week's time. As the story goes, Teuber spent many months researching the question--day and night--until he realized that the solution was impossible. There simply was not enough information on how the brain controls movement. He returned, dejected and frustrated, to his mentor, essentially empty-handed for his efforts. Lashley smiled encouragingly and informed him that, just as there was no answer available for such a "simple" motor-control problem, so also was there a lack of knowledge regarding Teuber's problem in perception. There is a message here: We have a long way to go before we can understand even the simplest of motor skills. The following chapters are as much a testimony to this fact as they are a representation of the status of our current thinking.
Postscript. There is a humorous outcome of the Teuber-Lashley dialogue. Throughout the many years that followed this incident, Lashley and Teuber had a secret way of communicating with each other, often in crowded rooms. The sign of recognition from Lashley to Teuber was a "tweak" of the index finger! Teuber was to tell this story many years later to a group of scientists whose main endeavor was to understand the nature of movement control.
Preparation of this chapter and this volume was supported by NSF Grant No. SER 77-02986.
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