Lawrence Andrew D, Brooks David J
School of Psychology, Cardiff University Cardiff, UK.
Division of Brain Sciences, Department of Medicine, Imperial College London, UK ; Department of Nuclear Medicine, PET Centre, Aarhus University Aarhus, Denmark.
Front Behav Neurosci. 2014 Mar 14;8:86. doi: 10.3389/fnbeh.2014.00086. eCollection 2014.
Pathological gambling, alongside addictive and antisocial disorders, forms part of a broad psychopathological spectrum of externalizing disorders, which share an underlying genetic vulnerability. The shared externalizing propensity is a highly heritable, continuously varying trait. Disinhibitory personality traits such as impulsivity and novelty seeking (NS) function as indicators of this broad shared externalizing tendency, which may reflect, at the neurobiological level, variation in the reactivity of dopaminergic (DAergic) brain reward systems centered on the ventral striatum (VS). Here, we examined whether individual differences in ventral striatal dopamine (DA) synthesis capacity were associated with individual variation in disinhibitory personality traits. Twelve healthy male volunteers underwent 6-[(18)F]Fluoro-L-DOPA (FDOPA) positron emission tomography (PET) scanning to measure striatal DA synthesis capacity, and completed a measure of disinhibited personality (NS). We found that levels of ventral, but not dorsal, striatal DA synthesis capacity were significantly correlated with inter-individual variation in disinhibitory personality traits, particularly a propensity for financial extravagance and irresponsibility. Our results are consistent with preclinical models of behavioral disinhibition and addiction proneness, and provide novel insights into the neurobiology of personality based vulnerability to pathological gambling and other externalizing disorders.
病理性赌博与成瘾性和反社会障碍一样，是外化障碍广泛心理病理学谱系的一部分，这些障碍具有共同的潜在遗传易感性。共同的外化倾向是一种高度可遗传的、持续变化的特质。冲动性和寻求新奇（NS）等抑制解除型人格特质是这种广泛共享的外化倾向的指标，在神经生物学层面，这可能反映了以腹侧纹状体（VS）为中心的多巴胺能（DAergic）脑奖赏系统反应性的变化。在此，我们研究了腹侧纹状体多巴胺（DA）合成能力的个体差异是否与抑制解除型人格特质的个体差异相关。12名健康男性志愿者接受了6-[(18)F]氟-L-多巴（FDOPA）正电子发射断层扫描（PET）以测量纹状体DA合成能力，并完成了一项抑制解除型人格（NS）测量。我们发现，腹侧而非背侧纹状体DA合成能力水平与抑制解除型人格特质的个体差异显著相关，尤其是在财务挥霍和不负责任的倾向上。我们的结果与行为抑制解除和成瘾倾向的临床前模型一致，并为基于人格的病理性赌博和其他外化障碍易感性的神经生物学提供了新的见解。
