Altered resting state functional connectivity of anterior insula in young smokers

Abstract

The insula has been implicated in cognitive control and craving, all of which are critical to the clinical manifestations of nicotine dependence. However, little evidence exists about the abnormalities in resting state functional connectivity (RSFC) of the insula in young smokers, which might improve our understanding of the neural mechanisms of nicotine dependence. Due to the structural and functional heterogeneity of the insula, the RSFC patterns of both left and right anterior (AI) and posterior insula (PI) were investigated in young smokers and non-smokers. Meanwhile, the relationship was assessed between the neuroimaging findings and clinical information (pack-years, FTND, and craving) as well as cognitive control deficits measured by Stroop task performance. Compared with non-smokers, young smokers showed reduced RSFC between right AI and anterior cingulate cortex (ACC), ventromedial prefrontal cortex (VMPFC), amygdala, left dorsolateral prefrontal cortex, and dorsal striatum. Additionally, left AI showed reduced RSFC with ACC. Both left and right PI network differences were not observed between two groups. Moreover, in young smokers, FTND and incongruent errors in the Stroop task were negatively correlated with the RSFC between AI and ACC. Craving scores showed a significantly negative relationship with the RSFC strength between right AI and left VMPFC. These results provide a more thorough network-level understanding the role of insula in cigarette smoking. The findings provide new insights into the roles of AI-ACC circuit in cognitive control deficits and right AI-VMPFC circuit relevant to the craving of nicotine dependence for young smokers.

Functional network connectivity predicts treatment outcome during treatment of nicotine use disorder

“…Changes in resting state connectivity over 24 hours of abstinence were observed to predict treatment outcomes (Sweitzer et al, 2016), and a variety of studies have shown alterations in brain activity during subjective withdrawal or from satiation to abstinence in NUD (Bi et al, 2016; Cole et al, 2010; Fedota and Stein, 2015; Froeliger et al, 2015; Huang et al, 2014; Lerman et al, 2014; Moran-Santa Maria et al, 2015; Sutherland et al, 2013b; Sweitzer et al, 2016). Out of concern that the FNC values could have a different relationship with clinical outcome, depending on the withdrawal state of the individual at the time the measure was obtained, we felt it important to explore for interactions between FNC values and withdrawal in our outcome prediction models.…”

“…Although one study showed greater rsFC between fronto-parietal cortex and medial (mPFC) in smokers compared to controls (Janes et al, 2012), most studies demonstrate reduced rsFC (Bi et al, 2016; Fedota et al, 2016; Fedota and Stein, 2015; Fedota et al, 2015; Zanchi et al, 2015) or more negative rsFC (anti-correlation, negative coupling) between prefrontal cortical, cingulate, insular, and striatal regions in smokers relative to controls or in individuals with more severe dependence compared to those with less severe dependence (Stoeckel et al, 2016; Yuan et al, 2016). In line with the growing evidence that low rsFC between many of these key regions is a marker of the presence of NUD and/or the degree of dependence severity, high rsFC, especially between insula and dmPFC (Addicott et al, 2015; Janes et al, 2010) or dACC (Janes et al, 2010), and between insula and dlPFC (Janes et al, 2010) predicts better outcomes during treatment.…”

Functional Connectivity of the Raphe Nuclei: Link to Tobacco Withdrawal in Smokers

“…To help clarify the role of serotonin on the relationship between tobacco withdrawal and connectivity of the median raphe nuclei, future studies could examine effects of serotonergic medications on withdrawal symptoms and associated changes in brain function. As the participants were exclusively young smokers with short smoking histories and mild-to-moderate levels of nicotine dependence, as expected from smokers within this age range (e.g., Li et al, 2015; Bi et al, 2017; Faulkner et al, 2017), the results may not be generalizable to the wider population of smokers. Also, the small sample size and uneven gender distribution made it difficult to examine the influence of sex.…”

Quantic Analysis of the Effect of Nicotine on Neurotransmitters

“…NIC modifies the release of NT and their functions. [10,[13][14] NT is a chemical released from a nerve ending. The transmission of a neuron depends on the action of specific NT on specific receptors.…”

“…Researchers have found that GABA can reduce the enjoyable effects of smoking regarding duration and intensity. [17][18] www.wjpr.net [19,14] Acetylcholine is the primary neurotransmitter of the bulbospinal motor neurons, the preganglionic nerve fibers and other CNS neuronal groups. NIC can bind to the same receptors in the brain as the acetylcholine.…”