Banca Paula, Lange Iris, Worbe Yulia, Howell Nicholas A, Irvine Michael, Harrison Neil A, Moutoussis Michael, Voon Valerie
Department of Psychiatry, University of Cambridge, UK.
PhD Programme in Experimental Biology and Biomedicine, Center for Neuroscience and Cell Biology, University of Coimbra, Portugal.
Addict Biol. 2016 Mar;21(2):504-15. doi: 10.1111/adb.12227. Epub 2015 Feb 11.
The degree to which an individual accumulates evidence prior to making a decision, also known as reflection impulsivity, can be affected in psychiatric disorders. Here, we study decisional impulsivity in binge drinkers, a group at elevated risk for developing alcohol use disorders, comparing two tasks assessing reflection impulsivity and a delay discounting task, hypothesizing impairments in both subtypes of impulsivity. We also assess volumetric correlates of reflection impulsivity focusing on regions previously implicated in functional magnetic resonance imaging studies. Sixty binge drinkers and healthy volunteers were tested using two different information-gathering paradigms: the beads task and the Information Sampling Task (IST). The beads task was analysed using a behavioural approach and a Bayesian model of decision making. Delay discounting was assessed using the Monetary Choice Questionnaire. Regression analyses of primary outcomes were conducted with voxel-based morphometry analyses. Binge drinkers sought less evidence prior to decision in the beads task compared with healthy volunteers in both the behavioural and computational modelling analysis. There were no group differences in the IST or delay discounting task. Greater impulsivity as indexed by lower evidence accumulation in the beads task was associated with smaller dorsolateral prefrontal cortex and inferior parietal volumes. In contrast, greater impulsivity as indexed by lower evidence accumulation in the IST was associated with greater dorsal cingulate and precuneus volumes. Binge drinking is characterized by impaired reflection impulsivity suggesting a deficit in deciding on the basis of future outcomes that are more difficult to represent. These findings emphasize the role of possible therapeutic interventions targeting decision-making deficits.
个体在做决定前积累证据的程度，也被称为反射性冲动，在精神疾病中可能会受到影响。在此，我们研究酗酒者的决策冲动性，这是一组发展为酒精使用障碍风险较高的人群，比较两项评估反射性冲动的任务和一项延迟折扣任务，假设两种冲动亚型均存在损害。我们还评估反射性冲动的体积相关性，重点关注先前在功能磁共振成像研究中涉及的区域。使用两种不同的信息收集范式对60名酗酒者和健康志愿者进行了测试：珠子任务和信息采样任务（IST）。珠子任务采用行为学方法和决策贝叶斯模型进行分析。使用货币选择问卷评估延迟折扣。对主要结果进行回归分析，并结合基于体素的形态学分析。在行为和计算建模分析中，与健康志愿者相比，酗酒者在珠子任务中做决定前寻求的证据更少。在IST或延迟折扣任务中没有组间差异。在珠子任务中，以较低证据积累为指标的更大冲动性与较小的背外侧前额叶皮层和顶下叶体积相关。相比之下，在IST中，以较低证据积累为指标的更大冲动性与更大的背侧扣带回和楔前叶体积相关。酗酒的特征是反射性冲动受损，这表明在基于更难呈现的未来结果做决定方面存在缺陷。这些发现强调了针对决策缺陷的可能治疗干预措施的作用。
