The effect of a rhythmic pulse on the heart rate: Little evidence for rhythmical ‘entrainment’ and ‘synchronization’

Abstract

In this study, we investigate the influence of musical tempo on the heart rate. Previous studies showed ambiguous results. Two effects are considered: first, an adaption of the heart rate frequency to the tempo of a musical stimulus (‘entrainment’) and second, the phase synchronization between the stimulus-onset and the R-waves in the ECG (‘synchronization’). A regulatory feedback loop was programmed, which constantly measured the actual heart rate. A simple Djembé-beat was used as a musical stimulus and coupled to the actual heart rate in real-time. To test for ‘entrainment’ effects, we adapted the tempo of the stimulus in real-time to the actual heart rate by increasing the rate 25%, 40% or 55% over the baseline tempo. To test for ‘synchronization’ effects, we presented the stimulus in a constant tempo, tracking the actual heart rate of the test person. Based on circular statistics, results showed no evidence for ‘entrainment’ or ‘synchronization’ effects of the stimulus on the heart rate. Overall, reactions to the trigger pulse were characterized by a high degree of interindividual differences. Thus, we conclude that there is no direct and simple correlation between the musical tempo and the HR contrary to what is often suggested in everyday psychology.

Audio-visual concert performances synchronize an audience’s heart rates

“…In other words, musical rhythms aligned with neither audiences' breathing cycles nor their heartbeat cycles. Although this lack of phase synchrony was expected for heart rhythms [40][41][42] , this contrasts previous findings that breathing aligns with musical beats 38,39 . There are a few potential reasons for this discrepancy between results.…”

“…In the phase domain, some research indicates that the alignments of breathing/heartbeats to external rhythms aid the processing of upcoming stimulus events 36,37 . In music, respiration has been shown to entrain to musical beats 38,39 , while heartbeats do not [40][41][42] . Thus, the current study aimed to further assess cardiorespiratory synchrony as an index of engagement in response to music performances in a concert audience.…”

Assessing real-world music listening in concerts

“…SRPC of both heart and respiration cycles was not significant. This was expected for the heart rhythms, as previous work showed that the heartbeat does not align with external beats (Ellis & Thayer, 2010;Koelsch & Jäncke, 2015;Mütze et al, 2020). However, this was unexpected for respiration, as previous studies found that breathing aligns with musical beats (Etzel et al, 2006;Haas et al, 1986).…”

“…One way is to calculate the coherence between oscillatory responses and actual note onsets. Although studies have shown that respiration aligns to musical beats (Etzel et al, 2006;Haas et al, 1986), there is limited evidence that heartbeats do the same (Ellis & Thayer, 2010;Koelsch & Jäncke, 2015;Mütze et al, 2020). However, this former approach assumes that oscillatory responses can occur at the frequency range of a stimulus.…”

“…For the phase domain, this would refer to whether heartbeats/ breaths align to rhythms of a stimulus. So far studies have shown that respiration entrains to musical beats (Etzel et al, 2006;Haas et al, 1986), but there is limited evidence that heart beats do the same (Ellis & Thayer, 2010;Koelsch & Jäncke, 2015;Mütze et al, 2020). A related approach to observe music-related responses is to assess synchrony across multiple participant responses that are time-locked to a stimulus.…”