Responses of amygdala neurons to positive reward-predicting stimuli depend on background reward (contingency) rather than stimulus-reward pairing (contiguity).
Responses of amygdala neurons to positive reward-predicting stimuli depend on background reward (contingency) rather than stimulus-reward pairing (contiguity).
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DOI：
10.1152/jn.00933.2009
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发表时间：
2010-03
影响因子：
2.5
通讯作者：
Schultz W
中科院分区：
文献类型：
--
作者：
Bermudez MA;Schultz W
对结果的预测构成了知情经济决策的基本机制。当刺激提供的奖励信息比环境背景更多时，它就构成了奖励预测器。奖励预测可以通过两种方式进行操纵，一种是改变与刺激配对的奖励，就像传统的神经生理学研究那样，另一种是在保持刺激-奖励配对不变的情况下改变背景奖励。参与奖励预测的神经元机制也应该对独立于刺激-奖励配对的背景奖励的变化敏感。我们在涉及奖励处理的主要大脑结构——中央和基底外侧杏仁核上测试了这一假设。在2 × 2设计中，我们检查了奖励和非奖励背景对神经元对奖励和非奖励视觉刺激的反应的影响。事实上，对不变奖励刺激的反应在很大程度上取决于杏仁核神经元群体的背景奖励。将背景奖励提高到被奖励刺激的水平会消除这些反应，而降低背景奖励再次恢复这些反应，但刺激-奖励配对没有变化。与背景（负偶然性）相比，这些神经元都没有对预测较少奖励的抑制性刺激做出特异性反应。一小群杏仁核神经元保持刺激反应，而不考虑背景奖励，可能反映了刺激-奖励配对或视觉感觉过程，没有奖励预测。因此，在对背景奖励敏感的情况下，一群杏仁核神经元对阶段性刺激的反应似乎遵循兴奋性奖励预测的全部标准（积极偶然性），而不是反映简单的刺激-奖励配对（连续性）。
Prediction about outcomes constitutes a basic mechanism underlying informed economic decision making. A stimulus constitutes a reward predictor when it provides more information about the reward than the environmental background. Reward prediction can be manipulated in two ways, by varying the reward paired with the stimulus, as done traditionally in neurophysiological studies, and by varying the background reward while holding stimulus-reward pairing constant. Neuronal mechanisms involved in reward prediction should also be sensitive to changes in background reward independently of stimulus-reward pairing. We tested this assumption on a major brain structure involved in reward processing, the central and basolateral amygdala. In a 2 × 2 design, we examined the influence of rewarded and unrewarded backgrounds on neuronal responses to rewarded and unrewarded visual stimuli. Indeed, responses to the unchanged rewarded stimulus depended crucially on background reward in a population of amygdala neurons. Elevating background reward to the level of the rewarded stimulus extinguished these responses, and lowering background reward again reinstated the responses without changes in stimulus-reward pairing. None of these neurons responded specifically to an inhibitory stimulus predicting less reward compared with background (negative contingency). A smaller group of amygdala neurons maintained stimulus responses irrespective of background reward, possibly reflecting stimulus-reward pairing or visual sensory processes without reward prediction. Thus in being sensitive to background reward, the responses of a population of amygdala neurons to phasic stimuli appeared to follow the full criteria for excitatory reward prediction (positive contingency) rather than reflecting simple stimulus-reward pairing (contiguity).
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影响因子：
16.2
作者：
Histed, Mark H.;Pasupathy, Anitha;Miller, Earl K.
通讯作者：
Miller, Earl K.
影响因子：
3.3
作者：
EVERITT, BJ;MORRIS, KA;ROBBINS, TW
通讯作者：
ROBBINS, TW
影响因子：
1.9
作者：
FALLS, WA;DAVIS, M
通讯作者：
DAVIS, M
影响因子：
1.9
作者：
Britten, KH;Newsome, WT;Movshon, JA
通讯作者：
Movshon, JA
DOI：
10.1037/0097-7403.32.3.284
发表时间：
2006-07-01
期刊：
JOURNAL OF EXPERIMENTAL PSYCHOLOGY-ANIMAL BEHAVIOR PROCESSES
影响因子：
--
作者：
Balsam, Peter D.;Fairhurst, Stephen;Gallistel, Charles R.
通讯作者：
Gallistel, Charles R.