Valyear M D, Chaudhri N
Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, 7141 Sherbrooke Street West, Room SP 244, Montreal, QC, H4B-1R6, Canada.
Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, 7141 Sherbrooke Street West, Room SP 244, Montreal, QC, H4B-1R6, Canada.
Behav Processes. 2020 Apr;173:104061. doi: 10.1016/j.beproc.2020.104061. Epub 2020 Feb 1.
Context can influence the number of responses elicited by a discrete, appetitive conditioned stimulus (CS) but can context control when a CS elicits a response? To test this fundamental question, we gave male, Long-Evans rats Pavlovian conditioning sessions in which the same auditory conditioned stimulus (CS, 30 s, 15 trials/session) was presented in 2 different physical contexts on alternating days, according to a within-subjects design. In one context, called the early context, alcohol (15 % ethanol, 0.2 ml/trial) was delivered from the onset of the 5 second until the termination of the 10 second of the 30 s CS. In the second late context, alcohol was delivered from the onset of the 25 second until the termination of the 30 second of the same CS. In a comparison of the last session of training, the probability of making a conditioned response during the first four seconds of the CS was significantly higher in the early context than in the late context. This result shows that context can signal when an unconditioned stimulus occurs in relation to a CS and highlights a role for context in controlling precisely timed alcohol-seeking responses.
情境可以影响由离散的、具有奖赏性的条件刺激（CS）引发的反应数量，但情境能否控制CS引发反应的时间呢？为了测试这个基本问题，我们按照被试内设计，让雄性朗-埃文斯大鼠进行巴甫洛夫条件反射实验，在交替的日子里，在两种不同的物理情境中呈现相同的听觉条件刺激（CS，30秒，每次实验15次）。在一种情境中，称为早期情境，从30秒CS的第5秒开始到第10秒结束给予酒精（15%乙醇，每次实验0.2毫升）。在第二种晚期情境中，从同一CS的第25秒开始到第30秒结束给予酒精。在训练的最后一次实验的比较中，CS前四秒内做出条件反应的概率在早期情境中显著高于晚期情境。这一结果表明，情境可以表明无条件刺激相对于CS何时出现，并突出了情境在精确控制定时觅酒反应中的作用。
