Temporal dynamics of adult brain plasticity: Effects of motor learning on brain anatomy and cognitive functions in adulthood

PI: Claudio Brozzoli, Claudio.Brozzoli@ki.se

This project aims to extend our knowledge of the anatomical changes in different regions of the brain caused by motor learning and of how these changes relate to learning, particularly cognitive performance. I hypothesize that initially, brain structures will increase in volume because of a learning-dependent volumetric increase that reflects local neural “rewiring.” Then, once optimal rewiring has occurred, volume may drop somewhat, moving closer to pre-training levels.

After childhood, the brain’s ability to change physically in response to experience—its plasticity—diminishes. Nevertheless, adults retain some plasticity, which supports learning, maintenance of mental functioning as we age, and recovery from brain damage. When adults learn, structures in the brain can both increase and decrease in size. There is much we do not yet know about these changes, including how fast they materialize, which regions of the brain that can change, how these regions change, and whether the changes are caused by learning or just practice. We are also unsure whether untrained abilities that rely on neural circuits altered by the change are also affected. At present, we only have snapshots of the brain before and after training. Thus, previous studies’ mixed results may stem from a lack of information about the dynamic process of anatomical changes in the brain during and after learning.

In a series of studies on humans, my research team will investigate brain structure and activity acquired via dense longitudinal multi-modal magnetic resonance imaging and behavioral measures of performance. The project has three aims. First, we will demonstrate whether acquiring a new motor skill causes temporary changes in brain structures devoted to motor control following an initial increase in volume and a subsequent renormalization. Second, we will investigate whether the myelin component of training-dependent structural changes in the motor network reflects behavioral learning (improvement in performance) rather than intense practice. Third, we will examine whether anatomical changes in the brain caused by motor learning affect untrained mental functions that rely on activity of the brain areas affected by motor learning.

The parallel monitoring of brain and behavior during training will shed light on plasticity and the progression of local changes in the adult brain over time. The resulting insights will pioneer new strategies to improve learning in adulthood and boost functional rehabilitation in people with brain damage.

The project is funded by a grant from the Swedish Research Council.