What is the Sound of One Hand Clapping?

This post requires participation.  It will be brief, and I promise you won't get hurt.  Ok.  Ready?  Look at your hand.  Make sure it's your left hand.  Close it into a fist.  Open your fist and clap your two hands together.  I am not kidding. Seriously, do it.

Now, what if I told you that the sound you just heard was a phantom that didn't actually happen, and that your arm has been paralyzed for five days now?  You would of course say, Travis, you're crazy!  Although I would be obliged to thank you for such a thoughtful diagnosis, I would nonetheless tell you that for some people, this is actually the case.

Anosognosia for hemiplegia (what a mouthful, here's a wiki link) is an ailment of the mind found in stroke patients who, after getting struck by a stroke, can only use one side of their body.  The strange thing about these patients after they recover from the initial injury is that they deny their condition. Even more odd is that, when asked to preform tasks such as the one you just did (my lovely audience of one billion), patients saw their hands clapping and heard the appropriate sound!

I'll leave you with this question: what is 2+2?

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