Audiovisual benefit for recognition of speech presented with single-talker noise in older listeners

Abstract

Older listeners are more affected than younger listeners in their recognition of speech in adverse conditions, such as when they also hear a single-competing speaker. In the present study, we investigated with a speeded response task whether older listeners with various degrees of hearing loss benefit under such conditions from also seeing the speaker they intend to listen to. We also tested, at the same time, whether older adults need postperceptual processing to obtain an audiovisual benefit. When tested in a phoneme-monitoring task with single-talker noise present, older (and younger) listeners detected target phonemes more reliably and more rapidly in meaningful sentences uttered by the target speaker when they also saw the target speaker. This suggests that older adults processed audiovisual speech rapidly and efficiently enough to benefit already during spoken sentence processing. Audiovisual benefits for older adults were similar in size to those observed for younger adults in terms of response latencies, but smaller for detection accuracy. Older adults with more hearing loss showed larger audiovisual benefits. Attentional abilities predicted the size of audiovisual response time benefits in both age groups. Audiovisual benefits were found in both age groups when monitoring for the visually highly distinct phoneme /p/ and when monitoring for the visually less distinct phoneme /k/. Visual speech thus provides segmental information about the target phoneme, but also provides more global contextual information that helps both older and younger adults in this adverse listening situation.

Keywords:

• Speech perception
• Audiovisual
• Aging
• Adverse listening
• Individual differences

Acknowledgements

We thank the student assistants of the MPI Comprehension group for their help with the experiment and Chuck Clifton for constructive comments on an earlier draft. This work was supported in part by Innovational Research Incentive Scheme Veni grants from the Netherlands Organization for Scientific Research awarded to the two authors, respectively. Parts of this work were presented in “Seeing a speaker's face helps stream segregation for younger and elderly adults” Journal of the Acoustical Society of America, 125, 2659, and in “Visual speech information aids elderly adults in stream segregation”, Proceedings of the Auditory-Visual Speech Processing International Conference, Norwich, UK, September 2009, and at the workshop Psycholinguistic Approaches to Speech Recognition in Adverse Conditions, Bristol, March 2010.

Notes

¹The exception to this being one participant who wore hearing aids in his daily life. Phoneme-monitoring results below are reported with data from the three participants who had hearing aids included, but we also report how results would change with these three participants excluded.