Articulatory behaviors associated with stuttering: a cinefluorographic analysis.

High speed (150 fps) cinefluorographic techniques were used to record articulatory movements during fluent and disfluent speech from four stutterers and control utterances from one normal speaker. Analyses of 11 perceptually disfluent utterances are reported. The results show: (1) interarticulator positions occurring in both perceptually fluent and disfluent utterances of stutterers were unlike those in fluent utterances of a normal speaker; (2) aberrant interarticulator positions preceded repetitive movements and static posturing; (3) consistent interarticulator repositioning which precedes termination of an oscillatory movement or static position often results in: (a) the lowering of the jaw or lip, and or (b) tongue shapes which resemble shapes found in normal speakers' fluent productions or the resting tongue shapes of the stutterer. The systematic repositioning and other patterns found are discussed in terms of possible neuromotor mechanisms involved in disfluency. It is suggested that reflex interactions among the muscles of articulation might account for some of these effects. A brief discussion of theoretical and therapeutic implications is included.