Singh Varsha, Chaudhary Kapil, Kumaran S Senthil, Chandra Sarat, Tripathi Manjari
Psychology, Humanities and Social Sciences, Indian Institute of Technology Delhi, New Delhi, India.
Department of Neurology, Neuroscience Centre, All India Institute of Medical Sciences, New Delhi, India.
Front Psychol. 2020 Apr 21;11:725. doi: 10.3389/fpsyg.2020.00725. eCollection 2020.
The Iowa Gambling Task (IGT) is a decision-making task that preferentially involves the right prefrontal cortex (PFC). However, the performance of the task is driven by two attributes: intertemporal (long vs. short-term) and frequency-based processing of rewards-punishments, and differs over the two phases of uncertainty (early trials) and risk (later trials). Although intertemporal decision making involves the right PFC, the extent of hemispheric specialization in attribute and phase-specific decision making is unknown. Therefore, the current study assessed decision making in a patient with a uni-hemispheric disease, who underwent hemispherotomy surgery, comparing pre-surgical IGT performance (3 days prior to surgery) with post-surgical performance (1 month, and 12 months post-surgery). The patient's pre- and post-surgical IGT performances were analyzed to examine changes in attribute and phase-specific decision making, including the widely reported deck B phenomenon. The results for the two attributes of deck selection at the pre- and post-surgical assessments suggested marked changes in the two IGT phases of risk and uncertainty. Pre-surgery, the patient made more intertemporally disadvantageous choices, and task-progression contributed to it; within 1 month of surgery, intertemporal disadvantageous deck choices were contingent on task progression, after 1 year, disadvantageous choices were independent of task progression. Intertemporal attribute alteration was unresponsive to uncertainty and risk phase. The effect of task progression on frequency attribute remained unchanged before and immediately after the surgery, and preference for infrequent decks was observed only after 1 year. Further, pre and post surgery alteration in frequency attribute was phase-specific: within 1 month of surgery, infrequent deck choices decreased in uncertainty and increased in risk, whereas the reverse was observed after 12 months. Deck B choice increase was in the uncertainty phase. Results are discussed in reference to valence-linked hemispheric specialization and its potential role in attribute and phase-specific IGT decision making.
爱荷华赌博任务（IGT）是一种决策任务，主要涉及右侧前额叶皮质（PFC）。然而，该任务的表现由两个属性驱动：跨期（长期与短期）和基于频率的奖惩处理，并且在不确定性（早期试验）和风险（后期试验）的两个阶段有所不同。尽管跨期决策涉及右侧PFC，但在属性和阶段特异性决策中半球特化的程度尚不清楚。因此，本研究评估了一名患有单半球疾病并接受了大脑半球切除术的患者的决策情况，将手术前（手术前3天）的IGT表现与手术后（手术后1个月和12个月）的表现进行了比较。分析了患者手术前后的IGT表现，以检查属性和阶段特异性决策的变化，包括广泛报道的B组牌现象。手术前后评估中牌组选择的两个属性结果表明，在IGT的风险和不确定性两个阶段有显著变化。手术前，患者做出了更多跨期不利的选择，且任务进展对此有影响；手术后1个月内，跨期不利的牌组选择取决于任务进展，1年后，不利选择与任务进展无关。跨期属性改变对不确定性和风险阶段无反应。手术前后任务进展对频率属性的影响保持不变，仅在1年后观察到对不频繁牌组的偏好。此外，手术前后频率属性的改变是阶段特异性的：手术后1个月内，在不确定性阶段不频繁牌组选择减少，在风险阶段增加，而在12个月后观察到相反情况。B组牌选择的增加发生在不确定性阶段。本文结合效价相关的半球特化及其在属性和阶段特异性IGT决策中的潜在作用对结果进行了讨论。
