Montreal: A new study has found that brains of people who are victims of tone-deafness do not have enough of white matter. The study, available in the current issue of Brain, was conducted by a team of researchers from the Université de Montréal, the Montreal Neurological Institute and the Newcastle University Medical School. Tone deafness (or congenital amusia) is known to last a lifetime which impedes normal functioning people to learn even fundamental music skills. The study investigated the structural neural correlates of tone deafness.
Magnetic resonance imaging data from a group of tone deaf people were compared with the images of people with normal musical ability to find out what area of the brain was responsible for this condition and what possible anatomical anomaly could correlate with this "music disorder."
"The results were consistent across samples in highlighting a reduction in white matter concentration in the right inferior frontal gyrus of amusic individuals," explained Dr. Isabelle Peretz of the Université de Montréal. "The data points to the integrity of white matter tracts in right frontal brain areas as being key in acquiring normal musical competence."
"We used a technology called voxel-based morphometry (VBM), which is a computerized and automated procedure that allows one to search throughout the whole brain for structural differences in terms of brain tissue concentration," explained Dr. Krista L. Hyde of the Montreal Neurological Institute at McGill University and the Department of Psychology at the Université de Montréal. "The individuals who participated in the study were considered tone-deaf on the basis of two main criteria: difficulty recognizing familiar tunes without the assistance of lyrics, and the inability to detect when they are singing out of tune."
The present study constitutes the first investigation into the structural neural correlates of tone deafness. The results have implications for the understanding of normal acquisition of musical abilities and for the diagnosis and remediation of this music-specific disorder.