Dess N K, Soltysik S S
Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles.
Dev Psychobiol. 1989 Apr;22(3):257-69. doi: 10.1002/dev.420220306.
Excitatory and inhibitory classical conditioning were examined in 4-week-old, 8-week-old, and 12-week-old kittens. Conditioned respiratory suppression (CRS) was a measure of conditioned fear. The inhibitory conditioning procedure was designed to model the schedule of events that normally accompanies successful coping behavior: The safety signal predicted the cancellation of shock that would otherwise follow the danger signal, rather than simply the absence of shock. Before training, the stimuli elicited small unconditioned respiratory suppression in the 4-week-old and 8-week-old kittens, but not in the juvenile, 12-week-old kittens. During training, danger signals came to elicit robust CRS after 3-4 sessions (20-30 trials) in every age group. Acquisition of inhibition of CRS was also observed within 2-3 days (20-30 trials). The effectiveness of inhibitory stimuli improved significantly with age. The safety signal also inhibited fear (CRS) elicited by a second danger signal. Thus, the kittens learned inhibition to the safety signal per se, rather than having learned to discriminate some nonreinforced configured cue from the danger signal presented alone.
在4周龄、8周龄和12周龄的小猫中研究了兴奋性和抑制性经典条件反射。条件性呼吸抑制（CRS）是条件性恐惧的一种度量。抑制性条件反射程序旨在模拟通常伴随成功应对行为的事件顺序：安全信号预示着原本会跟随危险信号出现的电击将被取消，而不仅仅是电击的缺失。在训练前，这些刺激在4周龄和8周龄的小猫中引发了轻微的非条件性呼吸抑制，但在12周龄的幼年小猫中未引发。在训练期间，危险信号在每个年龄组经过3 - 4次训练（20 - 30次试验）后开始引发强烈的CRS。在2 - 3天内（20 - 30次试验）也观察到了对CRS抑制的习得。抑制性刺激的有效性随年龄显著提高。安全信号也抑制了由第二个危险信号引发的恐惧（CRS）。因此，小猫学会了对安全信号本身的抑制，而不是学会从单独呈现的危险信号中辨别出一些未强化的配置线索。
