The role of myelin in experience-dependent white matter plasticity. (360G-Wellcome-090955_Z_09_A)

The adult brain shows dynamic structural changes with learning and with recovery from damage. Studies in animals are able to characterise such changes with exquisite detail. The vast majority of these studies have focussed on changes occurring in grey matter. We recently provided evidence for learning-related change in the microstructure of white matter pathways of the adult human brain. However, the measures provided by neuroimaging are relatively crude and non-specific and, thus far, have no t been related to specific underlying cellular mechanisms. The current proposal has two main aims: First, to investigate the functional and clinical significance, timecourse, and age-dependence of experience-dependent white matter and grey matter change. Second, to carry out parallel neuroimaging and histological studies in rodents in order to determine mechanisms underlying change detected on imaging. The results of the animal studies will be relevant not only to those with an interest in plas ticity but also to the wider imaging community, as they will shed light on the anatomical basis of structural imaging measures.