One useful addition to the collection of activities in a practice session is to ask the learner to rehearse skills to be learned mentally, without performing actual, overt physical practice. In such mental practice the learner thinks about the skills being learned, rehearses each of the steps sequentially, and imagines doing the actions that would result in achieving the goal.
Can this method actually contribute to learning? For many years, scientists and educators in the motor learning field had very much doubted that motor learning could be accomplished through mental practice. The understanding of practice and learning at the time held that overt physical action was essential for learning. Most researchers thought that mental practice was producing gains in the cognitive–conceptual aspects of the task, and it was difficult to understand how any learning could occur without movement, active practice, and feedback from the movement to signal errors.
However, evidence from various experiments has demonstrated convincingly that mental practice procedures actually generate motor learning. Although mental practice does not result in as much learning as the same amount of physical practice, it does result in far more improvement than in no-practice control groups (see Feltz & Landers, 1983, for a review). Figure 10.4, from Hird and coauthors (1991), provides results from two separate tasks, the pegboard and pursuit rotor tasks. The fact that mental practice generates learning in the pursuit rotor (for example), which does not seem to have much cognitive learning involved beyond the first few trials, suggests strongly that the learning of motor control must be involved with mental practice.
How Does Mental Practice Work?
There are several views regarding how mental practice generates new task learning. One idea is that mental practice facilitates the learning of “what to do” (Heuer, 1985). For example, a tennis player could decide what shot to take; a baseball player could think how to grip the bat; and a skier could rehearse the sequence of turns in the ski run. These cognitive elements are thought to be present only in the very early stages of learning (the cognitive stage discussed earlier); thus, mental practice effects were predicted to apply only to early learning as well. Although learning cognitive elements is undoubtedly a major factor in mental practice, evidence such as that illustrated in figure 10.4 (and in Focus on Application 10.1) suggests that there is more to mental practice than just this. Beyond these early stages of practice, both the pegboard-insertion task and the pursuit-rotor task involve considerable motor control learning, as these tasks seem largely devoid of cognitive or conceptual components. Rawlings and coauthors (1972) also studied mental practice with the rotary-pursuit task, and their results were very similar to those of Hird and colleagues. Clearly, mental practice is not just cognitive or symbolic learning.
Another, older notion is that during mental practice, the motor system produces minute contractions of the participating musculature, with these contractions being far smaller in amplitude than those necessary to produce action. On this view, the “movement” is carried out in the central nervous system, providing “practice” even without overt body movement. Although EMGs (electromyograph recordings of the muscles’ electrical signals) do show some evidence of weak activities during mental practice, the patterning of these EMGs does not resemble that of the actual movements very closely, making it difficult to understand how these electrical activities alone could be the basis for enhanced learning. This idea that mental practice produces minute muscular contractions has not generated much research support.When and How to Use Mental Practice
The learner needs to be instructed carefully in the methods of mental practice. It is not enough simply to suggest that the learner go somewhere and “practice mentally”; systematic procedures are necessary. Weinberg and Gould (2011) provide additional tips for maximizing the use of imagery and mental practice, such as performing imagery and mental-practice activities in as many different settings as possible. Because mental practice and imagery require no apparatus; large groups of learners can practice at the same time. The clever instructor will find ways to interleave the two practice modes to provide maximal gains, for example by urging mental practice during the rest phase between trials of a fatiguing task or to break up a long string of repetitious physical practice trials.Focus on Application 10.1Mental Practice in Stroke Rehabilitation
The application of mental practice as a method to improve motor skills has been a part of sport for years. In some sports the facilities are restricted to seasons of the year, therefore mental practice would be a perfect fit for practicing sport in the off-seasons when facilities are not available. When research on mental practice, such as that shown earlier in this chapter, began to reveal positive effects on motor learning, instructors and therapists began to use these methods in their teaching and therapies, respectively—
notably, in stroke rehabilitation they were justified in using these methods.
Stroke is a medical condition that results in damage to the brain. Often the damage is to one side (hemisphere) of the brain, resulting in motor control impairments to the opposite side of the body. The goal of rehabilitation is to regain function by repairing the brain through goal-directed movements. Continued activations, from active physical practice, can lead to partial or full restoration and compensation.
But, there are limitations to the amount and frequency of rehabilitation treatments involving a therapist. Active movement outside therapy times may be encouraged, but unless specified and monitored, may not always be wise (e.g., for various reasons). Fortunately, recent research has shown that mental practice (and imagery) generates neural activations of the brain that are similar to actual movement (Garrison, Winstein, & Aziz-Zadeh, 2010). Since mental practice cannot replace physical rehabilitation as an effective therapeutic technique, the combination of physical and mental practice is more effective than either form alone (Cha et al., 2012; Dickstein & Deutsch, 2007; Nilsen, Gillen, & Gordon, 2010). There appears to be little doubt that mental practice serves as an effective addition to the occupational and physical therapists’ arsenal of rehabilitation tools.