Sutphin G, Byrne T, Poling A
Western Michigan University, Kalamazoo 49008, USA.
J Exp Anal Behav. 1998 Jan;69(1):17-28. doi: 10.1901/jeab.1998.69-17.
Groups of 8 experimentally naive rats were exposed during 8-hr sessions to resetting delay procedures in which responses on one lever (the reinforcement lever) produced water after a delay of 8, 16, 32, or 64 s. For rats in one condition, responses on a second (no-consequences) lever had no programmed consequences. For rats in another condition, responses on a second (cancellation) lever during a delay initiated by a response on the reinforcement lever prevented delivery of the scheduled reinforcer; responses on the cancellation lever at other times had no programmed consequences. Under both conditions and at all delays, most subjects emitted more responses on the reinforcement lever than did control rats that never received water emitted on either lever. At 8-s delays, both conditions engendered substantially more responding on the reinforcement lever than on the other lever, and performance closely resembled that of immediate-reinforcement controls. At delays of 16 and 32 s, however, there was clear differential responding on the two levers under the cancellation condition but not under the other condition. When the delay was 64 s, differential responding on the two levers did not occur consistently under either condition. These findings provide strong evidence that the behavior of rats is sensitive to consequences delayed by 8, 16, and 32 s, but only equivocal evidence of such sensitivity to consequences delayed 64 s. They also indicate that acquisition depends, in part, on the measure of performance used to index it.
将8只未经实验的大鼠分为一组，在8小时的实验时段内，让它们接受重置延迟程序，其中在一个杠杆（强化杠杆）上的反应会在延迟8、16、32或64秒后产生水。对于一种条件下的大鼠，在第二个（无后果）杠杆上的反应没有设定的后果。对于另一种条件下的大鼠，在强化杠杆上的反应引发延迟期间，在第二个（取消）杠杆上的反应会阻止预定强化物的交付；在其他时间在取消杠杆上的反应没有设定的后果。在这两种条件下以及所有延迟情况下，大多数实验对象在强化杠杆上发出的反应都比从未在任何一个杠杆上获得过水的对照大鼠更多。在8秒延迟时，两种条件下在强化杠杆上产生的反应都比在另一个杠杆上多得多，并且表现与即时强化对照组非常相似。然而，在16秒和32秒延迟时，在取消条件下两个杠杆上有明显的差异反应，而在另一种条件下则没有。当延迟为64秒时，在两种条件下两个杠杆上的差异反应都没有持续出现。这些发现提供了有力的证据，表明大鼠的行为对延迟8、16和32秒的后果敏感，但对于延迟64秒的后果的敏感性证据则不明确。它们还表明，习得部分取决于用于衡量它的表现指标。
