Say it with me: stuttering inhibited.

Area of Science:

• Neuroscience
• Speech-Language Pathology

Background:

• Stuttering is a complex speech disorder affecting fluency.
• External speech cues can modulate speech production.
• Visual speech, or lip movements, provides articulatory information.

Purpose of the Study:

• To investigate the effect of silently mouthed visual speech on fluency in adults who stutter.
• To compare the impact of linguistically equivalent versus linguistically different visual speech.

Main Methods:

• Ten adults who stutter participated in the study.
• Participants recited memorized text under three conditions: no visual speech, linguistically equivalent visual speech, and linguistically different visual speech.
• Stuttering frequency was measured and compared across conditions.

Main Results:

• A 71% reduction in stuttering was observed when participants watched linguistically equivalent visual speech.
• A 35% reduction in stuttering was observed with linguistically different visual speech, compared to no visual speech.
• Visual speech significantly enhanced fluency, with greater effects for linguistically equivalent stimuli.

Conclusions:

• Silently mouthed visual speech can substantially enhance fluency in people who stutter.
• The degree of linguistic equivalence between the visual speech and the intended utterance is crucial for optimal stuttering inhibition.
• Fluency enhancement may occur by complementing the speaker's speech gestures, compensating for internal speech production inconsistencies.