Department of Psychiatry, Oregon Health & Science University, Portland, Oregon, USA.
Department of Psychiatry Anesthesiology and Perioperative Medicine, Oregon Health & Science University, Portland, Oregon, USA.
Alcohol Clin Exp Res (Hoboken). 2023 Apr;47(4):659-667. doi: 10.1111/acer.15032. Epub 2023 Feb 17.
Studies in animals and humans suggest that greater levels of sensation seeking and alcohol use are related to individual differences in drug-induced dopamine release. However, it remains unclear whether drug-induced alterations in the functional synchrony between mesostriatal regions are related to sensation seeking and alcohol use.
In this within-subject masked-design study, 21-year-old participants (n = 34) underwent functional magnetic resonance imaging to measure ventral tegmental area (VTA) resting-state functional connectivity to the striatum after receiving alcohol (target blood alcohol concentration 0.08 g/dL) or placebo. Participants also completed the UPPS-P Impulsive Behavior Scale to assess sensation seeking, the Young Adult Alcohol Consequences Questionnaire, and self-reported patterns of alcohol and drug use.
Voxel-wise analyses within the striatum demonstrated that during the alcohol condition (compared with placebo) young adults had less connectivity between the VTA and bilateral caudate (p < 0.05 corrected). However, young adults exhibiting smaller alcohol-induced decreases or increases in VTA-left caudate connectivity reported greater sensation seeking.
These findings provide novel information about how acute alcohol impacts resting-state connectivity, an effect that may be driven by the complex pre and postsynaptic effects of alcohol on various neurotransmitters including dopamine. Further, alcohol-induced differences in VTA connectivity represent a plausible mechanistic substrate underlying sensation seeking.
动物和人类研究表明，更高水平的感觉寻求和酒精使用与药物引起的多巴胺释放个体差异有关。然而，药物引起的中脑-纹状体区域之间功能同步的改变是否与感觉寻求和酒精使用有关仍不清楚。
在这项基于个体的、有对照的研究中，21 岁的参与者（n=34）接受了功能磁共振成像，以测量接受酒精（目标血液酒精浓度为 0.08g/dL）或安慰剂后腹侧被盖区（VTA）与纹状体的静息状态功能连接。参与者还完成了 UPPS-P 冲动行为量表来评估感觉寻求，青年酒精后果问卷，以及自我报告的酒精和药物使用模式。
在纹状体的体素分析中，与安慰剂相比，年轻人在酒精状态下 VTA 与双侧尾状核之间的连接减少（p<0.05 校正）。然而，VTA-左侧尾状核连接的酒精诱导减少或增加较小的年轻人报告了更高的感觉寻求。
这些发现提供了关于急性酒精如何影响静息状态连接的新信息，这种效应可能是酒精对各种神经递质（包括多巴胺）的复杂前突触和后突触作用驱动的。此外，VTA 连接的酒精诱导差异代表了感觉寻求的一个合理的机制基础。
