Stuttering inhibition via altered auditory feedback during scripted telephone conversations

Area of Science:

• Speech and Hearing Sciences
• Neuroscience of Communication Disorders
• Applied Acoustics

Background:

• Overt stuttering can be significantly inhibited by altered auditory feedback (AAF).
• Stuttering inhibition levels vary based on speaking situation and signal presentation.
• Previous research shows binaural DAF and FAF reduce stuttering by ~57% in phone calls.

Purpose of the Study:

• To investigate stuttering frequency using monaural auditory feedback with combined DAF and FAF.
• To compare stuttering reduction with one combination (COMBO-2) versus two combinations (COMBO-4) of DAF and FAF.
• To assess these effects during scripted telephone conversations.

Main Methods:

• Nine adults who stutter participated in scripted telephone calls to 15 businesses.
• Three conditions were tested: baseline (no altered feedback), COMBO-2 (50ms delay, half-octave spectral shift up), and COMBO-4 (200ms delay, half-octave spectral shift down, plus COMBO-2 effects).
• Participants used a headset and microphone while holding a phone receiver.

Main Results:

• Both AAF conditions significantly reduced stuttering by approximately 65%.
• COMBO-4 demonstrated a greater stuttering reduction (74%) compared to COMBO-2 (63%).
• Stuttering reduction was more pronounced with more AAF effects.

Conclusions:

• Findings support previous research on AAF reducing stuttering in phone conversations.
• Increased AAF effects (COMBO-4) led to greater stuttering inhibition, suggesting a continuum of effectiveness.
• Results indicate AAF can be clinically applied via software/apps to help people who stutter manage frequency in challenging speaking situations.