Nice of you to say that, but actually there is a science behind it.

http://www.ncbi.nlm.nih.gov/pubmed/12831873

Yes, this is just one example. I'm talking about actual nicotine, NOT cigarettes and their unwanted chemicals.

http://www.sciencedaily.com/releases...0807154735.htm

Here's another example.

I am not a biologist, but from what I understand nicotine indirectly increases dopamine levels in the brain. Possibly similar to the reason amantadine is prescribed for post TBI.