Bridging the divide between laboratory and "real world" in stuttering

Stutterers stutter significantly less in the laboratory and the clinic than in everyday speaking situations. This paper reviews pertinent literature to show that, in the outside world, stutterers have a stake in what they say and therefore message content and interpersonal dynamics command attention-relegating speech-motor planning and execution to an automatic, memory-based process called speech concatenation. In the laboratory and the clinic, content of communication and interpersonal dynamics are less important, allowing stutterers to concentrate on the motor planning of articulation and prosody. Evidence reviewed here suggests that speech construction (real time preparation of an utterance motor plan) is incompatible with stuttering. Evidence also suggests that a slight delay in retrieving motor plans from memory during speech concatenation is the immediate source of stuttering.