Albert M, Ricker S, Bevins R A, Ayres J J
Department of Psychology, Concordia College, Amherst, Massachusetts.
J Exp Psychol Anim Behav Process. 1993 Jul;19(3):255-64.
Conditioned suppression was used with rats to study the effects of extending conditioned stimuli (CSs) before versus after the delivery of unconditioned stimuli. These extensions are termed B and A extensions, respectively. Within-group designs were used to compare the effects of extending CSs when 2-min parts of those CSs were separated by temporal gaps of 6 min versus a separation of no gap. The results were as follows: (a) B extensions weakened conditioning more than did A extensions, with or without gaps; (b) under some conditions, this asymmetrical effect persisted with extended training; (c) gaps between 2-min parts of a B extension had no detectable effect; and (d) under some parameter values, gaps between 2-min parts of an A extension weakened conditioning significantly. These results are better predicted by the Sometimes Opponent-Process model (SOP; A. R. Wagner, 1981) than by the Rescorla-Wagner-Frey-Sears real-time model (J. J. B. Ayres, M. Albert, & J. C. Bombace, 1987).
运用条件性抑制对大鼠进行研究，以探究在给予非条件刺激之前与之后延长条件刺激（CS）所产生的影响。这些延长分别被称为B型延长和A型延长。采用组内设计来比较当CS的2分钟部分被6分钟的时间间隔隔开与无间隔分开时延长CS的效果。结果如下：（a）无论有无间隔，B型延长比A型延长更能削弱条件作用；（b）在某些条件下，这种不对称效应在延长训练后依然存在；（c）B型延长的2分钟部分之间的间隔没有可检测到的影响；（d）在某些参数值下，A型延长的2分钟部分之间的间隔会显著削弱条件作用。与雷斯克拉 - 瓦格纳 - 弗雷 - 西尔斯实时模型（J. J. B. 艾尔斯、M. 阿尔伯特和J. C. 邦巴斯，1987）相比，有时对立过程模型（SOP；A. R. 瓦格纳，1981）能更好地预测这些结果。
