What a Scream Does to Your Brain
The sound of a scream goes right to the fear centers of our brain, suggests a new study published in the journal Cell Press.
New York University and University of Geneva scientists listened to YouTube videos and people screaming into a sound-booth microphone to analyze what screaming does to the brain. They wanted to focus specifically on high-quality screams and screamed phrases that were distinguishable from other loud or high-pitched sounds.
As part of their research, the scientists used a new method of sound analysis called the modulation power spectrum (MPS). This technology shows the rate of sound intensity changes and identified an acoustic sound range that is specific to screaming, not regular speech. This approach identified a sound quality associated with screaming called roughness, meaning that volume rises dramatically and fast.
Through a series of experiments, the scientists confirmed the sound of screaming is unique within the auditory spectrum of what the brain responds to, even across languages. Only ambulance sirens and car alarms had a similar affect on the amygdala, the so-called fear center of the brain.
The study also found the higher the roughness, the scarier that the sound registers with the brain. Candidates listened to screams and sounds while their brain activity was monitored. When the roughness was manipulated to be higher, activity in the amygdala increased as well.