On the relation among speech errors, disfluencies, and self-repairs

In this study the relationship between speech errors (deviations from a speech plan), disfluencies (interruptions in the execution of a speech plan), and self-repairs (corrections of speech errors) was examined. Two hypotheses were formulated: Either disfluencies are special types of speech errors, or they resemble self-repairs (i.e., they are corrective actions applied to anticipated, internal errors). To test these two hypotheses, patterns of speech errors, disfluencies, and self-repairs were compared in a task in which speakers recited stimulus sentences four times in succession under time pressure. Subjects in one condition were explicitly instructed to pay close attention to accuracy of speaking. In another condition subjects were told that speech accuracy was not important. A much lower speech error rate was found in the higher-accuracy condition, but rates of disfluencies and self-repairs did not differ significantly between the two accuracy conditions. This is regarded as support for the self-repair account of disfluencies. When accuracy of speaking is stressed, speakers tend to avoid and repair speech errors at the cost of reduced speech fluency.