A proof of concept study of SpeechMate for synchronised speech guidance during public speaking and challenging conversations in adults who stutter, adults with apraxia of speech, and typically fluent adults, measuring percentage of disfluent syllables, speech naturalness, usability, and willingness to public speaking
Speech production during public speaking and semi-structured conversation, including developmental stuttering, apraxia of speech, and typically fluent speech.
SpeechMate is an experimental speech support system based on the principle that speaking in unison with an external voice can reduce disfluent syllables in people who stutter. The system combines a mobile application, augmented reality glasses, bone conduction earbuds, adjustable guiding voice, and text adaptation tools. Depending on the task, SpeechMate will provide either visual text support through augmented reality glasses, auditory guidance through bone conduction earbuds, or both. In conditions with auditory guidance, participants will be asked to speak in unison with the guiding voice, either word by word or with a short delay (also known as shadowing). The guiding voice can be slowed by the participant during speech if they anticipate difficulty or need to regain synchrony. Participants will attend one laboratory visit lasting approximately 60 to 90 minutes. They will complete baseline questionnaires, complete the study speaking tasks, select a guiding voice, and complete practice trials before the main experimental conditions. Practice duration will vary according to participant familiarity with the technology and will be recorded. In Experiment 1, adults who stutter will complete a structured public speaking task in two conditions. In baseline Teleprompter Mode, the prepared speech text will be displayed on augmented reality glasses without auditory guidance. In SpeechMate Presentation Mode, the prepared speech text will be displayed on augmented reality glasses while the selected guiding voice is delivered through bone conduction earbuds. Participants will speak in unison with the guiding voice and may slow the audio in real time. Condition order will be randomised and counterbalanced across participants using a pre-generated Latin square schedule. The allocation sequence will be created before recruitment using a computer-generated randomisation list, and participants will be assigned to the next available sequence after enrolment. Adults with apraxia
1. Adults aged 18 to 65 years 2. Able to speak English with sufficient proficiency to complete prepared speaking tasks, semi-structured conversation tasks, and self report questionnaires 3. Normal or corrected to normal hearing and vision 4. Able to provide written informed consent 5. For the stuttering group: identifies as a person who stutters or has a prior diagnosis of developmental stuttering 6. For the typically fluent group: identifies as a typically fluent speaker 7. For the apraxia of speech group: self reported clinical diagnosis of apraxia of speech
1. Uncorrected hearing or vision impairments that would interfere with the study tasks 2. Any medical or neurological condition that would make wearing smart glasses, bone conduction earbuds, or wearable input devices uncomfortable or unsafe 3. A diagnosed speech, language, or neurological disorder other than developmental stuttering or apraxia of speech, such as dysarthria 4. Inability to complete the speaking tasks or questionnaires in English 5. Inability or unwillingness to provide written informed consent