راهکارهای درمانی خاص در درمان لکنت زبان کلینیک تخصصی لکنت کرج بلوار ملاصدرا- خیابان ابوذر شمالی
distinguish between a rise in disfluency and a rise in stuttering. Also where these techniques formed the basis of a fluency therapy program, there has been a noticeable difficulty in establishing the new controlled levels of fluency outside the laboratory. In many cases, stuttering that had responded to operant procedures returned to baseline levels immediately following the withdrawal of the given stimulus-response relationship, even when operant techniques such as token reinforcement were used. In addition, while many experiments have shown that stuttering can be brought under operant control to some degree, stuttering has very rarely been totally extinguished during these experiments.
Additionally, not all research has supported the operant case. Martin and Siegel (1966) successfully used contingent electric shock to decrease sec¬ondary stuttering, but found that at the same time there was an increase in some primary stuttering (prolongations). Biggs and Sheehan (1969) found stuttering to decrease when the individual was presented with a loud tone, regardless of whether the noise was presented together with a moment of stuttering, presented randomly or even withdrawn at a moment of stutter¬ing. There are also a number of replication studies which have failed to corroborate the notion that stuttering is an operant condition. Timmons (1966) found no difference in levels of stuttering between two groups of people who stutter, only one of which received response contingent stimuli in the form of the word “wrong”. Similarly, a number of studies (Cady & Robbins, 1968; Cooper, Cady, & Robbins, 1970; Daly & Kimbarrow, 1978) found that positive and neutral verbal contingencies elicited similar decrease in stuttering as did negative verbal stimuli. Similarly, Stevens (1963) and Daly and Cooper (1967) found stuttering failed to respond to electric shock contingencies. Adams and Popelka (1971) found that most
Table 6.1 Summary of early research supporting stuttering as an operant disorder
Researcher Contingent stimulus Findings
Flanagan, Goldiamond, & Azrin (1958) Loud noise Stuttering increased and decreased