Contreras-Rodríguez Oren, Albein-Urios Natalia, Vilar-López Raquel, Perales Jose C, Martínez-Gonzalez Jose M, Fernández-Serrano Maria J, Lozano-Rojas Oscar, Clark Luke, Verdejo-García Antonio
Red de Trastornos Adictivos, Universidad de Granada, Spain.
Institute of Neuroscience F. Oloriz, Universidad de Granada, Spain.
Addict Biol. 2016 May;21(3):709-18. doi: 10.1111/adb.12242. Epub 2015 Mar 29.
Neural biomarkers for the active detrimental effects of cocaine dependence (CD) are lacking. Direct comparisons of brain connectivity in cocaine-targeted networks between CD and behavioural addictions (i.e. pathological gambling, PG) may be informative. This study therefore contrasted the resting-state functional connectivity networks of 20 individuals with CD, 19 individuals with PG and 21 healthy individuals (controls). Study groups were assessed to rule out psychiatric co-morbidities (except alcohol abuse and nicotine dependence) and current substance use or gambling (except PG). We first examined global connectivity differences in the corticolimbic reward network and then utilized seed-based analyses to characterize the connectivity of regions displaying between-group differences. We examined the relationships between seed-based connectivity and trait impulsivity and cocaine severity. CD compared with PG displayed increased global functional connectivity in a large-scale ventral corticostriatal network involving the orbitofrontal cortex, caudate, thalamus and amygdala. Seed-based analyses showed that CD compared with PG exhibited enhanced connectivity between the orbitofrontal and subgenual cingulate cortices and between caudate and lateral prefrontal cortex, which are involved in representing the value of decision-making feedback. CD and PG compared with controls showed overlapping connectivity changes between the orbitofrontal and dorsomedial prefrontal cortices and between amygdala and insula, which are involved in stimulus-outcome learning. Orbitofrontal-subgenual cingulate cortical connectivity correlated with impulsivity and caudate/amygdala connectivity correlated with cocaine severity. We conclude that CD is linked to enhanced connectivity in a large-scale ventral corticostriatal-amygdala network that is relevant to decision making and likely to reflect an active cocaine detrimental effect.
目前尚缺乏用于表明可卡因依赖（CD）产生有害作用的神经生物标志物。直接比较CD患者与行为成瘾者（即病态赌博，PG）在可卡因靶向网络中的脑连接情况可能会有所启发。因此，本研究对比了20名CD患者、19名PG患者和21名健康个体（对照组）的静息态功能连接网络。对研究组进行评估以排除精神共病（酒精滥用和尼古丁依赖除外）以及当前的物质使用或赌博行为（PG除外）。我们首先检查了皮质边缘奖赏网络中的整体连接差异，然后利用基于种子点的分析来表征显示组间差异区域的连接情况。我们研究了基于种子点的连接与特质冲动性和可卡因严重程度之间的关系。与PG相比，CD患者在涉及眶额皮质、尾状核、丘脑和杏仁核的大规模腹侧皮质纹状体网络中表现出整体功能连接增加。基于种子点的分析表明，与PG相比，CD患者在眶额皮质和膝下扣带回皮质之间以及尾状核和外侧前额叶皮质之间表现出更强的连接，这些区域参与表征决策反馈的价值。与对照组相比，CD和PG患者在眶额皮质和背内侧前额叶皮质之间以及杏仁核和岛叶之间表现出重叠的连接变化，这些区域参与刺激-结果学习。眶额皮质-膝下扣带回皮质连接与冲动性相关，尾状核/杏仁核连接与可卡因严重程度相关。我们得出结论，CD与大规模腹侧皮质纹状体-杏仁核网络中增强的连接有关，该网络与决策相关，可能反映了可卡因的有害作用。
