Flory R K, Lickfett G G
J Exp Anal Behav. 1974 Jan;21(1):45-55. doi: 10.1901/jeab.1974.21-45.
Rats bar pressing on a 1-min fixed-interval schedule for 45-mg food pellets became polydipsic when water was concurrently available. They were then exposed to conditions in which each lick on the drinking tube produced a timeout period during which the food-schedule lever was retracted and the fixed-interval timer either did or did not continue to operate. Licks occurring within a timeout period extended its duration. As the duration of the lick-initiated timeout period was increased logarithmically through four values from 10 sec to 80 sec, lick rates as well as water intake rates generally decreased for all three subjects. As timeout duration was progressively increased, the rate of licks occurring in the absense of, but producing, timeouts decreased for all three rats, whereas the rate of licks occurring in the presence of timeout periods remained essentially constant. Water-intake rates and, with one exception, lick rates were suppressed more by timeout periods during which the fixed-interval timer did not continue to operate. These results indicate that lick-contingent timeout from positive reinforcement reduces schedule-induced drinking, and this suppressive effect is greater when the timeout period necessarily increases the interreinforcement interval beyond its minimum duration than when it does not.
在以45毫克食物颗粒为奖励的1分钟固定间隔时间表上按压杠杆的大鼠，当同时有水供应时会出现饮水过量的情况。然后，它们被置于这样的条件下：每次舔饮水管都会产生一个暂停期，在此期间食物奖励时间表的杠杆会缩回，固定间隔定时器可以继续运行，也可以停止运行。在暂停期内的舔舐会延长其持续时间。随着由舔舐引发的暂停期持续时间以对数方式从10秒增加到80秒，经过四个值，三只受试大鼠的舔舐率和水摄入量通常都下降了。随着暂停期持续时间逐渐增加，三只大鼠在没有产生暂停期但会引发暂停期的情况下的舔舐率均下降，而在有暂停期的情况下的舔舐率基本保持不变。水摄入量以及除一个例外的舔舐率，在固定间隔定时器不继续运行的暂停期内受到的抑制更大。这些结果表明，来自正强化的舔舐依赖型暂停会减少由时间表诱导的饮水，并且当暂停期必然会将强化间隔延长到其最短持续时间以上时，这种抑制作用比不会延长时更大。
