Neural Networks and Chemical Messengers: Insights into Tobacco Addiction

This study investigates changes in resting-state networks (RSNs) associated with tobacco addiction (TA) and whether these changes reflect alterations in neurotransmitter systems. A total of 90 patients with TA and 46 healthy controls (HCs) matched for age, education, and body mass index undergo functional magnetic resonance imaging (fMRI) scans. Independent component analysis (ICA) is employed to extract RSNs based on a customized network template using the HCP ICA MATCHING toolbox. Additionally, a correlation study is conducted to examine the relationship between changes in functional connectivity (FC) within RSNs and positron emission tomography and single photon emission computed tomography-derived maps, aiming to identify specific neurotransmitter system changes underlying abnormal FC in TA. Compared to HCs, the TA group exhibits decreased FC values in the left precentral gyrus of the sensorimotor network B and in the right calcarine of the visual network B. Furthermore, changes in FC within the visual network B are associated with the 5-hydroxytryptamine system (1a) and opioid receptor system (Kappa) maps. Post-hoc power analysis confirms the adequacy of the sample size, with effect sizes (d) all greater than 0.9, supporting the robustness of the findings. Patients with TA show reduced intranetwork connectivity in the sensorimotor network B and visual network B, which may reflect underlying molecular changes. These findings improve understanding of the neurobiological aspects of TA.