In studies examining regional activity responses to nicotine or smoking, the most common findings are relative increases in activity in the prefrontal cortex (including the dorsolateral prefrontal cortex, and inferior frontal, medial frontal, and orbitofrontal gyri) (Domino et al. 2000b; Rose et al. 2003; Stein et al. 1998), thalamus (Domino et al. 2000a, b; London et al. 1988a, b; Stein et al. 1998; Zubieta et al. 2001), and visual system (Domino et al. 2000a, b; London et al. 1988a, b). Additionally, a Xe 133 inhalation study reported increases in frontal lobe and thalamic blood flow in smokers who smoked a cigarette (Nakamura et al. 2000). The human studies here examined cigarette smokers, while the animal studies here used non-dependent rats, with strong concordance of findings between these sets of studies. Functional brain imaging studies of nicotine or cigarette administration to human nonsmokers have not yet been reported, and would be important for a more complete understanding of the effects of tobacco on brain activity. While this group of studies demonstrates specific regional activation with nicotine or smoking, they also imply
