Unlearning Is Not Inevitable:Newly Formed Sensorimotor Memory During Motor Adaptation May Not Necessarily Decay

Motor adaptation refers to the process of active adjustment of a skilled action.in order to adapt to the influence on the action after the change of the environment or individual state.In the process of motor adaptation,sensorimotor memory will be revised.Current models of motor adaptation assume that the newly formed sensorimotor memory in the process of motor adaptation will decay rapidly in a short time without visual error feedback.This view holds that the new memory generated by motor adaptation is unstable and will decline naturally(the intrinsic decay hypothesis).The supporting evidence for this view is mainly the experimental results of simple movements(e.g.reaching tasks).However,according to classical memory theories,sufficient context cues can help people code and retrieve memories.Therefore,this study explored the role of context cues in encoding and maintaining sensorimotor memory under relatively complex tasks.Using the throwing task in the virtual environment as a paradigm,this study uses motion capture equipment to record the participants' movements,and control the feedback form of motor learning by virtual reality technology.The trajectory of the throwing ball was used as context cues.Experiments 1 examined the effect of context cues on motor adaptation and found that relatively sufficient context cues could help subjects better adapt to perturbation and encode sensorimotor memory.Experiments 2 further examined the effect of context cues on the retention of sensorimotor memory.When encoding,the subjects in each group experienced the same context cue;and when retrieving,the more consistent the context cue is,the more likely the subjects were to maintain the newly learned action.Experiment 3a and experiment 3b were used to find out whether the decline of motor adaptation level was due to forgetting.When the context cues were reintroduced at the maintenance stage,the results showed that the subjects could return to their previous learning level.Experiment 4.as a control experiment,excluded the hypothesis that only rendering a trajectory makes the ball throw farther.The above results show that for relatively complex motor tasks,the newly formed sensorimotor memory does not fade rapidly when there are sufficient situational cues and the same situational cues are maintained in the test stage;richer clues in learning can help subjects to better adapt to motor activities;and providing situational cues consistent with learning can help subjects better in recalling.To maintain the newly established sensorimotor memory.