I modelli funzionali psicolinguistici e la generazione delle disfluenze nei balbuzienti

There are two types of studies on disfluencies which are considered to be traditional. The first type consists on the individuation and quantification of the cognitive and situational variables that influence the stutterers' linguistic performance. The second concerns the localization of the "loci" of the utterance associated with the stuttering occurrences, and the explanation of these occurrences. The results of these studies, despite their theoretical and methodological deficiences, have long fascinated the researchers that hoped those results would have provide a linguistic explanation of stuttering.
In this paper are exposed the most formal and convincing applications to the study of stuttering of some psycholinguistic models of normal language production, based on the study of speech errors, nonfluencies and self-repairs.Three theories are presented, Wingate (1988), Perkins, Kent & Curlee (1991) and Postma & Kolk (1993). Although they differ one from another in many respects, they share the same basic assumptions about the limited neural capacity processing of phonological informations in stutterers, and about the feelings of loss of control that characterizes the stutterers' experiences with disfluencies. Hence disfluencies seem to be articulatory automatisms generated by an autonomous restart capability of the "articulator component" (Blackmer & Mitton, 1991) that, in the absence of new phonological material, repeat ciclically the last units. Delayed availability of phonological segments is caused by a slowdown of phonological encoding, arising conflict between alternative phonemes. The conflict generates some degree of interference with the conscious access needed to resolve critical choice points in planning, control, and error detection. Abundant stuttering can be seen as deriving from the need to repeatedly repair one's speech program before speech motor execution.