Timing in the Motor Programming of Typing

In developing a theory of motor programming of skilled performance it has been suggested that an abstract, structural representation in the program specifies both a sequence of responses and expressive features of the sequence, such as timing, stress and intonation, which are mapped separately into the response output. In the case of typing, which does not require expressive features, it has previously been assumed that response timing is governed more simply by a timekeeper providing a stochastically regular beat. Two sets of specially constructed texts were given to a fast typist and the results support the idea that skilled typing is paced by a regular beat. They also show that there were systematic rhythmic departures from the beat, which arose from contingencies of keyboard movement but were not the simple consequences of these; rather they may be regarded as structured anticipations of the contingencies, and as such are analogous to the expressive features of speech and playing music.