Air Date: Week of January 2, 2004

Living on Earth’s Cynthia Graber reports on research showing that extremely low sound vibrations called infrasound may lead to strange emotional and physical responses.

Transcript

CURWOOD: Coming up: the promise and perils of digging for natural gas in the Peruvian Amazon. First, this note on emerging science from Cynthia Graber.

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GRABER: An odd feeling in the pit of your stomach. A sense that someone is watching you. Chills down your spine. Scientists say these often-inexplicable emotions might that e explained by infrasound.

Infrasound is extremely low frequency sound played at levels most human can’t hear. To test the effects of infrasound on humans, a team of scientists in England used a pipe to create a twenty-hertz tone. Then, they reproduced the tone during a concert, mixing it in and out of the contemporary music being played on stage. Almost a quarter of the 750 people in the audience reported strange feelings during the pieces that included infrasound, such as a sensation of sorrow or fear, or getting chills.

Scientists don’t know exactly how infrasound causes these responses. The psychologist on the team says emotional responses might occur when the brain tries to interpret low frequency sounds. Volcanoes and earthquakes, for example, make infrasound when active. But to understand why some people have physical responses, such as feeling hot or cold sensations, the researchers have invited a physiologist to join the continuing study.

That’s this week’s Note on Emerging Science. I’m Cynthia Graber.

CURWOOD: And you're listening to Living on Earth.

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