Specificity in practice benefits learning in novice models and variability in demonstration benefits observational practice

Considerable research has shown that both demonstration and verbal instruction can facilitate learning of a motor task in inexperienced individuals. In the current study, verbal instructions were used as a means to reduce the discovery learning process and control the amount of trial-to-trial variability in demonstrations. The task required models to learn to trace a pair of circles with a 90°-relative phase pattern between the arms. Verbal instructions directed one group of models toward a single strategy, and this group improved at a faster rate and performed better in a 24-h retention test compared to a group of models in a discovery learning context. The discovery models utilized multiple strategies throughout the practice. Each model was watched for 2 days by an observer, who was instructed that they would have to produce the 90°-relative phase pattern on day 3. Observers, who watched the discovery models, performed better than those who watched the single strategy models. The results support two primary conclusions. First, trial-to-trial variability associated with strategy selection processes in a model benefits an observer by facilitating perceptual discrimination processes that may play a key role in action generation. Second, verbal instructions that reduce discovery learning during physical practice benefit acquisition and retention performance when the task has multiple strategies wherein no one strategy guarantees the best performance outcome.