Two movement goals underlying imitation | Action Club Seminars in Motor Control and Coordination
November 5, 2021 @ 03:45 pm to 05:00 pm
Aaron Wong, Moss Rehabilitation
127 Noll Lab
University Park
Our ability to rapidly and efficiently acquire a rich repertoire of complex motor behaviors relies in part on our capacity to learn through observation and imitation. Loss of imitation ability is observed in the neurological disorder of limb apraxia, one of the strongest predictors of poor post-injury recovery and increased caregiver dependence after left-hemisphere stroke. Despite its importance, our understanding of how we translate observed movements into motor commands for action remains poorly understood. In this talk, I will share recent work in my lab that begins to unpack the mechanisms supporting imitation. Our work suggests that there are actually two ways to specify movement goals: as body configurations or as end-effector trajectories, and that our choice of movement goal depends largely on task demands. We demonstrate that both kinds of movement goals may be impaired in apraxia, with these two kinds of deficits associated with damage to different brain regions. We then probe the nature of these imitation goals, and demonstrate the importance of representing both how our movements should look and how they ought to feel. Collectively, this work begins to bridge the gap between cognitive conceptual models of imitation and motor-control models of movement production by identifying the underlying intermediary representations supporting imitation, and sheds light on what may be contributing to impairments in patients with apraxia following a stroke.