Lawrence Natalia S, Jollant Fabrice, O'Daly Owen, Zelaya Fernando, Phillips Mary L
King's College London, Section of Neuroscience and Emotion, Division of Psychological Medicine and Psychiatry, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK.
Cereb Cortex. 2009 May;19(5):1134-43. doi: 10.1093/cercor/bhn154. Epub 2008 Sep 11.
The Iowa Gambling Task (IGT) assesses decision-making under initially ambiguous conditions. Neuropsychological and neuroimaging data suggest, albeit inconsistently, the involvement of numerous prefrontal cortical regions in task performance. To clarify the contributions of different prefrontal regions, we developed and validated a version of the IGT specifically modified for event-related functional magnetic resonance imaging. General decision-making in healthy males elicited activation in the ventromedial prefrontal cortex. Choices from disadvantageous versus advantageous card decks produced activation in the medial frontal gyrus, lateral orbitofrontal cortex (OFC), and insula. Moreover, activation in these regions, along with the pre-supplementary motor area (pre-SMA) and secondary somatosensory cortex, was positively associated with task performance. Lateral OFC and pre-SMA activation also showed a significant modulation over time, suggesting a role in learning. Striato-thalamic regions responded to wins more than losses. These results both replicate and add to previous findings and help to reconcile inconsistencies in neuropsychological data. They reveal that deciding advantageously under initially ambiguous conditions may require both continuous and dynamic processes involving both the ventral and dorsal prefrontal cortex.
爱荷华赌博任务（IGT）评估在初始模糊条件下的决策。神经心理学和神经影像学数据虽不一致，但表明许多前额叶皮质区域参与任务执行。为了阐明不同前额叶区域的作用，我们开发并验证了一个专门为事件相关功能磁共振成像修改的IGT版本。健康男性的一般决策会引起腹内侧前额叶皮质的激活。从不利与有利牌组中做出的选择会使额内侧回、外侧眶额皮质（OFC）和脑岛激活。此外，这些区域以及补充运动前区（pre-SMA）和次级体感皮质的激活与任务表现呈正相关。外侧OFC和pre-SMA的激活也随时间呈现显著调制，表明在学习中起作用。纹状体 - 丘脑区域对赢的反应比对输的反应更大。这些结果既重复了先前的发现，又有所补充，有助于调和神经心理学数据中的不一致之处。它们揭示了在初始模糊条件下做出有利决策可能需要涉及腹侧和背侧前额叶皮质的连续且动态的过程。
