Data from: Neural correlates of successful and unsuccessful strategical mechanisms involved in uncertain decision-making

The ability to develop successful long-term strategies in uncertain situations relies on complex neural mechanisms. Although lesion studies have shown some of the mechanisms involved, it is still unknown why some healthy subjects are able to make the right decision whereas others are not. The aim of our study was to investigate neurophysiological differences underlying this ability to develop a successful strategy in a group of healthy subjects playing a monetary card game called the Iowa Gambling Task (IGT). In this task, subjects have to win and earn money by choosing between four decks of cards, two were advantageous in the long term and two disadvantageous. Twenty healthy right-handed subjects performed the IGT while their cerebral activity was recorded by electroencephalography. Based on their behavioral performances, two groups of subjects could clearly be distinguished: one who selected the good decks and thus succeeded in developing a Favorable strategy (9 subjects) and one who remained Undecided (11 subjects). No neural difference was found between each group before the selection of a deck, but in both groups a greater negativity was found emerging from the right superior frontal gyrus 600 ms before a disadvantageous selection. During the processing of the feedback, an attenuation of the P200 and P300 waveforms was found for the Undecided group, and a P300 originating from the medial frontal gyrus was found in response to a loss only in the Favorable group. Our results suggest that undecided subjects are hyposensitive to the valence of the cards during gambling, which affects the feedback processing.

在不确定情境中制定成功长期策略的能力，依赖于复杂的神经机制。尽管损伤研究已揭示部分相关机制，但目前仍不清楚为何部分健康受试者可做出正确决策，其余受试者却无法做到。本研究旨在探究一组参与名为爱荷华赌博任务（Iowa Gambling Task, IGT）的金钱纸牌游戏的健康受试者中，其成功制定策略的能力背后的神经生理学差异。在该任务中，受试者需从四组纸牌中进行选择以赢取金钱，其中两组为长期有利牌组，另外两组为长期不利牌组。20名健康右利手受试者完成IGT的同时，通过脑电图（electroencephalography）记录其脑活动。基于行为表现，可将受试者明确分为两组：一组选择了有利牌组，成功制定了有利策略（共9人）；另一组始终处于犹豫不定状态（共11人）。两组受试者在选择牌组前未观察到神经活动差异，但在做出不利选择前600毫秒，两组均在右侧额上回出现了更强的负向脑电活动。在反馈处理阶段，犹豫不定组的P200与P300波形出现衰减；而仅在有利策略组中，损失诱发的P300活动起源于内侧额回。本研究结果表明，犹豫不定的受试者在赌博过程中对纸牌的效价敏感性较低，这一特征影响了其反馈处理过程。