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Stimulating the Lip Motor Cortex with Transcranial Magnetic Stimulation
Published on: June 14, 2014
Persistent developmental stuttering as a cortical-subcortical dysfunction: evidence from muscle activation
Claudia Regina Furquim de Andrade1, Fernanda Chiarion Sassi, Fabiola Juste
1Departament of Physiotherapy, Speech-Language and Hearing Sciences and Occupational Therapy, School of Medicine, University of São Paulo, São Paulo, SP, Brazil. clauan@usp.br
Background:
One contemporary view of stuttering posits that speech disfluencies arise from anomalous speech motor control.
Purpose:
To verify the rest muscle tension and speech reaction time of fluent and stuttering adults.
Method:
22 adults, divided in two groups: G1--11 fluent individuals; G2--11 stutterers. Electromyography recordings (inferior orbicularis oris) were collected in two different situations: during rest and in a reaction time activity.
Results:
The groups were significantly different considering rest muscle tension (G2 higher recordings) and did not differ when considering speech reaction time and muscle activity during speech. There was a strong positive correlation between speech reaction time and speech muscle activity for G2--the longer the speech reaction time, the higher the muscle activity during speech.
Conclusion:
In addition to perceptible episodes of speech disfluency, stutterers exhibit anomalies in speech motor output during fluent speech. Correlations with a possible cortical-subcortical disorder are discussed.
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