Buffalo B, Gaffan D, Murray E A
University of Oxford, UK.
Q J Exp Psychol B. 1994 Nov;47(4):353-69.
In Experiment 1 (1a and 1b), Rhesus monkeys (Macaca mulatta) learned lists of two-choice visual discriminations in which list position was relevant to discrimination performance. For example, Stimulus A was the rewarded stimulus if it was presented at List Position 1, but was not rewarded if it was presented at any other position in the list; similarly, Stimulus B was rewarded only at List Position 2, and so on. In learning these lists, all animals showed a marked primacy effect. In Experiment 2 (2a and 2b), Rhesus monkeys and Cynomolgus monkeys (M. fascicularis) learned lists of visual discriminations in which each visual stimulus occupied a fixed position in a list, but list position was not relevant to discrimination performance. For example, Stimulus E was always rewarded, and was always presented at List Position 1. To increase the salience of list beginning as a distinctive event, successive presentations of the list were separated by 24-hr intervals. In Experiment 2 there was no primacy effect, however. These results show for the first time that a primacy effect can be obtained in visual discrimination learning by monkeys. Furthermore, they suggest that it is obtained only when list position is relevant to the discrimination learning task.
在实验1（1a和1b）中，恒河猴（猕猴）学习了一系列二选一的视觉辨别任务，其中列表位置与辨别表现相关。例如，如果刺激A出现在列表位置1，它就是奖励刺激，但如果出现在列表中的任何其他位置，则不会得到奖励；同样，刺激B仅在列表位置2时得到奖励，依此类推。在学习这些列表时，所有动物都表现出明显的首因效应。在实验2（2a和2b）中，恒河猴和食蟹猴（食蟹猕猴）学习了一系列视觉辨别任务，其中每个视觉刺激在列表中占据固定位置，但列表位置与辨别表现无关。例如，刺激E总是得到奖励，并且总是出现在列表位置1。为了增加列表开头作为一个独特事件的显著性，列表的连续呈现之间间隔24小时。然而，在实验2中没有首因效应。这些结果首次表明，猴子在视觉辨别学习中可以获得首因效应。此外，它们表明只有当列表位置与辨别学习任务相关时才会获得首因效应。
