Changes in Neural Connectivity Underlie Decision Threshold Modulation for Reward Maximization
Changes in Neural Connectivity Underlie Decision Threshold Modulation for Reward Maximization
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DOI：
10.1523/jneurosci.0573-12.2012
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发表时间：
2012-10-24
影响因子：
5.3
通讯作者：
Heekeren, Hauke R.
中科院分区：
文献类型：
--
作者：
Green, Nikos;Biele, Guido P.;Heekeren, Hauke R.
使用神经成像结合计算建模，这项研究表明，决策阈值调制奖励最大化是伴随着皮质纹状体和小脑纹状体脑系统内的有效连接的变化。对知觉决策的研究表明，人们通过积累感官证据来做出决策，直到超过决策阈值。这个阈值可以根据不断变化的情况进行调整，以获得最大的回报。因此，决策需要有效地管理积累的证据量与可用时间量。重要的是，这种决策阈值调制的神经基质是未知的。参与者在相同的持续时间，但不同的奖励时间表块执行知觉决策任务。行为和建模结果表明，人类受试者调整他们的决策阈值，以最大限度地提高净奖励。神经影像学结果表明，决策阈值调制是通过调整皮质纹状体和小脑-纹状体脑系统内的有效连接来实现的，前者负责处理积累的感觉证据，后者负责自动的亚秒级时间处理。在更大程度上调整阈值（并获得更多净奖励）的参与者也表现出更大的有效连接调制。这些结果揭示了一种神经机制，这种机制是决策者适应不断变化的环境以最大化奖励的能力的基础。
Using neuroimaging in combination with computational modeling, this study shows that decision threshold modulation for reward maximization is accompanied by a change in effective connectivity within corticostriatal and cerebellar-striatal brain systems. Research on perceptual decision making suggests that people make decisions by accumulating sensory evidence until a decision threshold is crossed. This threshold can be adjusted to changing circumstances, to maximize rewards. Decision making thus requires effectively managing the amount of accumulated evidence versus the amount of available time. Importantly, the neural substrate of this decision threshold modulation is unknown. Participants performed a perceptual decision-making task in blocks with identical duration but different reward schedules. Behavioral and modeling results indicate that human subjects modulated their decision threshold to maximize net reward. Neuroimaging results indicate that decision threshold modulation was achieved by adjusting effective connectivity within corticostriatal and cerebellar-striatal brain systems, the former being responsible for processing of accumulated sensory evidence and the latter being responsible for automatic, subsecond temporal processing. Participants who adjusted their threshold to a greater extent (and gained more net reward) also showed a greater modulation of effective connectivity. These results reveal a neural mechanism that underlies decision makers' abilities to adjust to changing circumstances to maximize reward.