Consequences of suppressing thoughts about tinnitus and the effects of cognitive distraction on brain activity in tinnitus patients.

Tinnitus is the perception of sound in the absence of any appropriate external stimulus. Based on the clinical observation that tinnitus patients may distract themselves from their sounds, we performed an experimental test on the effects of suppressing thoughts about tinnitus with 45 tinnitus patients, to systematically evaluate the immediate consequences of suppressing thought vs. attending to tinnitus. Suppression instructions tended to lead to a subsequent decrease in tinnitus-related thoughts, whereas attention to tinnitus resulted in an increase in such thoughts. No effects were seen in a control group who neither suppressed nor attended to their tinnitus. In an independent positron emission tomography study of cerebral blood flow with 8 patients we found that silent backward counting ('serial sevens test') led to a decrease in neural activity in auditory cortex, as well as perceived decrease of tinnitus loudness and annoyance. Thus, distraction that altered the tinnitus experience seemed to attenuate auditory cortex activity. Copyright 2006 S. Karger AG, Basel.