Long-term Retention of Proprioceptive Recalibration

Abstract

Proprioception is recalibrated following reaches with misaligned visual feedback of the hand, such that one’s sense of felt hand position is shifted in the direction of the visual feedback provided (Cressman & Henriques 2009). In the current experiment, we examined the ability of proprioceptive recalibration to be retained over an extended period of time (i.e. 4 days), and the benefits of additional training on retention in the form of recall and savings (i.e. faster re-learning on subsequent testing days). Twenty-four participants trained to reach to a target while seeing a cursor that was rotated 30° clockwise relative to their hand on an initial day of testing. Half of the participants then completed additional reach training trials on 4 subsequent testing days (Training group), whereas the second half of participants did not complete additional training (Non-Training group). Participants provided estimates of their felt hand position on all 5 testing days to establish retention of proprioceptive recalibration. Results revealed that proprioceptive recalibration was recalled 24 hours after initial training and that there was no benefit of additional training. Retention in the form of savings was observed on all days for the Training group and on Day 5 in the Non-Training group. These results reveal that proprioceptive recalibration does not benefit from additional training but is retained in the form of recall and savings. Taken together, results from the two groups of participants showed that the sensory system’s ability to change over time appeared to saturate early on, within two days of training. Moreover, the different time scales (i.e. 1 day for recall versus 4 days for savings), suggested that distinct processes may underlie recall and savings of proprioceptive recalibration.