Contextual interference: single task versus multi-task learning.

This experiment examined contextual interference in producing a bimanual coordination pattern of 90 degree angle relative phase. Acquisition, retention, and transfer performance were compared in a single-task control group and groups that performed 2 tasks in either a blocked or random presentation. Surprisingly, acquisition data revealed that both the random and control groups outperformed the blocked group. Retention data showed a typical CI effect for performance variability, with the random group outperforming the blocked group. Neither the random nor blocked groups outperformed the control group, suggesting interference of a second task may be as beneficial to learning as extra practice on the initial task. No group effects were found during transfer performance. Results suggest that random practice is beneficial for learning only one task.