Effects of Age and Working Memory Capacity on Speech Recognition Performance in Noise Among Listeners With Normal Hearing.
This study aimed to determine if younger and older listeners with normal hearing who differ on working memory span perform differently on speech recognition tests in noise. Older adults typically exhibit poorer speech recognition scores in noise than younger adults, which is attributed primarily to poorer hearing sensitivity and more limited working memory capacity in older than younger adults.
RESULTS:
Significant effects of age and working memory capacity were observed on the speech recognition measures in noise, but these effects were mediated somewhat by the speech signal. Specifically, main effects of age and working memory were revealed for both words and sentences, but the interaction between the two was significant for sentences only. For these materials, effects of age were observed for listeners in the low working memory groups only. Although all cognitive measures were significantly correlated with speech recognition in noise, working memory span was the most important variable accounting for speech recognition performance.
CONCLUSIONS:
The results indicate that older adults with high working memory capacity are able to capitalize on contextual cues and perform as well as young listeners with high working memory capacity for sentence recognition. The data also suggest that listeners with normal hearing and low working memory capacity are less able to adapt to distortion of speech signals caused by background noise, which requires the allocation of more processing resources to earlier processing stages. These results indicate that both younger and older adults with low working memory capacity and normal hearing are at a disadvantage for recognizing speech in noise.
https://www.ncbi.nlm.nih.gov/pubmed/27232071Hearing With Your Ears, Listening With Your Brain
"Scientists in recent years have grown increasingly aware of the integral role cognition plays in communication, and this awareness has spawned a new field of research called cognitive hearing science. This field examines the way our minds process the auditory signals being sent to the brain, factor in the complexity of what we’re listening to, and adjust to the quality of listening conditions.
The findings from this field hold particular significance for people with hearing impairments, whose inner ears don’t capture complete auditory information for the brain to process. Long-term effects of insufficient bottom-up signal processing may affect what is stored in the brain, sometimes causing a negative cycle; without understanding, knowledge is not updated, which in turn leads to reduced understanding in the future...
A New Model
Recent models of language understanding under adverse or distracting conditions have emphasized the complex interactions among language signal, working memory capacity (WMC) and related executive functions, and episodic and semantic long-term memory (LTM)....
"Hearing aid manufacturers and dispensers must be made aware of the fact that only people with a high WMC will benefit from more advanced signal processing, and that the fitting of hearing aids should be based on more than the person’s auditory perception of speech."
https://www.psychologicalscience.org/ob ... your-brain