Neurochemical Dysfunction in Smokers
Research indicates that chronic smoking can have deleterious effects on brain chemistry. For example, compared to non-smokers, daily smokers have been shown to exhibit lower concentrations of serotonin in the median raphe nuclei and hippocampus at post mortem (Benwell et al., 1990), while in vivo studies using neuroimaging techniques reveal that chronic smokers exhibit alterations in prefrontal glutamate, creatine and N-acetylaspartate (Durazzo et al., 2016), as well as potentially in striatal dopamine (Newberg et al., 2007).
Results of my own work build upon the research described above, by indicating that even non-daily, intermittent smoking has deleterious effects on prefrontal glutamate, creatine, N-acetylaspartate and myo-inositol, and indeed does so to the same extent as daily smoking. Further results provide the first indication that compared to non-smokers, daily smokers exhibit weak in vivo functional connectivity between two of the most pertinent serotonergic brain regions, the median raphe nuclei and the hippocampus, and that this weak connectivity is related to the experiencing of affective tobacco withdrawal symptoms.
My future work aims to determine the functional relevance of chronic smoking-induced neurochemical changes, and whether such changes hinder successful cessation.
Published Work:
Faulkner P, Lucini Paioni S, Kozhuharova P, Lythgoe DJ, Daniju Y, Morgenroth E, Barker H & Allen P (2020) Daily and Intermittent Smoking Decrease Gray Matter Volume and Concentrations of Glutamate, Creatine, Myo-Inositol and N-acetylaspartate in the Prefrontal Cortex Addiction Biology
Faulkner P, Ghahremani DG, Tyndale RF, Hellmann G & London ED (2018) Functional Connectivity of the Raphe Nuclei: Link to Tobacco Withdrawal in Smokers International Journal of Neuropsychopharmacology