Speech perception in noise: no interaction between working memory and degree of speech degradation

ABSTRACT

Speech recognition in noise (SiN) requires explicit cognitive resources such as working memory capacity (WMC). However, existing evidence on the role of WMC in SiN, especially for young adults with normal hearing, is mixed. This study aimed to systematically evaluate the role of WMC when the degree of speech recognition varied as a consequence of adding background noise of varying intensity levels. Specifically, the objective was to determine whether or not there was an effect of noise level on the recruitment of WMC during speech recognition tasks. Fifty-three young adults (18–37 years) with normal hearing were recruited and their ability to recognize speech in the presence of background noise was measured using sentences and words. Speech-to-noise ratios (SNRs) were varied from +10 to −10 dB SNR in 5 dB steps to manipulate the degree of speech recognition. Listeners’ WMC was also measured using two working memory tasks. A significant positive association between WMC and SiN was found for sentence recognition in noise. However, no significant interaction between WMC and SNR was found for isolated word and sentence recognition tasks. WMC was not found to be a significant predictor of word recognition in noise. These results suggests that for young normal hearing listeners, the recruitment of WMC during sentence recognition, especially in non-informational fluctuating noise, is not modulated by the SNR .

KEYWORDS:

• Speech recognition
• working memory capacity
• background noise
• degraded speech
• language
• listening
• hearing

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethics

The research reported in this paper adheres to basic ethical considerations for protection of human participants. The study was conducted in full compliance with IRB requirements at the Ohio University.

Participants consent

Full consent from participants in the study was obtained.

Additional information

Funding

Gary Neiman research award and a research award from the College of Health Sciences and Professions at Ohio University.