Effects of smoking status and state on intrinsic connectivity

Abstract Background Smoking behavior during the first 24 hours of a quit attempt is a significant predictor of longer term abstinence, yet little is known about the neurobiology of early tobacco abstinence. Specifically, the effects of acute tobacco deprivation and reinstatement on brain function—particularly at the level of large-scale network dynamics and assessed across the entire brain—remain incompletely understood. To address this gap, this study uses a mixed within- and between-subjects design to assess the effects of smoking status (yes/no smoker) and state (deprived versus satiated) on whole-brain patterns of intrinsic connectivity. Methods Forty-two tobacco smokers participated in resting state fMRI following overnight abstinence (deprived state) and following smoking reinstatement (satiated state, randomized order across participants). Sixty healthy control non-smokers participated in a single resting state scan using the same acquisition parameters. Functional connectivity data were analyzed using both a canonical network-of-interest (NOI) approach and a whole-brain, data driven approach, intrinsic connectivity distribution (ICD). Results NOI-based analyses indicated decreased functional connectivity within frontoparietal and salience networks among smokers relative to nonsmokers, as well as effects of smoking state on default mode connectivity. In addition, ICD analyses identified novel between-group differences in subcortical-cerebellar and cortico-cerebellar networks that were largely smoking state dependent. Conclusions These data demonstrate the importance of considering smoking state and the utility of using both theory- and data-driven analysis approaches. These data provide much needed insight into the functional neurobiology of early abstinence, which may be used in the development of novel treatments.