What Is the Most Annoying Sound in the World? | Science | Smithsonian

What Is the Most Annoying Sound in the World? | Science | Smithsonian: Even more interesting than the rankings were the parts of the brain that lit up with activity when the research participants heard the irritating noises. The MRI scans revealed that along with the auditory cortex (which processes sounds), activity in the�amygdala—the region of the brain responsible for producing emotions—increased in direct proportion to the perceived unpleasantness of the sound. The researchers found that the amygdala interacted with signals coming from the auditory cortex, increasing the amount of unpleasantness conveyed by sounds at the top of the list, which all happen to occur in the�frequency range�between 2,000 and 5,000 Hz.