So you've rocked out at a summer's worth of heavy metal music festivals, and now you want to know why you still hear feedback.

That ringing or buzzing in the ear is likely a symptom of hearing loss resulting from excessively loud noises. But tinnitus (the perception of a sound without external stimuli) can also accompany infections, earwax buildups, vertigo, large doses of aspirin, and even a tumor on the acoustic nerve. Of course, your phantom buzz might indicate nothing more than aging ears. Experts aren't sure what physiological process creates the noise, only that it chimes in for a number of afflictions.

If you suffer chronic tinnitus, try not thinking about it! Clinical observations suggest that simply focusing on unrelated thoughts can reduce activity in the auditory cortex and lessen the perceived loudness. Oh, and you might skip Ozzfest next year, too.

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