Have you ever got a song stuck in your head that you just can’t seem to shake? That catchy piece of music on a recurrent loop in your brain, also known as an earworm, may seem torturous but pales in comparison to actual sound torture employed for military purposes. Sound torture is a type of psychological warfare used to break the will of prisoners using loud music or white noise. While many of us use music to escape or even center ourselves, it can also be used as an instrument of torture under the right conditions.
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http://www.medicaldaily.com/torture-methods-sound-how-pure-noise-can-be-used-break-you-psychologically-318638