Yin H, Barnet R C, Miller R R
Department of Psychology, State University of New York--Binghamton 13902-6000.
J Exp Psychol Anim Behav Process. 1994 Oct;20(4):419-28.
Procedures for establishing second-order excitation (conditioned stimulus [CS] 1-unconditioned stimulus [US] trials followed by CS2-CS1 trials) are highly similar to those for Pavlovian conditioned inhibition (CS1-US trials interspersed with CS2-CS1 trials). Conditioned suppression in rats was used to identify the critical operational differences that result in second-order excitation as opposed to Pavlovian inhibition. No, few, or many CS2-CS1 trials were either interspersed with or given after CS1-US trials. CS2 proved excitatory only after few CS2-CS1 trials, either interspersed or sequential (Experiment 1). In contrast, CS2 proved inhibitory on both summation (Experiment 2) and retardation (Experiment 3) tests only after many CS2-CS1 trials, and then only when the excitatory status of CS1 was preserved. Apparently, the critical difference for establishing second-order excitation or Pavlovian inhibition is the number of CS2-CS1 pairings.
建立二级兴奋（条件刺激[CS]1-非条件刺激[US]试验，随后是CS2-CS1试验）的程序与巴甫洛夫条件性抑制（CS1-US试验穿插CS2-CS1试验）的程序高度相似。利用大鼠的条件性抑制来确定导致二级兴奋而非巴甫洛夫抑制的关键操作差异。在CS1-US试验期间穿插或在其之后进行无、少量或多次CS2-CS1试验。仅在少量CS2-CS1试验（穿插或相继进行）之后，CS2才被证明具有兴奋性（实验1）。相比之下，仅在多次CS2-CS1试验之后，且仅当CS1的兴奋状态得以保持时，CS2在总和（实验2）和延缓（实验3）测试中才被证明具有抑制性。显然，建立二级兴奋或巴甫洛夫抑制的关键差异在于CS2-CS1配对的次数。
