that might further elucidate the interplay between genotype and neural processes in smokers. However, given that large genetic studies often employ crude phenotypes such as smoker versus non-smoker that are so distal from specific neural processes in smokers, we believe that the current study offers a preliminary but compelling addition to the smoking literature. Future work would benefit by more precisely identifying the relationship between nicotine and 5-HT in the brain, possibly by using imaging technology to examine 5-HT activity in the mesolimbic system during affect relevant manipulations.
