Concept: Performing voluntary, coordinated movement requires preparation of the motor control system.
After completing this chapter, you will be able to
Discuss why reaction time (RT) can be an index of preparation required to perform a motor skill
Explain how Hick's law describes the relationship between the number of alternatives in a choice-RT situation and RT
Describe various task and situation characteristics that influence action preparation
Describe various performer characteristics that influence action preparation
Discuss several motor control activities that occur during action preparation
Many sport, recreation, fitness, and daily activities demonstrate our need to prepare the motor control system to carry out an intended action. For example, many sports events, such as running, swimming, and trap shooting, incorporate the importance of preparation into the rules of the activity by requiring an audible signal warning the competitors to get ready.
Certain performance characteristics of activities also provide evidence of the need to prepare for the action. For example, when you decide to pick up a glass of water for a drink, there usually is a slight delay between your decision and the intended action. In another example, if you are driving a car along a street and another car unexpectedly pulls out in front of you, there is a measurable time delay between the moment you see this and the moment you begin to move your foot off the accelerator and onto the brake pedal. In each of these very different activity scenarios, the initial movement of the intended action is preceded by an interval of time in which the motor control system is prepared according to the demands and constraints of the situation.
Consider the preparation of action from a different perspective. Undoubtedly, at some time or other you have said, following a poor performance in an activity, I wasn't "ready." By saying this, you imply that if you had been "ready" you would have performed much better than you just have. Or, if you work with physical therapy patients, you undoubtedly have heard one tell the therapist, "Don't rush me. If I get out of this chair before I'm ready, I'll fall."
Application Problem to Solve Describe a motor skill that you perform or that you teach other people to perform. Describe the motor control characteristics of this skill that you, or the people you teach, must prepare to perform the skill successfully. Are there situations in which there are fewer or more characteristics to prepare? What are these situations and how do they influence the need to prepare fewer or more motor control characteristics?
In chapters 5 through 7, we focused on factors influencing the control of the performance of a skill. Although there was occasional mention of the initiation of the action, we only touched on what is involved ...