Centre for Cognition and Decision Making, Institute for Cognitive Neuroscience, HSE University, ul. Myasnitskaya 20, 101000, Moscow, Russian Federation.
Amsterdam School of Economics, University of Amsterdam, Amsterdam, The Netherlands.
Sci Rep. 2022 Sep 27;12(1):16115. doi: 10.1038/s41598-022-18529-6.
In this study, we provide causal evidence that the dorsolateral prefrontal cortex (DLPFC) supports the computation of subjective value in choices under risk via its involvement in probability weighting. Following offline continuous theta-burst transcranial magnetic stimulation (cTBS) of the DLPFC subjects (N = 30, mean age 23.6, 56% females) completed a computerized task consisting of 96 binary lottery choice questions presented in random order. Using the hierarchical Bayesian modeling approach, we then estimated the structural parameters of risk preferences (the degree of risk aversion and the curvature of the probability weighting function) and analyzed the obtained posterior distributions to determine the effect of stimulation on model parameters. On a behavioral level, temporary downregulation of the left DLPFC excitability through cTBS decreased the likelihood of choosing an option with higher expected reward while the probability of choosing a riskier lottery did not significantly change. Modeling the stimulation effects on risk preference parameters showed anecdotal evidence as assessed by Bayes factors that probability weighting parameter increased after the left DLPFC TMS compared to sham.
在这项研究中，我们通过涉及概率加权的方式，提供了背外侧前额叶皮层（DLPFC）支持风险下选择中主观价值计算的因果证据。在对 DLPFC 进行离线连续 theta 爆发经颅磁刺激（cTBS）后（N=30，平均年龄 23.6 岁，女性占 56%），受试者完成了一项由 96 个随机呈现的二进制彩票选择问题组成的计算机任务。然后，我们使用分层贝叶斯建模方法，估计了风险偏好的结构参数（风险厌恶程度和概率加权函数的曲率），并分析了获得的后验分布，以确定刺激对模型参数的影响。在行为水平上，通过 cTBS 暂时下调左侧 DLPFC 的兴奋性会降低选择预期奖励更高的选项的可能性，而选择风险更大的彩票的可能性并没有显著改变。通过对风险偏好参数的刺激效应进行建模，贝叶斯因子评估的证据表明，与假刺激相比，左侧 DLPFC-TMS 后概率加权参数增加。
