Manohar Sanjay G, Finzi Rebecca Dawn, Drew Daniel, Husain Masud
1 Nuffield Department of Clinical Neurosciences, University of Oxford.
2 Department of Psychology, University of California San Diego.
Psychol Sci. 2017 Jul;28(7):1016-1026. doi: 10.1177/0956797617693326. Epub 2017 May 10.
When rewards are available, people expend more energy, increasing their motivational vigor. In theory, incentives might drive behavior for two distinct reasons: First, they increase expected reward; second, they increase the difference in subjective value between successful and unsuccessful performance, which increases contingency-the degree to which action determines outcome. Previous studies of motivational vigor have never compared these directly. Here, we indexed motivational vigor by measuring the speed of eye movements toward a target after participants heard a cue indicating how outcomes would be determined. Eye movements were faster when the cue indicated that monetary rewards would be contingent on performance than when the cue indicated that rewards would be random. But even when the cue indicated that a reward was guaranteed regardless of speed, movement was still faster than when no reward was available. Motivation by contingent and certain rewards was uncorrelated across individuals, which suggests that there are two separable, independent components of motivation. Contingent motivation generated autonomic arousal, and unlike noncontingent motivation, was effective with penalties as well as rewards.
当有奖励可得时，人们会消耗更多能量，从而增强他们的动机活力。从理论上讲，激励因素可能通过两个不同的原因驱动行为：第一，它们增加了预期奖励；第二，它们增加了成功与不成功表现之间主观价值的差异，这增加了偶然性——即行动决定结果的程度。以往关于动机活力的研究从未直接比较过这些。在此，我们通过测量参与者听到提示表明结果将如何确定后，眼睛向目标移动的速度来衡量动机活力。当提示表明金钱奖励将取决于表现时，眼睛移动速度比提示表明奖励是随机的时更快。但即使提示表明无论速度如何奖励都有保证，移动速度仍然比没有奖励时更快。偶然性奖励和确定性奖励产生的动机在个体之间不相关，这表明动机有两个可分离的、独立的组成部分。偶然性动机产生自主唤醒，并且与非偶然性动机不同，它在惩罚以及奖励方面都有效。
