passive music therapy, especially with higher frequencies, positively influences cardio-vagal modulation and HRV complexity.
• Findings indicate a potential relaxing effect of specific music frequencies on the human organism, supporting its use as a complementary therapy.
• The combination of physiological and subjective data supports the efficacy of music therapy in promoting relaxation and well-being.