Toward measuring how well hearing-impaired children speak

Area of Science:

• Audiology
• Speech-Language Pathology
• Linguistics

Background:

• Hearing impairment significantly impacts speech intelligibility.
• Acoustic measures of speech production are crucial for understanding intelligibility.
• Previous research has explored correlations between speech variables and intelligibility.

Purpose of the Study:

• To identify acoustic speech variables that predict intelligibility in hearing-impaired adolescents.
• To compare the predictive power of acoustic variables with pure-tone audiometric thresholds.
• To validate the reliability of predictive acoustic measures.

Main Methods:

• Collected intelligibility scores from 67 hearing-impaired and 2 normally hearing adolescents.
• Measured nine acoustic speech variables (consonant, vowel production, prosody).
• Used regression analysis to determine correlations between speech variables and intelligibility scores.

Main Results:

• Three speech variables showed a multiple correlation of 0.85 with intelligibility.
• Voice-onset-time and second-formant differences accounted for 70% of intelligibility variance.
• Predicted intelligibility scores for a second group showed a high correlation (0.86) with measured scores.
• Five acoustic variables correlated more highly with intelligibility than pure-tone audiometry.

Conclusions:

• Acoustic analysis of speech production provides reliable predictors of intelligibility in hearing-impaired adolescents.
• Specific acoustic features, such as voice-onset-time and formant differences, are critical.
• Acoustic measures offer a more sensitive assessment of speech intelligibility than pure-tone audiometry alone.