How screams shatter the brain

Distinct acoustical fingerprints of screams set the sounds apart from other types of vocalizations, a study finds.

Edvard Munch, Courtesy of the National Gallery in Oslo, Norway

July 16, 2015 at 12:00 pm

Blood-curdling screams pierce the brain. Unlike other vocalizations, screams contain an acoustical signature that alerts the brain to danger, scientists report July 16 in Current Biology. The results help explain why screams are such effective methods of communication.

By analyzing the acoustical makeup of sounds, David Poeppel of New York University and the Max Planck Institute for Empirical Aesthetics in Germany, and colleagues found that screams scored high on measures of “roughness,” a quality that comes with big swings in loudness and a very unpleasant perception. Normal speech isn’t very rough, but car and house alarms are, the researchers found. Smoothing out the rough signals in screams led people to say the screams weren’t as scary, the researchers found.

Rough screams came with more activity in the amygdala, a brain structure that helps a person detect threats, functional MRI brain scans revealed. The results help explain why screams are so distinctly alarming.