Fetterman J G, MacEwen D
Arizona State University.
J Exp Anal Behav. 1989 Nov;52(3):311-24. doi: 10.1901/jeab.1989.52-311.
Pigeons' short-term memory for fixed-ratio requirements was assessed using a delayed symbolic matching-to-sample procedure. Different choices were reinforced after fixed-ratio 10 and fixed-ratio 40 requirements, and delays of 0, 5, or 20 s were sometimes placed between sample ratios and choice. All birds made disproportionate numbers of responses to the small-ratio choice alternative when delays were interposed between ratios and choice, and this bias increased as a function of delay. Preference for the small fixed-ratio alternative was also observed on "no-sample" trials, during which the choice alternatives were presented without a prior sample ratio. This "choose-small" bias is analogous to results obtained by Spetch and Wilkie (1983) with event duration as the discriminative stimulus. The choose-small bias was attenuated when the houselight was turned on during delays, but overall accuracy was not influenced systematically by the houselight manipulation.
使用延迟符号样本匹配程序评估鸽子对固定比率要求的短期记忆。在固定比率10和固定比率40要求后强化不同的选择，并且有时在样本比率和选择之间设置0、5或20秒的延迟。当在比率和选择之间插入延迟时，所有鸟类对小比率选择选项做出的反应数量不成比例，并且这种偏差随着延迟而增加。在“无样本”试验中也观察到对小固定比率选项的偏好，在此期间选择选项在没有先前样本比率的情况下呈现。这种“选小”偏差类似于斯佩奇和威尔基（1983年）以事件持续时间作为辨别刺激所获得的结果。当在延迟期间打开饲养箱灯时，“选小”偏差减弱，但整体准确性没有受到饲养箱灯操作的系统影响。
