Variability of Electrolaryngeal Speech Intelligibility in Multitalker Babble

Area of Science:

• Speech-Language Pathology
• Biomedical Engineering
• Audiology

Background:

• Laryngectomy often necessitates the use of an electrolarynx (EL) for speech.
• Understanding the intelligibility of EL speech in various acoustic conditions is crucial for effective communication.
• Variability in EL speech intelligibility can impact user confidence and social participation.

Purpose of the Study:

• To quantify the speech intelligibility of electrolarynx (EL) users in quiet versus multitalker babble conditions.
• To investigate the variability of EL speech intelligibility across different EL device types.
• To explore potential correlations between acoustic measures and speech intelligibility.

Main Methods:

• Ten post-laryngectomy electrolarynx (EL) users (five Servox® Digital, five TruTone™) recorded standardized sentences.
• Naïve listeners transcribed recordings in quiet and multitalker babble conditions.
• Speech intelligibility was assessed by the percentage of correctly transcribed keywords.

Main Results:

• Speech intelligibility was significantly higher in quiet (17.9% more keywords correct) compared to multitalker babble.
• Differences in fundamental frequency (F₀) standard deviation and range were noted between EL device types, but not speech intelligibility.
• A moderate positive correlation was found between F₀ standard deviation and intelligibility for TruTone™ users in babble.

Conclusions:

• Electrolarynx (EL) user speech is more intelligible in quiet than in noisy environments.
• Significant variability exists in EL speech intelligibility, warranting further investigation with larger user groups.
• Future research should examine acoustic features, speaker characteristics, and rehabilitation protocols to enhance EL speech intelligibility.