Flores P, Pellón R
Facultad de Psicología, Universidad Nacional de Educación a Distancia, Ciudad Universitaria, Madrid, Spain.
Pharmacol Biochem Behav. 1997 May-Jun;57(1-2):81-7. doi: 10.1016/s0091-3057(96)00131-1.
Food-deprived rats were divided into four groups according to the equal interval and time durations of a multiple fixed-interval, fixed-time schedule (15, 30, 60, and 120 s). Fixed-time components were signaled by a tone and lever withdrawal. d-Amphetamine (0.25-4.0 mg/kg) produced similar dose-dependent reductions in the drinking and licking induced by fixed-interval and fixed-time schedules. These dose-dependent decrements were a function of the interfood interval length. More licks occurred early in the interfood intervals with doses of d-amphetamine. Dose-dependent shifts to the left were observed in the distribution of licking, and there were dose-dependent decreases in the quarter-life, which were a function of fixed-interval and fixed-time lengths. The maximum lick rate within interfood intervals occurred at about the same absolute time in schedules up to 60 s; therefore, the effects of d-amphetamine were not mediated by its effects on temporal discrimination.
将食物剥夺的大鼠按照多重固定间隔、固定时间模式（15、30、60和120秒）的等间隔和持续时间分为四组。固定时间成分由音调提示和杠杆撤回表示。右旋苯丙胺（0.25 - 4.0毫克/千克）对固定间隔和固定时间模式诱导的饮水和舔舐产生了类似的剂量依赖性减少。这些剂量依赖性减少是食物间隔长度的函数。在食物间隔早期，使用右旋苯丙胺剂量时会出现更多的舔舐。在舔舐分布中观察到剂量依赖性向左偏移，并且在四分之一寿命中有剂量依赖性减少，这是固定间隔和固定时间长度的函数。在长达60秒的模式中，食物间隔内的最大舔舐率在大约相同的绝对时间出现；因此，右旋苯丙胺的作用不是由其对时间辨别力的影响介导的。
