TY - JOUR
T1 - Cigarette exposure, dependence, and craving are related to insula thickness in young adult smokers
AU - Morales, Angelica M.
AU - Ghahremani, Dara
AU - Kohno, Milky
AU - Hellemann, Gerhard S.
AU - London, Edythe D.
N1 - Funding Information:
The authors declare no conflict of interest. The research described in this article was funded, in part, by a grant from Philip Morris USA to Dr London under UCLA contract (number 20063287). Additional funding was provided by an endowment from the Thomas P and Katherine K Pike Chair in Addiction Studies and a gift from the Marjorie M Greene Trust. AM Morales and M Kohno were supported by institutional training grant T32 DA 024635 and by F31 DA0331-17 and F31 DA033120-02, respectively. None of the sponsors were involved with the design, collection, analysis or interpretation of data, writing the manuscript, or the decision to submit the manuscript for publications. ED London, the principal investigator, takes responsibility for the integrity of the data and the accuracy of the data analysis. All of the authors had full access to all the data in the study.
PY - 2014/7
Y1 - 2014/7
N2 - The age period spanning late adolescence to emergent adulthood is associated with the highest prevalence of cigarette smoking in the United States, and is also a time of continued brain development. Nonetheless, although prior research has shown group differences in brain structure associated with smoking status in adults, few studies have examined how smoking and associated behavioral states relate to brain structure in this age group. Neuroimaging and lesion studies have suggested that the insula, a cortical region that integrates heterogeneous signals about internal states and contributes to executive functions, plays an important role in cigarette smoking behavior. Using high-resolution structural magnetic resonance imaging, we therefore measured cortical thickness of the insula in 18 smokers and 24 nonsmokers between the ages of 16 and 21 years. There were no group differences in insula thickness, but cigarette exposure (pack-years) was negatively associated with thickness in right insula. Cigarette dependence and the urge to smoke were negatively related to cortical thickness in the right ventral anterior insula. Although the results do not demonstrate causation, they do suggest that there are effects of cigarette exposure on brain structure in young smokers, with a relatively short smoking history. It is possible that changes in the brain due to prolonged exposure or to the progression of dependence lead to more extensive structural changes, manifested in the reported group differences between adult smokers and nonsmokers. Structural integrity of the insula may have implications for predicting long-term cigarette smoking and problems with other substance abuse in this population.
AB - The age period spanning late adolescence to emergent adulthood is associated with the highest prevalence of cigarette smoking in the United States, and is also a time of continued brain development. Nonetheless, although prior research has shown group differences in brain structure associated with smoking status in adults, few studies have examined how smoking and associated behavioral states relate to brain structure in this age group. Neuroimaging and lesion studies have suggested that the insula, a cortical region that integrates heterogeneous signals about internal states and contributes to executive functions, plays an important role in cigarette smoking behavior. Using high-resolution structural magnetic resonance imaging, we therefore measured cortical thickness of the insula in 18 smokers and 24 nonsmokers between the ages of 16 and 21 years. There were no group differences in insula thickness, but cigarette exposure (pack-years) was negatively associated with thickness in right insula. Cigarette dependence and the urge to smoke were negatively related to cortical thickness in the right ventral anterior insula. Although the results do not demonstrate causation, they do suggest that there are effects of cigarette exposure on brain structure in young smokers, with a relatively short smoking history. It is possible that changes in the brain due to prolonged exposure or to the progression of dependence lead to more extensive structural changes, manifested in the reported group differences between adult smokers and nonsmokers. Structural integrity of the insula may have implications for predicting long-term cigarette smoking and problems with other substance abuse in this population.
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U2 - 10.1038/npp.2014.48
DO - 10.1038/npp.2014.48
M3 - Article
C2 - 24584328
AN - SCOPUS:84902553229
SN - 0893-133X
VL - 39
SP - 1816
EP - 1822
JO - Neuropsychopharmacology
JF - Neuropsychopharmacology
IS - 8
ER -