The impact of tinnitus on working memory capacity

Objective: To determine if tinnitus was related to working memory (WM) in adults and if tinnitus handicap was related to WM in adults with tinnitus. Design: Two groups, cross-sectional design. Study samples: 76 adults forming a tinnitus group (n = 38) and a control group (n = 38). Each group included 19 adults with normal hearing and 19 adults with hearing loss matched for age, sex and educational backgrounds. All participants completed the visual n-back test; pure tone audiometry (0.125–16 kHz); and the Hospital Anxiety and Depression Scale (HADS). Tinnitus sufferers also completed the Tinnitus Handicap Inventory (THI). Results: For all participants, tinnitus was not related to WM scores when corrected for hearing thresholds, anxiety, and depression. The corrections for best ear high-frequency pure-tone average hearing threshold (BEHFPTA: 10, 12.5, 14 and 16 kHz) were significant. For tinnitus sufferers, THI was related to WM scores in the easiest n-back condition, and BEHFPTA was related to WM scores in the easiest and the hardest n-back condition. Conclusion: Tinnitus was not related to WM scores. Tinnitus handicap was related to some WM scores in tinnitus sufferers. Further investigation of the possible relationship between high-frequency hearing and WM is warranted.