Working memory capacity, speech-in-noise recognition, and informational masking: Age-related patterns from 10 to 60 years using the coordinated response measure
Dhananjay Rachana, Devi NeelamegarajanAbstract
Purpose:
This study aimed to investigate the relationship between auditory working memory (WM) and susceptibility to informational masking (IM) across the age range of 10–60 years in Kannada-speaking listeners, using the coordinate response measure (CRM) speech perception.
Materials and Methods:
In this cross-sectional study, 60 individuals stratified into six age groups (10 to <15 years, 15 to <20 years, 20 to <30 years, 30 to <40 years, 40 to <50 years, and 50 to <60 years), with 10 individuals in each, completed the CRM in two-talker, reverse babble, and speech-shaped noise conditions to measure IM. The auditory WM was assessed using forward, backward, and sequencing digit spans, as well as a 2-N back task, using Smriti-Shravan software.
Results:
Results revealed a nonlinear age effect for speech perception and WM, with the lowest levels in the younger and older groups and peaking in young adulthood (20–29 years). While WM correlated significantly with speech perception thresholds, it did not correlate with IM. Notably, unlike raw signal-to-noise ratio-50s in different maskers, derived IM measures showed no significant age-related differences.
Conclusion:
The results support the “maturation-degeneration” hypothesis, signifying a nonlinear trajectory, where speech perception and WM peak in young adulthood (20–29 years) before declining significantly by 50–59 years. Overall, the maturation and degradation of auditory processing abilities and the cognitive system occur alongside each other across the lifespan.