ROBOT-AIDED FUNCTIONAL IMAGING - APPLICATION TO A MOTOR LEARNING-STUDY

The purpose of this study was to examine the neural activity underlyin g an implicit motor learning task. In particular, our goals were to de termine whether initial phases of procedural learning of a motor task involve areas of the brain distinct from those involved in later phase s of learning the task, and what changes in neural activity coincide w ith performance improvement. We describe a novel integration of roboti c technology with functional brain imaging and its use in this study o f implicit motor learning. A portable robotic device was used to gener ate forces that disturbed the subjects' arm movements, thereby generat ing a ''virtual mechanical environment'' that the subjects learned to manipulate. Positron emission tomography (PET) was used to measure ind ices of neural activity underlying learning of the motor task. Eight h ealthy, right-handed male subjects participated in the study. Results support the hypothesis that different stages of implicit learning (ear ly and late implicit learning) occur in an orderly fashion, and that d istinct neural structures may be involved in these different stages. I n particular, neuroimaging results indicate that the cortico-striatal loop may play a significant role during early learning, and that the c ortico-cerebellar loop may play a significant role during late learnin g. (C) 1998 Wiley-Liss, Inc.