Transcranial magnetic stimulation (or TMS for short)

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Of course this had to come from the boffins at MIT. Not entirely sure what it's practical uses are:

"TMS feels like a determined and annoying older sibling repeatedly flicking you in the head. It's easy to imagine the subtleties of subjective experience being lost in the snapping, cracking, and the arm-twitching, that, while involuntary, is easy to misinterpret as sheer exasperation. Ow, quit it! Ow, quit it!

At first I imagine that my arm jerking is just me responding to the annoyance of being thumped on the head. I am, in short, confabulating wildly. Then I lift my arm on my own power, and watch as it continues jump in midair. I am definitely not doing that."

Sounds like a bunch of fun. And then this bit got me a bit worried:

"Focused on a bipolar patient, TMS can also induce massive mania and psychosis. The effect there is also also temporary, although the damage to the person's credit rating, car or goodwill of his neighbor may not be."

Exactly how did they work that out, and how did it pass the University's ethics board?