Department of Psychology, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
Proc Natl Acad Sci U S A. 2011 Nov 22;108(47):19048-53. doi: 10.1073/pnas.1117189108. Epub 2011 Nov 7.
A great deal of research focuses on how humans and animals learn from trial-and-error interactions with the environment. This research has established the viability of reinforcement learning as a model of behavioral adaptation and neural reward valuation. Error-driven learning is inefficient and dangerous, however. Fortunately, humans learn from nonexperiential sources of information as well. In the present study, we focused on one such form of information, instruction. We recorded event-related potentials as participants performed a probabilistic learning task. In one experiment condition, participants received feedback only about whether their responses were rewarded. In the other condition, they also received instruction about reward probabilities before performing the task. We found that instruction eliminated participants' reliance on feedback as evidenced by their immediate asymptotic performance in the instruction condition. In striking contrast, the feedback-related negativity, an event-related potential component thought to reflect neural reward prediction error, continued to adapt with experience in both conditions. These results show that, whereas instruction may immediately control behavior, certain neural responses must be learned from experience.
大量研究关注人类和动物如何通过与环境的反复互动来学习。这项研究证实了强化学习作为行为适应和神经奖励估值模型的可行性。然而，错误驱动的学习效率低下且危险。幸运的是，人类也可以从非经验信息来源中学习。在本研究中，我们专注于一种这样的信息，即指导。我们记录了参与者在执行概率学习任务时的事件相关电位。在一个实验条件下，参与者仅收到关于他们的反应是否得到奖励的反馈。在另一个条件下，他们在执行任务之前还收到关于奖励概率的指导。我们发现，指导消除了参与者对反馈的依赖，这从他们在指导条件下立即达到渐近表现就可以看出。相比之下，反馈相关负波，一种被认为反映神经奖励预测误差的事件相关电位成分，在两种条件下都继续随着经验而适应。这些结果表明，虽然指导可以立即控制行为，但某些神经反应必须从经验中学习。
