Acute Nicotine Gum and Auditory Brain Responses in Adults With Chronic Tinnitus

This study tests whether a single dose of nicotine gum changes brain responses to sounds and the ability to detect target sounds in non-smoking adults with chronic tinnitus. In a double-blind, placebo-controlled, within-subject crossover design, each participant attends two sessions and receives a single 4 mg dose of nicotine polacrilex gum at one session and a flavor-matched placebo gum at the other, in random order. After gum administration, EEG is recorded at rest and during an active auditory oddball task. The primary measures are the P3 brain response (amplitude and latency) and oddball task accuracy and reaction time.

Inclusion Criteria: * Non-smoking adult, defined as fewer than 100 cigarettes in a lifetime and none in the past year, with a Fagerstrom Test for Nicotine Dependence score of 2 or less and a negative urinary cotinine test * Chronic subjective tinnitus of at least 6 months' duration Exclusion Criteria: * Current or recent tobacco or nicotine use * Pregnancy or breastfeeding * Unstable cardiovascular disease * Any condition precluding the psychoacoustic tasks