Studer Bettina, Manes Facundo, Humphreys Glyn, Robbins Trevor W, Clark Luke
Department of Psychology Behavioural and Clinical Neuroscience Institute (BCNI), University of Cambridge, Cambridge, UK, Institute of Cognitive Neuroscience, University College London, London WC1N 3AR, UK.
Institute of Cognitive Neurology (INECO), Favaloro University, Buenos Aires, Argentina and.
Cereb Cortex. 2015 Jan;25(1):1-9. doi: 10.1093/cercor/bht197. Epub 2013 Aug 7.
Successful choice under risk requires the integration of information about outcome probabilities and values and implicates a brain network including the ventromedial prefrontal cortex (vmPFC) and posterior parietal cortex (pPAR). Damage to the vmPFC is linked to poor decision-making and increased risk-taking. Electrophysiological and neuroimaging data implicate the pPAR in the processing of reward probability during choice, but the causal contribution of this area has not been established. We compared patients with lesions to the pPAR (n = 13), vmPFC (n = 13), and healthy volunteers (n = 22) on the Roulette Betting Task, a measure of risk-sensitive decision-making. Both lesion groups were impaired in adjusting their bets to the probability of winning. This impairment was correlated with the extent of pPAR, but not vmPFC, damage. In addition, the vmPFC group chose higher bets than healthy controls overall, an effect that correlated with lesion volume in the medial orbitofrontal cortex. Both lesion groups earned fewer points than healthy controls. The groups did not differ on 2 tasks assessing probabilistic reasoning outside of a risk-reward context. Our results demonstrate the causal involvement of both the pPAR and vmPFC in risk-sensitive choice and indicate distinguishable roles of these areas in probability processing and risk appetite.
在风险下做出成功选择需要整合有关结果概率和价值的信息，并涉及一个包括腹内侧前额叶皮层（vmPFC）和顶叶后皮层（pPAR）的脑网络。vmPFC受损与决策能力差和冒险行为增加有关。电生理和神经影像学数据表明pPAR在选择过程中参与奖励概率的处理，但该区域的因果作用尚未确定。我们在轮盘赌博任务（一种风险敏感决策的测量方法）上比较了pPAR损伤患者（n = 13）、vmPFC损伤患者（n = 13）和健康志愿者（n = 22）。两个损伤组在根据获胜概率调整赌注方面均受损。这种损伤与pPAR的损伤程度相关，但与vmPFC的损伤程度无关。此外，vmPFC组总体上比健康对照组选择更高的赌注，这种效应与内侧眶额皮层的损伤体积相关。两个损伤组获得的分数都比健康对照组少。在两项评估风险回报背景之外的概率推理任务上，这些组没有差异。我们的结果证明了pPAR和vmPFC在风险敏感选择中的因果参与，并表明这些区域在概率处理和风险偏好中具有可区分的作用。
