Relationship between Auditory Temporal Processing and Working Memory

Abstract

The study evaluated the effect of aging on auditory temporal processing, speech perception abilities and working memory and assessed the relationship among them. A total of 30 young adults in the age range of 1 8-30 years and 30 geriatric individuals in the age range of 60 to 70 years with normal hearing sensitivity participated in the study. The study was divided into 3 experiments- Psychoacoustic experiments, Speech perception experiment and working memory measures. Psychoacoustic experiments included temporal processing measures- gap detection thresholds, modulation detection threshold for sinusoidally amplitude modulated noise and duration pattern scores. Speech perception experiment involved assessing speech perception scores for sentences at 20 dB, 15 dB, 10 dB, 5 dB, 0 dB, -5 dB, -10 dB signal to noise ratios. Working memory measures contained digit forward, digit backward and operation span test. The results revealed that the gap detection thresholds and duration pattern scores declined with age whereas, aging did not show an effect on modulation detection thresholds. All the working memory measures digit forward, digit backward and operation span task showed deterioration with age. Speech perception in noise in the geriatric group was comparable to that of adults at favorable SN Rs ( +20, + J 5, +10, +5 dB SNR) but as the SNR became poorer (0, -5, -10 dB SNR) the geriatric group had significant deterioration when compared to adults. Thus, it can be concluded that working memory has a significant influence and relationship with the temporal processing and speech perception in noise.