The study investigated the effects of music with high arousal potential and negative affect (HA), music with low arousal potential and positive affect (LA), and everyday noise, on the cognitive task performance of introverts and extraverts. Forty participants completed five cognitive tasks: immediate recall, free recall, numerical and delayed recall, and Stroop. Ten participants completed each of these tasks in one of four sound conditions: HA, LA, everyday noise and silence. Participants were also assessed for levels of introversion/ extroversion, and reported their music/noise and study preferences. Performance was lessened across all cognitive tasks in the presence of background sound (music or noise) compared to silence. HA and LA music produced differential distraction effects, with performance of all tasks being poorer in the presence of HA compared to LA and silence, in the presence of noise than silence across all tasks, and in the presence of noise than LA in three of the four tasks. Performance was moderated by internal arousal, with introverts performing better overall on each task except the Stroop, and appearing to be more detrimentally affected by the presence of HA music and noise. (Contains 3 tables and 3 figures.)