The Organization of Action Sequences: Evidence From a Relearning Task.

In two studies, the organization of sequential behavior in transcription typing was investigated. The design of the studies made it possible to test the hypothesis that sequential skill in typing resides only at an abstract, effector-independent level. Skilled typists (N = 12) learned to type on an altered keyboard in an experimental paradigm that allowed only certain components of the motor control system to adapt to the alterations. When performance was compared on a pretest and a posttest, various decrements in the typists' speed and accuracy were observed. The forms of these decrements provided evidence against a strong form of the effector-independent hypothesis.