The plastic human brain

Purpose: In this review I summarize and discuss reported findings of structural and functional plasticity in the intact human brain. Methods: The main focus is placed on research that uses musicians as a model to study brain plasticity. I summarize therefore mostly studies dealing with musicians or with the effect of music practice. In the first section, structural plasticity is described on the basis of modern neuroanatomical studies using magnetic resonance imaging (MRI) techniques. In the second part, emphasis is given to studies reporting functional plasticity on the basis of changed neurophysiological activation patterns. These studies are discussed in the context of two approaches employed to study plasticity in the human brain: the cross-sectional and longitudinal approaches. Results: The reviewed studies altogether indicate that experience can shape brain anatomy and brain physiology. Brain plasticity as demonstrated here is related to changed grey and white mater densities (and volumes) but also to changed activation patterns in the brain areas involved in controlling the expertise task. Conclusions: Taken together, all studies support the view that the human brain is much more plastic than had been anticipated 20 years ago