Nasser Helen M, McNally Gavan P
School of Psychology, The University of New South Wales, Sydney, Australia.
Behav Neurosci. 2012 Jun;126(3):404-22. doi: 10.1037/a0028341.
The existence of value coding and salience coding neurons in the mammalian brain, including in habenula and ventral tegmental area, has sparked considerable interest in the interactions that occur between Pavlovian appetitive and aversive conditioning. Here we studied these appetitive-aversive interactions at the behavioral level by assessing the learning that occurs when a Pavlovian appetitive conditioned stimulus (conditional stimulus, CS) serves as a CS for shock in Pavlovian fear conditioning. A Pavlovian appetitive CS was retarded in the rate at which it could be transformed into a fear CS (counterconditioning), but the presence of the appetitive CS augmented fear learning to a concurrently presented neutral CS (superconditioning). Retardation of fear learning was not alleviated by manipulations designed to restore the associability of the appetitive CS before fear conditioning but was alleviated by manipulations designed to increase the aversive quality of the shock unconditioned stimulus (US). These findings are consistent with opponent interactions between the appetitive and aversive motivational systems and provide a behavioral approach for assessing the neural correlates of these appetitive-aversive interactions.
在哺乳动物大脑中，包括缰核和腹侧被盖区在内，存在着价值编码神经元和显著性编码神经元，这引发了人们对经典条件性食欲和厌恶条件作用之间相互作用的浓厚兴趣。在这里，我们通过评估当经典条件性食欲条件刺激（条件刺激，CS）在经典恐惧条件作用中作为电击的CS时所发生的学习，在行为水平上研究了这些食欲-厌恶相互作用。经典条件性食欲CS转化为恐惧CS（逆向条件作用）的速度受到了阻碍，但是食欲CS的存在增强了对同时呈现的中性CS的恐惧学习（超条件作用）。旨在恢复食欲CS在恐惧条件作用前的关联性的操作并不能减轻恐惧学习的延迟，但旨在增加电击非条件刺激（US）厌恶性质的操作则可以减轻这种延迟。这些发现与食欲和厌恶动机系统之间的对抗性相互作用相一致，并为评估这些食欲-厌恶相互作用的神经关联提供了一种行为学方法。
