Vision,
proprioception and arm movements: reach adaptation as a model for studying the
dynamics of sensorimotor learning
Philip N. Sabes
Accurate control of visually guided arm movements requires the integration of spatial information from visual and proprioceptive sensory streams. This integration, in turn, relies on well-calibrated sensory transformations to bring signals from the two modalities into alignment. In fact, these transformations are remarkably plastic, as evidence by the well-studied phenomenon of prism adaptation. In our laboratory, we study a modern variant of prism adaptation, in which subjects adapt to shifted visual feedback in a virtual feedback environment. In this workshop, I will report on our efforts to understand the nature of this adaptive response and what it tells us about sensory integration. We have developed a novel psychophysical approach to identifying the separate components of this adaptive response. Using this approach, we can distinguish between plasticity in sensory alignment and adaptation in motor planning and execution.
Combining these psychophysical tools with models of the trial-by-trial changes during learning, we have been able to identify the sensory feedback signals that drive adaptation