Why do some high pitched sounds (ex. screeching of a chalkboard) cause some to cringe uncomfortably, while others are seemingly unaffected?
A study by Newcastle University found that being annoyed by certain sounds comes from high levels of activity between certain brain regions that process emotion and the auditory cortex, a region that processes sound [4]. Specifically, the amygdala and auditory cortex were found to be active when we hear certain sounds [1, 4]. The researchers conducting the study found an abnormality in the emotional control mechanism of the brain in people with misophonia, a condition in which people are disturbed by specific sounds that may be soft or loud [3]. Brain scans revealed that activity in people with the condition originates from a different connectivity pattern in the frontal lobe, which normally suppresses an abnormal reaction to sounds [3]. The study also found that sounds that have frequencies ranging from 2,000 to 5,000 Hz are considered unpleasant [4].
The reason some high pitched sounds cause some people to cringe while others are seemingly unaffected is due to the sounds activating the amygdala [1]. The amygdala is a sentry that activates when unpleasant sounds are heard [1]. When the amygdala is activated, the auditory cortex is activated to analyze the sound in a more pervasive and emotional way [2].