Transcutaneous Auricular Vagus Nerve Stimulation Enhanced Working Memory in Older Adults with Age-Related Hearing Loss

Abstract

Age-related hearing loss (ARHL) is associated with an increased risk of dementia, necessitating early cognitive interventions to prevent further cognitive decline. Despite promising evidence supporting transcutaneous auricular vagus nerve stimulation (taVNS) for mitigating cognitive impairment, its impact on working memory (WM) in older adults with ARHL is unexplored. This study is the first attempt to investigate taVNS effects on WM in the older adults with hearing impairment (HI) and with typical hearing (TH). WM capacity was assessed using n-back tasks, varying by WM domains (verbal and visuo-spatial) and complexity levels (1-back and 2-back). Participants underwent a two-session, within-subjects, randomized crossover, single-blind sham-controlled protocol, receiving 20 minutes of continuous stimulation in the active session, whereas only 30 seconds at the start and end in the sham session. The HI group performed significantly worse than the TH group on the 2-back tasks. Within the HI group, taVNS significantly enhanced performance across all WM domains and complexity levels compared to the sham condition. These findings suggest that taVNS enhances WM in hearing-impaired older adults, underscoring its potential as a clinical intervention for addressing WM challenges associated with ARHL.