ICMPC Day One – Key note

This week I am in Seattle at the 11^th International Conference of Music Perception and Cognition. It is typically the world’s biggest meeting in the field of music psychology. It is a chance to hear about the latest research, meet collaborators and discuss new projects, and to meet those people whose names you know so well from books and papers 🙂

This year ICMPC is being held in Seattle.  So far I am having a great time! I arrived on Saturday night after 16 hours flying. Sunday, my partner Oscar and I did some typical Seattle sight-seeing. We went to the Pike Place market and ate ‘New England’s best chowder’ at Pike Place Chowder. Then we walked along Elliot Bay, along sky-scrapper alley, took a little cruise around Lake Union (including seeing the ‘Sleepless in Seattle’ houseboat) and finally went to a fantastic jazz club to see Shemeika Copeland. Man, that lady can sing!!

Then Monday comes, and I was bouncing down to the conference at 8am. The first talk was a key note given by Gottfried Schlaug, who is the Director of the Music and Neuroimaging Laboratory and the Stroke Recovery Laboratory, and Division Chief of Cerebrovascular Diseases, as well as Associate Professor of Neurology at the Beth Israel Deaconess Medical Center and Harvard Medical School . In short, he is an expert! His talk was entitled ‘Singing: When it helps, when it hurts and when it changes brains’.  I have devoted an entire blog to this talk as it was packed with information.

Professor Schlaug defined singing as a specialized vocal behaviour that integrates auditory and sensorimotor information, and called it ‘the most direct form of music making’. Singing, he argued, is a rich source of data for study in music psychology since it has an analogous animal model, an example of a human disorder, and then there is the case of music therapy.  He then helpfully summarised the main forms of neuroimaging he presented in his talk, including fMRI morphometry (voxel based morphometry (VBM) for detecting differences in groups and deformation based morphometry (DBM) for seeing long term changes in the same brains), and Diffusion Tensor Imaging (DTI). Personally I love the diagrams that emerge from DTI. I can’t find any as good as the ones the professor showed in this talk sadly, but here is an idea of the type of thing you see. DTI works by detecting the random diffusion of water molecules in the brain which occurs along white matter fibre tracts. The higher the rate of diffusion, the more fibres are aligned in one direction along a tract.

His first section, ‘when music helps’, focused on the brain effects of musicianship. He presented evidence from his 2003 study that showed higher levels of grey matter in sensorimotor cortex, premotor cortex and adjacent parietal regions in professional musicians compared to nonmusicians. The differences correlate with the amount of practice. Other differences include grey matter increases in primary auditory cortex, inferior frontal gyrus, and middle-inferior frontal gyrus. In summary this study provides a ‘road map’ of changes in the musician brain that respond to the duration and intensity of musical practice.

Then the professor presented evidence from his longitudinal study of children learning musical instruments. This study provides the crucial link between looking at differences in musicians and nonmusicians brains, and showing that these changes actually RESULT from training rather than being premorbid. After a year of lessons children who took lessons are already showing changes in the areas identified by the 2003 study. DTI is also showing changes in a fibre bundle known as the arcuate fasciculus (Latin, curved bundle; AF) which is the neural pathway connecting the posterior part of the temporoparietal junction with the frontal cortex in the brain. This pathway appears to be more and more important in music processing.

Next we moved onto ‘when it hurts’, a summary of singing deficiencies in tone deafness. The professor summarised his really interesting findings regarding AF disconnection in amusics.  Then there was mention of older structural studies which have shown differences in left superior temporal sulcus and inferior frontal gyrus, as well as right hemisphere cortical thickness. The professor ended this section by presenting some of the latest DTI evidence investigating the AF in amusics. Previously he had shown that AFs in amusia were weaker and sparser, but there was a new interesting point about where the fibres actually go in the brain. Turns out that instead of projecting forward, the AFs in some amusics project up into the parietal lobe. Hardly any make it to the superior temporal gyrus, which the professor argues is a crucial junction for allowing auditory feedback.

Finally we moved onto ‘when it changes brains’ which was a collection of evidence surrounding the effects of Melodic Intonation Therapy. MIT is used in patients with communication disorders, typically following left hemisphere strokes. It involves teaching the patient to sing words in order to help them speak again. As usual there were some amazing videos of patients who have been helped by this therapy. The professor then showed brain scans from these patients and revealed how the MIT was associated with new stronger activation in the right hemisphere and increased volume of the AF. He is now in the process of conducting a randomised clinical trial of MIT with his newly developed control therapy which he calls ‘speech repetition therapy’. This is like MIT in all aspects but does not include the pitch singing component or the hand tapping. It will be really interesting to see if the MIT shows superior effects compared to this clever control.

In conclusion, singing engages an auditory-motor feedback and feedforward network loop in the brain across both hemispheres that can be enhanced by musical training and appears weaker or disconnected in cases of congenital amusia. Finally, in cases of left hemisphere stroke, MIT can encourage development in the right hemisphere network and bring improvements in communication.

All in all, a thoroughly engaging tour around Professor Schlaug’s research program which has provided so much evidence regarding the behavioural and neural correlates of musical learning, skill acquisition, and brain adaptation in response to changes in the environment or brain injury in the developing and adult brain. This week is off to a flying start!