Split-brain studies of music perception and cognition

Abstract

The biological basis of music perception and cognition is explored from the perspective of empirical work with brain-damaged patients. By examining patients whose left and right cerebral hemispheres have been surgically separated, the role of each half-brain in music processing can be assessed. This approach was used to analyse the lateralization of brain mechanisms mediating timbre discrimination and recognition. We found that each hemisphere of our split-brain patients was able to recognize musical instrument timbres, and that the left hemisphere was superior to the right; on the other hand, only their right hemispheres were able to discriminate subtle differences in timbre between pairs of steady-state harmonic spectra which had no cognitive referents outside the auditory domain. These observations suggest that acoustic-discriminative and semantic-associative processes mediating timbre perception are differentially distributed within the two half-brains. In addition, they emphasize the need to use real...