Japanese Speech Jamming Gun

Right here is the "SpeechJammer", a piece of equipment that will, once aimed at someone annoyingly chatting, make him shut up simply by playing anything he was saying back to him loudly and with a couple of hundred millisecond delay, which in turn his brain just can't handle.
 "The SpeechJammer, developed at the National Institute of Advanced Industrial Science and Technology in Japan, works because when we speak, we aren't just using our mouths as an "audio out" speaker. We actively listen to what we're saying, and the way we sound dictates how we proceed with our speech. The SpeechJammer screws with that. The "gun" shoots your words back to you, but with a delay of a few hundred milliseconds, which is enough to mess up natural cadence. The effect is called Delayed Auditory Feedback."

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