Graves C A, Solomon P R
Behav Neurosci. 1985 Feb;99(1):88-96. doi: 10.1037//0735-7044.99.1.88.
Young (6 months of age) and old (36-60 months) New Zealand albino rabbits underwent classical conditioning of the nictitating membrane response in either a delay conditioning (Experiment 1) or a trace conditioning (Experiment 2) paradigm. There was no difference between old and young animals in acquisition of the conditioned response in the delay paradigm, nor were there any age-related differences in generalization to the tone conditioned stimulus (CS) or in sensitivity to the tone CS or eye shock unconditioned stimulus. In the trace conditioning paradigm, however, old animals acquired the conditioned response significantly more slowly than young rabbits. Because the same stimulus parameters and the same response were used in both experiments, it is unlikely that age-related differences in trace conditioning were due to stimulus sensitivity, motivation, or fatigue. The results are discussed in terms of how brain changes that accompany aging could differentially affect these two types of classical conditioning.
对年轻（6个月大）和年老（36至60个月）的新西兰白化兔进行瞬膜反应的经典条件反射实验，实验范式为延迟条件反射（实验1）或痕迹条件反射（实验2）。在延迟范式中，年老和年轻动物在获得条件反应方面没有差异，在对音调条件刺激（CS）的泛化、对音调CS或眼部电击非条件刺激的敏感性方面也没有与年龄相关的差异。然而，在痕迹条件反射范式中，年老动物获得条件反应的速度明显比年轻兔子慢。由于两个实验使用了相同的刺激参数和相同的反应，痕迹条件反射中与年龄相关的差异不太可能是由刺激敏感性、动机或疲劳导致的。本文根据衰老过程中伴随的大脑变化如何对这两种经典条件反射产生不同影响来讨论这些结果。
