their actions but the information in the environment that enables them to set up the parameters for the motor system in the first place. This tuning effect may take place at different levels in the system, for example, in cortical, spinal, and even receptor systems such as the muscle spindle.
Speculating further, early skill development, according to this notion, might be characterized by an inability to take advantage of feedforward control; that is, the beginner is not sensitive to what the effects of his/her movements will be and hence must rely on continually monitoring peripheral information. Higher levels of skill, on the other hand, are characterized by an apparent improvement in processing peripheral information; the capacity to process incoming information is, in a sense, less limited than before. According to the "tuning" hypothesis, this improvement is due at least in part to enhanced feedforward control that enables the performer to attend to other regulatory details in the environment.
In conclusion, it is quite apparent that many of the details of the relationship between feedforward and feedback in contributing to skilled performance have yet to be worked out. In the following chapters you will perceive differing biases on their relative roles. I think it is fair to say that the whole notion of feedforward and its operation has not received the theoretical attention that feedback has. Yet, even though feedforward is an elusive issue to examine experimentally, it may play a significant role in skilled movement. Time and the burden of scientific evidence will prove me right or wrong.
Preparation of this chapter and this volume was supported by NSF Grant No. SER 77-02986.
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