Working memory compensates for degraded speech coding only when peripheral hearing deteriorates

Evidence

Taken together, the reported results fail to provide evidence that, in acoustically adverse listening situations, WMC (as measured by the Reading-Span test) is a reliable and strong predictor of SiN intelligibility in young listeners with normal hearing. The new data presented here suggest that WMC becomes more important with age, especially in the oldest participants. One possible explanation for this increasing cognitive involvement with age could be the accumulation of age-related deficits in liminary but also supraliminary auditory processing (e.g. sensitivity to temporal-fine-structure and temporal-envelope cues; Füllgrabe 2013 ; Füllgrabe et al. 2015 ), resulting in under-defined and degraded internal representations of the speech signal, calling for WM-based compensatory mechanisms to aid identification and comprehension. — Dijk, Pim van, Physiology, Psychoacoustics and…, 1154

Categorization

Category: Causal Relationships

• XREF: Connects to the reader’s deep-dive into normal hearing cognition — this explains when and why cognitive load only kicks in for degraded representations, the mechanism border between peripheral and central processing.
• QUESTION: The threshold question — at what point of peripheral deficit (hearing level? age?) does WMC switch from irrelevant to predictive? The paper shows it’s not a clean binary.

Related

• Working memory compensates for degraded internal speech representations in aging. (similarity 0.88)
• Young listeners’ working memory stays irrelevant to speech-in-noise even at very difficult signal levels (similarity 0.87)
• Only mismatched speech input triggers effortful working-memory processing. (similarity 0.84)
• Working memory correlates with speech-in-noise performance only in middle-aged and older normal-hearing listeners (similarity 0.83)
• Working-memory capacity predicts speech understanding only in linguistically complex listening tasks (similarity 0.82)
• Higher working-memory capacity predicts better speech-in-noise identification in hearing-impaired listeners (similarity 0.82)
• Audibility alone cannot fully explain hearing-loss speech deficits; aging and cognition also contribute. (similarity 0.82)
• Working-memory and temporal-processing contributions to intelligibility depend on listening conditions. (similarity 0.81)
• Working memory only matters when the listening task is acoustically hard (similarity 0.81)
• Task difficulty alone does not explain why older listeners show the working-memory effect. (similarity 0.80)
• Working memory capacity explains under two percent of speech-in-noise variance in young listeners. (similarity 0.80)
• Working memory storage helps intelligibility while inhibition and vocabulary do not (similarity 0.80)
• Temporal processing aids intelligibility only for clear isolated single words (similarity 0.80)
• Cognitive contributions to speech perception vary by listening situation (similarity 0.80)
• Working-memory storage aids speech intelligibility while vocab and reading do not. (similarity 0.80)