Massage therapists know that a session set to the sound of Peter Kater or George Skaroulis will effect better healing than one set to the Deftones or Rage Against the Machine—but the “why” of this isn’t completely understood.

Now, a UCLA-based team of researchers has isolated some of the ways in which distorted and jarring music is so evocative, and they believe that the mechanisms are closely related to distress calls in animals.

“Music that shares aural characteristics with the vocalizations of distressed animals captures human attention and is uniquely arousing,” said Daniel Blumstein, one of the study’s authors and chair of the UCLA Department of Ecology and Evolutionary Biology.

In the control condition, the music was generic and emotionally neutral, without noise or abrupt transitions in frequency or pitch, according to a UCLA press release. Bryant likened it to rather plain elevator music.

Another condition began in an easy-listening manner but then suddenly broke into distortion, much like Hendrix famously did at Woodstock.

(For an example of each of these conditions, visit

Undergraduate students were asked to listen to an example of each condition and then rate the examples based on two factors: how arousing they found the music and whether the emotional feeling in the music was positive (such as happy) or negative (such as fear-inducing or sad), the press release note. No subject heard more than one example from any condition.

When the music featured distortion, subjects rated it as more exciting than the compositions without distortion. They also were more likely to describe the music as charged with negative emotion.

The researchers believe the effect of listening to music with distortion is similar to hearing the cries of animals in distress, a condition that distorts animals’ voices by forcing a large amount of air rapidly through the voice box, according to the press release.

“This study helps explain why the distortion of rock ‘n’ roll gets people excited: It brings out the animal in us,” said Bryant.

Editor’s note: Read “Vibrational Healing: The Therapeutic Use of Sound and Music,” by Acutonics’ Ellen F. Franklin, in MASSAGE Magazine‘s July issue.

Related articles:

Are Humans Wired to Appreciate Music?

Music’s Healing Potential Studied