Considerations of Intention and Movement: Action Plans and Motor Programs in Speech and Keyboard Entry

Abstract

The cognitive organization and control of rapid movement sequences was investigated in speech and keyboard entry. Five reaction time experiments were carried out with various manipulations of stimulus meaning. A linear increase in reaction time with an increase in the number of items to be produced was evident for spoken lists of random digits, single words in random order, and repeated syllables but not for single words arranged into meaningful context. A speech interference condition produced a linear increase in reaction time in a key pressing task when it was necessary for the action to be planned ahead of time. These results indicate that meaningfulness of stimuli facilitates movement organization, an effect which can have significant impact on input technology.