To assist in clarifying the factors contributing to the reported neurocognitive and neurobiological dysfunction, studies are needed that: Concurrently assess cohorts of males and females ranging from young to older adults.Employ prospective multi-modality neuroimaging studies (i.e., combining brain morphology, biochemistry, perfusion, and metabolism in the same cohort), with particular attention to the brain reward system.Employ comprehensive neurocognitive testing including behavioral measures of impulsivity, decision-making and risk taking [24,195,196].Consider genetic factors (e.g., ApoE genotype, single nucleotide polymorphisms in BDNF, nAChr, DRD2, COMT, glutamate receptors) implicated in the development and maintenance of substance use disorders (see [197–200]). Such an approach would better delineate the extent and magnitude of the neurobiological and neurocognitive consequences of chronic cigarette smoking, the roles of common genetic variations in vulnerability to nicotine dependence and their inter-relationships.Employ prospective serial longitudinal studies to assess changes in neurobiology and neurocognition over extended periods in chronic smokers (e.g., >5 years). Additionally, it is vital to conduct prospective pre-and-post neuroimaging and neurocognitive studies with individuals engaging in smoking cessation programs to determine if smoking-related neurobiological and neurocognitive abnormalities recover with smoking cessation,
