Lydersen T
Fircrest School, 15230 15th Avenue N.E., Seattle, WA 98155, USA.
Behav Processes. 1994 Apr;31(2-3):323-35. doi: 10.1016/0376-6357(94)90017-5.
Rats' lever pressing turned off stimuli associated with various response-independent fixed-time schedules of food delivery and produced a timeout period during which food delivery could not occur. A lever press during timeout turned on the schedule-associated stimuli and reinstated the fixed-time schedule. Every response that produced timeout ended the timing of fixed time intervals; timeout terminating responses started the timing of fixed-time schedules over again. The percentage of session time spent in timeout periods generally increased as the rate of food delivery decreased. When food delivery could not occur, about half of the session time was spent in the stimulus condition formerly associated with timeout. The majority of timeout periods were initiated after 15 seconds or more had lapsed since the last food delivery. When timeout periods could not be produced, lever pressing rates either decreased or were not affected. The rate of food delivery appeared to be a primary determinant of time spent in timeout periods. The results may be inconsistent with interpretations emphasizing escape from aversive aspects of schedules of positive reinforcement.
大鼠按压杠杆可关闭与各种非应答依赖性定时食物递送时间表相关的刺激，并产生一个超时时间段，在此期间食物递送不会发生。在超时期间的一次杠杆按压会开启与时间表相关的刺激，并恢复定时时间表。每次产生超时的反应都会结束固定时间间隔的计时；终止超时的反应会再次开始定时时间表的计时。随着食物递送速率的降低，超时时间段内花费的会话时间百分比通常会增加。当无法进行食物递送时，大约一半的会话时间花在先前与超时相关的刺激条件下。大多数超时时间段是在自上次食物递送后经过15秒或更长时间后开始的。当无法产生超时时间段时，杠杆按压速率要么降低，要么不受影响。食物递送速率似乎是超时时间段内花费时间的主要决定因素。这些结果可能与强调从正强化时间表的厌恶方面逃脱的解释不一致。
