Music Keeps Rhythm for Heart and Lungs
By Crystal Phend, Staff Writer | MedPage Today | Published: June 22, 2009 | Reviewed by Zalman S. Agus, MD; Emeritus Professor, University of Pennsylvania School of Medicine and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
Explain to interested patients that music is known to impact blood pressure and stress levels in particular.
Note that the study revealed similar synchrony between musical amplitude and cardiovascular variables regardless of musical training or reported emotional response.
SAN FRANCISCO, June 22 — Cardiovascular and breathing rates consistently fall into step with musical crescendos and rhythms, according to a controlled clinical trial that may give impetus to new musical therapies.
Contrary to the conventional view of music as an intensely personal medium, researchers found that the same piece of music had similar cardiovascular effects on all subjects.
Taking advantage of these interactions may open the way to standardized treatments for blood pressure control and rehabilitation, Luciano Bernardi, MD, of Pavia University in Pavia, Italy, and colleagues wrote in the June 30 issue of Circulation.
However, Joep Perk, MD, of Oskarshamn District Hospital in Sweden, sounded a note of caution.
Given the small study size and inclusion of only classical music and young people, “I don’t think we can yet say the results represent strong evidence-based medicine,” he said on behalf of the European Society of Cardiology.
Since the evidence for a link between stress and cardiovascular health is strong, the best role for music may be in relaxation therapies, Dr. Perk said in a prepared statement.
Some prior studies have shown that soothing sounds, such as waves on a beach, and rhythmically homogenous music can reduce stress and lower blood pressure, respiration, and heart rate. (See Music’s Effect on Heart Patients Unclear and ASH: Daily Doses of Bach and Breathing Lower Blood Pressure)
But Dr. Bernardi’s group said it saw greater possibilities for autonomic control — to induce a desired pace rather than simply reduce it from baseline.
Their study included 24 healthy, white participants (average age 25). Half were experienced choir singers, while the rest had no prior music training.
After five minutes of baseline recordings while participants were lying down with their eyes closed and headphones on, they listened in random order to the following range of compositions:
- The well-known orchestral adagio from Beethoven’s Ninth Symphony
- The emotional and lyrical operatic aria “Nessun dorma” from Puccini’s “Turandot”
- A so-called “Intellectual” piece of solo singing from Bach, the cantata “Gott soll allein mein Herze haben” (BMW 169)
- The aria “Va pensiero” from Verdi’s opera “Nabucco”
- The drinking song “Libiam Nei Lieti Calici” from Verdi’s “La Traviata”
- Two minutes of silence
Most of the participants reported no particular emotional response to or definite preference for particular compositions. None reported strong emotions or “chills” from listening to the music.
However, there appeared to be a subconscious autonomic response.
The researchers saw consistent cardiovascular effects that dynamically corresponded to the composition both in degree and timing.
“Almost every music crescendo or emphasis induced progressive skin vasoconstriction along with increases in blood pressures and heart rate,” they wrote.
The most rapid responses were in the interval between R waves on the electrocardiogram and in the middle cerebral artery flow velocity, followed by systolic and diastolic blood pressures and skin vasomotion.
By contrast, the period of silence and baseline measurement periods were marked by only minor changes with progressive skin vasodilation and reductions in heart rate and blood pressure.
The individual musical composition with the strongest correlations to cardiovascular changes was Puccini’s “Nessun dorma,” which showed progressive arousal during the series of increasing crescendos.
The orchestral Beethoven adagio, which also includes several crescendos of progressively increasing intensity, showed significant but lesser correlations with cardiovascular variables.
The Bach cantata produced minor relaxation in participants’ cardiovascular measures, possibly because the “high but short peaks in the music envelope” were too close together to elicit responses, the researchers suggested.
The musicians and nonmusicians showed no differences in overall response.
Interestingly, despite different emotional overtones, the two Verdi arias have rhythmic “phrases” timed close to the circulatory oscillation frequency — Mayer waves of blood pressure — of six cycles per minute.
Because this 10-second period arises from the autonomic modulation of the cardiovascular system, researchers have tried to modulate it through yoga, prayers, and other methods to slow respiration.
“Va pensiero” showed peak coherence with cardiovascular responses at between 0.08 and 0.09 Hz, “the same rhythm as the musical phrase, 0.087 Hz, which indicates that while listening to the central part of the track, the subjects synchronized their Mayer waves with the rhythm of the music.”
The aria “Libiam nei lieti calici,” showed similar “entrainment” of cardiovascular variables at its 0.110 Hz frequency (9.04-second period, P<0.0001).
However, “this synchronization did not appear to be linked to respiration, which suggests an effect directly mediated by the autonomic nervous system,” Dr. Bernardi’s group said.
Respiration increased briefly in amplitude during musical crescendos with overall regularization of rhythm and a tracking in respiratory power, but not end-tidal carbon dioxide.
The researchers said these findings have “considerable implications for the use of music as a therapeutic tool.”
The main reason: despite popular belief in a personal, emotional response to music, all the participants responded similarly.
“Our findings suggest that music is sensed and processed at a subconscious level, closely mirrored by autonomic cardiovascular responses,” they concluded.
“These results have clear implications for the practice of music therapy: If music induces similar physiological effects in different subjects, standard therapeutic interventions should be possible.”
But the researchers cautioned about generalizing the findings, given the similar age, ethnic background, and education level of the study participants.
The study was supported by a grant from the Signe and Ane Gyllenberg Foundation.
The researchers reported no conflicts of interest.
Primary source: Circulation: Journal of the American Heart Association
Bernardi L, et al “Dynamic interactions between musical, cardiovascular, and cerebral rhythms in humans” Circulation 2009; 119.