How effective is therapy for childhood stuttering? Dissecting and reinterpreting the evidence in light of spontaneous recovery rates.

BACKGROUND Similar positive results (e.g. immediate decreases in stuttering frequency and a 60-80% recovery rate from stuttering) have been reported for numerous therapeutic protocols for treating childhood stuttering, many of which have been diametrically opposite in their orientations and implementations. For example, Johnson advocated indirect treatments that simply advocated refraining from drawing any negative attention to childhood disfluencies as persistent and chronic stuttering was thought to progress via negative parental reactions to normal disfluencies. In contrast, direct interventionists sought immediately to eliminate stuttered speech patterns by training 'corrected' speech models that usually involved some form of prolonged speech. However, reports from speech and language therapists around North Carolina, USA, suggest much lower recovery rates in the children they treat (i.e. 13.9% over a median therapeutic period of 3 years, which to the present authors is an indicator of therapeutic inefficiency and ineffectiveness). AIMS The discrepancy between these recovery rates calls for a re-examination of the efficacy of stuttering therapy for children, especially in light of recent statements from some therapies suggesting that therapy might be curative in nature. MAIN CONTRIBUTION Spontaneous and complete recovery (removing all overt and covert markers of the pathology) occurs in 60-80% of all children who display incipient stuttering behaviours. As such, it appears that many claims of therapeutic success in children who stutter are confounded by the possibility of spontaneous recovery during the testing and intervention period. Simply put, it is impossible to discriminate between recovery that would occur naturally over time, and what may have been simply accelerated via therapy. Based on stable prevalence rates and the data in the present paper, it is suggested that therapy does little to boost recovery rates from incipient stuttering. Therapy can provide 'inhibitory' symptomatic relief with varying degrees of success with respect to decreasing stuttering severity and the need for continued therapy. However, it must be made clear that curing stuttering is not a likely outcome of therapy, although successful management can decrease the severity of the problem. It is argued that all forms of stuttering inhibition, including those at work during spontaneous recovery, are all mediated by the degree of mirror neuron engagement in the brain. CONCLUSIONS It is proposed that in children who stutter, the best source of relief from stuttering is in the effective and efficient engagement of mirror neurons via methods that best replicate choral speech. In order to induce natural sounding, fluent speech, it is suggested that one uses primarily derivations of choral speech such as altered auditory feedback. Motoric techniques might also be used synergistically to provide supplementary sources of mirror neuron engagement.