Anxiety disorders could involve not only cognitive, but also sensory changes in the brain.

Recent studies have suggested that people with anxiety, after learning a negative stimulus, respond negatively to similar but neutral stimuli more often than healthy people. Rony Paz at the Weizmann Institute of Science in Rehovot, Israel, and his colleagues found that individuals with anxiety disorders also perceive these stimuli less precisely than healthy people do. After learning to associate a tone with either monetary gain or loss, participants were asked to decide whether a series of other sounds were a match to the previous ones or were new. People with anxiety disorders mistook a wider range of frequencies for the tones they had learned, compared with healthy people. Learned tones and neighbouring sounds triggered brain activity that showed greater similarity in people with the disorders than in healthy people. This effect was in the brain's auditory cortex and in the amygdala, which processes fear.

The findings suggest that people with anxiety have altered perception of certain stimuli, the authors say.

Curr. Biol. http://doi.org/bc3z (2016)