Russell Rona, Kirkpatrick Kimberly
University of York, York, United Kingdom.
Behav Processes. 2007 Feb 22;74(2):115-25. doi: 10.1016/j.beproc.2006.08.004. Epub 2006 Aug 23.
Two experiments trained rats to discriminate two or three stimulus durations using a temporal discrimination task. A standard peak shift effect was observed when training was administered with short versus long signals in Experiment 1. Both discrimination accuracy scores and the generalization gradients revealed that shorter intervals were discriminated more accurately, which may be due to the scalar property of timing. In Experiment 2, three signals (short, medium, and long) were associated with three different responses, or two of the intervals were associated with one response (short and long or short and medium) and the other interval with a different response. Here, the short/medium versus long discrimination was learned most readily of the three tasks. The results of both experiments indicated a strong contribution of learning of individual durations combined with scalar generalization gradients, but Experiment 2 indicated that categorical encoding of durations may have also been operating.
两项实验训练大鼠使用时间辨别任务来区分两种或三种刺激持续时间。在实验1中，当用短信号与长信号进行训练时，观察到了标准的峰值转移效应。辨别准确率得分和泛化梯度都表明，较短的间隔被更准确地区分，这可能是由于时间的标量特性。在实验2中，三个信号（短、中、长）与三种不同的反应相关联，或者其中两个间隔与一种反应（短和长或短和中）相关联，另一个间隔与不同的反应相关联。在这里，短/中与长的辨别是这三个任务中最容易学会的。两项实验的结果都表明，对单个持续时间的学习与标量泛化梯度有很大贡献，但实验2表明，持续时间的分类编码可能也在起作用。
