Well, Duh.

One of the first things I remember learning in teacher school was this: Don't use sarcasm in your classroom. Kids don't get sarcasm. This came as bad news for me, since sarcasm is my primary mode of expression. I should point out at this juncture that the preceding was an example of just the kind of thing that gets me in trouble all the time. I have spent years of my life explaining to others "what I really meant." Sincerely.
And to the credit of the kids in my fourth grade classes, with very few exceptions, they seem to "get" me. "Oh, you're being sarcastic," they say.
"Really?" I reply in mock surprise.
I know that there are plenty of teachers who spend their entire careers relating to their students in a genuine way that I can only aspire to. Or sneer at. It's just not in my nature to spend more than a few moments at a time being sincere. I recognize that my communication with friends and family have suffered as a result. Happily, I maintain just enough earnestness at those moments when I really need it to keep people from giving up on me altogether.
So you must imagine my glee upon hearing that Neurophysiologist Katherine Rankin at the University of California, San Francisco, has also recently discovered that sarcasm plays an important part in human social interaction. People with dementia, or head injuries in that area, often lose the ability to pick up on sarcasm, and so they don't respond in a socially appropriate ways. If this is true, this makes me a sort of social canary in a coalmine. If you're not picking up on my tone, then there's probably something wrong with you.
And you don't have to believe me, but it's science!