This is at the intersection of several of my interests.
The idea that nicotine improves cognition in schizophrenia is not new and, indeed, several drugs inspired by this idea (nicotinic agonists) are currently in the pipeline for the treatment of ADHD, schizophrenia, and depression. [1]
In this paper, the researchers are focused on a polymorphism in the CHRNA5 gene. Pulling up my 23andme data, this mutation (rs16969968) looks common, listed at 45% of the population. I have one of the "bad" alleles and, personally, use nicotine as a stimulant every once in a while and find it more effective than coffee but less effective than adderall.
If you are interested in this sort of research, I recommend getting part of your genome sequenced with 23andme [2] and then running your data through Promethease [3]. But, remember, don't take anything too seriously -- most of this isn't settled science.
There is also some evidence that nicotine may function as a "nootropic," i.e. a drug that enhances cognition even in the healthy. Nick Bostrom mentions using nicotine and caffeine to aid writing his book Superintelligence.
Contrary to what you might believe, nicotine is probably not all that bad for you, or even that addictive when not used in combination with an MAOI. The best review of this is, as usual, by Gwern. [4]
Finally, I want to mention a few other interesting properties of nicotine:
- The drug seems to more strongly reinforce behaviors done while under the influence of it than it reinforces "taking nicotine" (addiction). This may make it useful for implementing positive habits. e.g. I often chew half a piece of nicotine gum while running in an attempt to solidify my exercise routine.
- One study suggests that, at least in mice, nicotine administration results in long-term upregulation of reward sensitivity. [5]
Huge disclaimer here at the bottom: if this post convinces you to experiment with nicotine, please do not start with vaping. The near-instant reinforcement of inhaling a stimulant makes it much more addictive. Stick with gum, or a tincture. [6]
[1] https://en.wikipedia.org/wiki/Nicotinic_agonist#Current_stat...
[2] https://www.23andme.com/
[3] https://promethease.com/
[4] https://www.gwern.net/Nicotine
[5] http://www.nature.com/npp/journal/v31/n6/full/1300905a.html
[6] https://www.reddit.com/r/Nootropics/comments/3lvkmc/nicotine...