The effects of musical training and cerebral asymmetries on perception of an auditory illusion.

Twenty-seven right- and fourteen left-handed subjects with varying amounts of musical training listened to dichotic octave patterns. Each pattern consisted of twenty 250-msec. tones which oscillated from 400 to 800 Hz. Patterns were combined in such a way that while one ear received a 400 Hz tone, an 800 Hz tone was simultaneously present in the opposite ear. Reported perception of these patterns was significantly related to the handedness of the subjects. In addition, responses of subjects with musical training differed significantly from those of untrained subjects. An hypothesis is suggested that musical training serves to establish a sharper psychophysical criterion for judging unfamiliar sounds. Further research should be directed toward understanding the relationship between the octave illusion and cerebral dominance.