Single session motor learning demonstrated using a visuomotor task: Evidence from fMRI and behavioural analysis

There is a continuing need to improve understanding of the central nervous system control of learning. Specifically, there is a need to examine the characteristics of cortical and sub-cortical activity linked to the stages of motor learning, including those occurring within a single-session. In this study we sought to design and investigate a visuomotor task to determine its ability to assess the component of motor learning occurring during a single session of fMRI (i.e., the 'online' improvement in motor performance). Fourteen healthy control subjects performed a visuomotor task requiring a combination of bilateral grip force to accurately move a cursor towards a target. We assessed online motor learning by comparing behavioural measures (accuracy and error magnitude) and the extent of spatial activation in specific brain regions of interest (ROIs) using fMRI pre- and post-training. Results showed a training-related improvement in performance based on increased accuracy (p < 0.0125) and decreased error magnitude (p < 0.0125) from pre- to post-training. Decreases in the extent of spatial activation from pre- to post-training in the majority of ROIs supported a training-related attenuation in brain activity associated with online motor learning. Importantly, decreases in error magnitude across conditions (p < 0.05) confirmed that improvements in performance continued over the entire course of the experiment. Establishing this task may permit more extensive study of the neural correlates of single-session, online learning in healthy individuals and those with motor control challenges. Information obtained from such studies may provide an opportunity to improve interventions in neurological rehabilitation. (C) 2012 Elsevier B.V. All rights reserved.