You've probably felt the increase in your heart rate listening to a fiery punk song or the relaxation induced by a slow ballad. But Italian researchers just completed a study suggesting music has more ways to affect us than just by tempo.

For the study, which appeared in the journal Circulation, the scientists strapped electrocardiograms onto 24 subjects and made them listen to five different selections of classical music. Meanwhile, the team monitored their blood pressure, breathing and blood vessel constriction.

Beethoven had an fascinating effect on the subjects' homeostases. Crescendos-those slow, dramatic swellings of intensity-led to increases in heart rate, blood pressure and breathing, but those effects dissipated during pauses, or rests.

In effect, lead researcher Luciano Bernardi said, our bodies are a little like sheet music: our respiratory and cardiovascular systems follow the ups and downs of the music we are listening to. This could give music therapy a new boost in the clinical arena.

For example, if you wanted someone to maintain a steady heart rate, you could have them listen to music with phrases that are about 10 seconds long, which the researchers said synchronizes with our natural cardiovascular rhythm.

Of course, it could just be that the participants in this study were all Beethoven aficionados, so the music-homeostasis connection requires more study. But the findings further our knowledge of why music therapy has proven so effective and why music affects people, or at least their hearts, so deeply.