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Almost every expert who talks about tDCS will tell you, “Don’t try this at home.” But a lot of people are starting to do just that. And it’s no wonder, given the parade of amazing results that researchers have reported achieving on subjects in the lab. It seems like you can make people better at just about anything if you just put the electrodes in the right place. To name just a few of the findings:

Applying the electrodes to the prefrontal cortex can improve learning and increase your working memory.

Applying them to the motor cortex can raise your threshold for pain and make you more adept with your nondominant hand.

Position them above the posterior portion of the left perisylvian area (in right-handed people) and they can facilitate language acquisition.

Stimulation of the parietal cortex can improve numerical reasoning.

via tDCS and rTMS: Is brain stimulation safe and effective? – Slate Magazine.