Lempert Karolina M, Tricomi Elizabeth
Rutgers University.
J Cogn Neurosci. 2016 Feb;28(2):261-74. doi: 10.1162/jocn_a_00892. Epub 2015 Oct 6.
Whereas positive feedback is both rewarding and informative, negative feedback can be construed as either punishing (because it is indicative of poor performance) or informative (because it may lead to goal attainment). In this neuroimaging experiment, we highlighted the informational value of negative feedback by intermixing trials with and without feedback. When performance feedback is expected, positive feedback triggers an increase in striatal activity, whereas negative feedback elicits a decrease in striatal activity. We predicted that, in contrast, when feedback receipt is unpredictable, the striatal response to negative feedback would increase. Participants performed a paired-associate learning task during fMRI scanning. In one condition ("blocked feedback"), the receipt of feedback was predictable--participants knew whether or not they would receive feedback for their responses. In another condition ("mixed feedback"), the receipt of feedback was unpredictable--on a random 50% of trials, participants received feedback, and they otherwise received no feedback. Negative feedback in the mixed feedback condition elicited more striatal activity than negative feedback in the blocked feedback condition. In contrast, feedback omission evoked more striatal activity when feedback delivery was expected, compared to when it was unpredictable. This pattern emerged from an increase in caudate activity in response to negative feedback in the mixed feedback condition and a decrease in ventral striatal activity in response to no feedback in this condition. These results suggest that, by emphasizing the informational value of negative feedback, an unpredictable feedback context alters the striatal response to negative feedback and to the omission of feedback.
虽然积极反馈既有益又能提供信息，但消极反馈既可以被视为惩罚（因为它表明表现不佳），也可以被视为提供信息（因为它可能导致目标实现）。在这个神经影像学实验中，我们通过混合有反馈和无反馈的试验来突出消极反馈的信息价值。当预期会有表现反馈时，积极反馈会引发纹状体活动增加，而消极反馈则会导致纹状体活动减少。相比之下，我们预测，当反馈的接收不可预测时，纹状体对消极反馈的反应会增强。参与者在功能磁共振成像扫描期间执行配对联想学习任务。在一种条件下（“分组反馈”），反馈的接收是可预测的——参与者知道他们对自己的反应是否会得到反馈。在另一种条件下（“混合反馈”），反馈的接收是不可预测的——在随机50%的试验中，参与者得到反馈，否则他们得不到反馈。混合反馈条件下的消极反馈比分组反馈条件下的消极反馈引发了更多的纹状体活动。相比之下，与不可预测时相比，当预期会有反馈传递时，无反馈会引发更多的纹状体活动。这种模式源于混合反馈条件下对消极反馈的反应中尾状核活动的增加以及在这种条件下对无反馈的反应中腹侧纹状体活动的减少。这些结果表明，通过强调消极反馈的信息价值，不可预测的反馈情境会改变纹状体对消极反馈和无反馈的反应。
