Brain roots of music depreciation.

Some people are inept at all things musical, whether it's playing an instrument or just recognizing a melody. Preliminary data suggest that these individuals' brains are, literally, out of tune.

Neuroscientists Krista L. Hyde and Isabelle Peretz, both of the University of Montreal, subjected 10 volunteers with these musical deficits to pitch shifts comparable to those that occur when someone plays one key and then the next key on a piano. None of the volunteers noticed a difference between the tones.

However, the same people--all of whom had great difficulty telling different melodies apart and remembering simple tunes--accurately tracked timed sequences of musical tones and noted slight changes in timing. Ten other volunteers with normal tone perception and musical aptitude also scored well on the timing test. This result indicates that it's pitch, not timing, that lies at the heart of severe musical ineptitude, sometimes referred to as amusia.

To Hyde and Peretz, the results suggest that the brain's capacity to perceive modest pitch changes may be impaired from birth in persons with amusia. As a result, such individuals never grasp the overall structure of musical passages.

The researchers describe their study in the May Psychological Science.