The Lombard effect associated with Chinese male alaryngeal speech

Abstract

Objective: Alaryngeal speech shows marked reduction in vocal intensity, resulting in reduced intelligibility. Lombard effect, speaking with background noise has been found to boost speakers’ intensity. The study investigated oesophageal (ES), tracheoesophageal (TE) and electrolaryngeal (EL) speech production under quiet and noisy background conditions to determine if the Lombard effect is still present after laryngectomy.

Method: Fifteen laryngeal and thirty-seven alaryngeal speakers who were native speakers of Cantonese were recruited and instructed to read aloud a Cantonese passage under two background conditions: quiet and 100 dB background noise conditions.

Result: Significant increase in vocal intensity was found in all speaker types under the noise condition. In addition, perceived intelligibility ratings provided by naïve Cantonese listeners revealed that the overall intelligibility under noise was improved for TE and laryngeal speakers, but not for ES and EL speakers, when compared with quiet condition.

Discussion and conclusion: Results confirmed that the Lombard effect is still present after total laryngectomy. However, intelligibility may not always be improved with increased vocal loudness. Improved intelligibility was only observed for TE and laryngeal speakers, but not ES and EL speakers. Clinical implications for the use of the Lombard effect in post-laryngectomy speech rehabilitation are discussed.

Keywords:

• alaryngeal
• Cantonese
• Lombard effect

Additional information

Funding

The present work was funded by Education Faculty Research Fund, University of Hong Kong [200007679/024113/10000/400/01] (PI). “A preliminary study of using Cocktail Party Effect to improve esophageal and tracheoesophageal speech” and Small Project Funding, University of Hong Kong [201409176055] (PI). “An acoustic and physiologic study of articulation associated with different types of Cantonese alaryngeal speech”.