Department of Psychology, University of Kentucky.
J Comp Psychol. 2023 Aug;137(3):148-154. doi: 10.1037/com0000337.
In a successive delay-discounting task, a small reward can be obtained immediately but a larger reward can be obtained if one waits. There is evidence that the larger reward can be obtained more easily if one is "distracted" from obtaining the small reward. It is proposed here that a distractor stimulus may function as a Pavlovian conditioned stimulus (sign tracking) because orienting to it may be directly associated with the larger reinforcer. In the present study with pigeons, we examined two successive procedures: (a) a peck to a red light resulted in one pellet of food, and waiting for the red light to turn off resulted in five pellets (Red-Only). (b) If the pigeon pecked a red light, it received one pellet of food, and if it waited for the red light to turn to green, a peck to the green light resulted in five pellets of food (Red-Green). For both groups, on some trials, a concurrent (distractor) stimulus appeared with the red light but responses to it had no programed consequence. Results indicated that the pigeons in both groups waited for the larger reward more often when the distractor was present than when it was absent and that pigeons in the Red-Only group waited longer than those in the Red-Green group. The results are consistent with the hypothesis that the concurrent stimulus served as a conditioned stimulus for the Red-Only group and as a higher order conditioned stimulus for the Red-Green group. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
在连续的延迟折扣任务中，立即可以获得小奖励，但如果等待，可以获得更大的奖励。有证据表明，如果一个人被“分散注意力”而无法获得小奖励，那么更大的奖励就更容易获得。这里提出的是，分心刺激物可能作为一种条件性刺激物（标记跟踪）起作用，因为对它的定向可能与更大的强化物直接相关。在本研究中，我们使用鸽子进行了两项连续的实验：（a）啄红色灯将获得一粒食物，等待红灯关闭将获得五粒食物（仅红灯）。（b）如果鸽子啄红色灯，它将获得一粒食物，而如果它等待红灯变绿，啄绿灯将获得五粒食物（红绿）。对于两组，在某些试验中，同时出现（分心）刺激与红灯一起出现，但对其的反应没有程序后果。结果表明，当分心物存在时，两组鸽子等待更大奖励的次数都比不存在时更多，而仅红灯组的鸽子等待的时间比红绿组的鸽子更长。结果与假设一致，即同时出现的刺激物作为仅红灯组的条件刺激物，作为红绿组的更高阶条件刺激物。（PsycInfo 数据库记录（c）2023 APA，保留所有权利）。
