Ronald L. Webster

Perceptual evaluation of the speech before and after fluency shaping stuttering therapy

Abstract An often-cited criterion for assessing the effect of a stuttering therapy is the ability of the stutterers to produce normally fluent speech. Many modern stuttering therapies use special techniques that may produce stutter-free speech that does not sound completely normal. The present study investigates this problem in the framework of the Dutch adaptation of the Precision Fluency Shaping Program. Pre-, post-, and 1 2 -year follow-up therapy speech samples of 32 severe stutterers who were treated in a four-week intensive therapy are compared with comparable samples of 20 nonstutterers. For that aim the samples were rated on 14 bipolar scales by groups of about 20 listeners. The results show that the speech of the stutterers in all three conditions differs significantly from the speech of the nonstutterers. The pretherapy speech takes an extreme position on a Distorted Speech dimension, due to the large proportion of disfluencies. The posttherapy speech has extremely low scores on a Dynamics/Prosody dimension, a`1 while the follow-up therapy speech differs from the normal speech on both dimensions, but now the distances are smaller. These results are discussed in relation to the severity of the stuttering problem in the group of treated stutterers. Finally, implications for future research on therapy evaluation are discussed.

Voice Onset Abruptness in Stutterers Before and After Therapy

In most research and clinical work on stuttering, recognition of stuttered speech is accomplished directly by an observer or observers. The observer is the instrument for identifying and quantifying characteristics of stuttered speech. Specific interests and perceptual skills of investigators determine the level of resolution attained in observation. Typically, resolution has ranged from global ratings of stuttering severity (Johnson, Darley and Spriestersbach, 1963), to frequency counts of a few particular types of disfluency (Williams, Darley and Spriestersbach, 1978) to more “molecular” levels in which numerous disfluency types are elaborated (L.M. Webster and Brutten, 1972). In spite of the diversity of events examined by different investigators, it seems clear that the focal features of stuttered speech involve aberrant properties of speech muscle activity, many of which are simply not readily available for direct, unaided human observation.

Fluency Enhancement in Stutterers

Stuttering is a uniquely human communications disorder that occurs in about 1% of the general population (Bloodstein, 1981). It is found approximately four times more often in males than in females (Andrews & Harris, 1964; Bloodstein, 1981). The median age of stuttering onset is 4 years, and approximately 95% of those who stutter will do so by the age of 7 years (Andrews & Harris, 1964). Most children who stutter (in the vicinity of 75%) “outgrow” the problem by the onset of puberty (Andrews & Harris, 1964; Bloodstein, 1981). Stuttering tends to run in families, with first-degree relatives of stutterers being over three times more likely to stutter than persons in the general population (Andrews, Craig, Feyer, Hoddinot, and Neilson, 1983). Observed familial patterns of stuttering can be accounted for by single major locus and multifactorial genetic models (Kidd, 1980). There is no evidence from the controlled study of unselected populations that stutterers are different from non-stutterers on measures of anxiety or neuroticism (Andrews et al., 1983). Some evidence exists suggesting that stutterers exhibit more problems with social adjustment than nonstutterers (Andrews et al., 1983); however, it seems likely that these results can best be explained by viewing stuttering as the antecedent factor (Prins, 1972).

Establishment of Fluent Speech in Stutterers

Stuttering (or stammering, as it is sometimes known) is a distinctive form of behavior involving anomalous movements of laryngeal and vocal tract motor systems during attempts to produce speech. The repetition of sounds, syllables and words, the apparent “sticking” on a sound, and the blockage of voice during attempts to initiate speech are among the more discriminable physical features of stuttering.

Postnatal weight and behavior changes as a function of components of prenatal maternal injection procedures

The experiment evaluated postnatal weight and behavior effects which resulted from components of prenatally administered subcutaneous injections. Pregnant Ss received handling, hypodermic needle insertions, or distilled water injections in one of three trimesters of gestation. Differences in maze learning in offspring were related to differences in weight lost during the experiment. It appeared that differential resistance to conditions of food deprivation served to contaminate the learning data. It was concluded that several previous studies which involved prenatal maternal treatments with various tranquilizers reported learning data which may share in the confounding of resistance to deprivation conditions with maze learning measures.