in connectivity effects are anticipated for cingulated cortex, precuneus, and executive function areas (Pariyadath et al., 2014). Common neural pathways for drug dependence exist, but alcohol and nicotine have different mechanisms of action. While nicotine seems to be able to directly activate dopamine neurons in the ventral tegmental area, alcohol may indirectly produce a similar effect by inhibiting GABAergic receptors (Nestler, 2005). In this sense, we expect to observe both common and different brain connectivity effects in smoking and drinking subjects depending on their similar effects in the reward system, but exerted through different pathways.
