School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff, CF10 3AT, UK.
Physiol Behav. 2010 Nov 2;101(4):403-12. doi: 10.1016/j.physbeh.2010.07.004. Epub 2010 Jul 17.
Current studies examined whether temporary inactivation of the amygdala influenced the learning and/or expression of conditioned flavour preferences and whether interactions between the amygdala and the nucleus accumbens contribute to this learning. Experiments 1A and 1B examined temporary inactivation of the amygdala in rats, by the administration of muscimol through chronically implanted cannulae, given during acquisition and/or expression of flavour preferences based on a sucrose reinforcer. Despite differences in the number of training trials and control procedures, in both of Experiments 1A and 1B inactivation during training attenuated, but did not totally prevent, the acquisition of a preference for the CS+ (conditioned stimulus) flavour over the CS-. Inactivation during testing had no effect on the preference for the CS+. In Experiment 2A rats were given access to a CS+ flavour paired with fructose and a CS- flavour without fructose prior to testing the preference for the CS+ over the CS- in the absence of the reinforcer. In Experiment 2B the same rats were tested for their preference with another set of CS+ and CS- flavours and maltodextrin as the reinforcing solution. Contralateral unilateral lesions of the amygdala and nucleus accumbens attenuated, but did not totally prevent, flavour preference learning based on either fructose or maltodextrin compared to either ipsilateral or sham lesioned animals. These results suggest that the amygdala plays a role in the learning, but not expression, of flavour preferences and that this role is partially dependent on interactions with the nucleus accumbens.
当前的研究考察了杏仁核的暂时失活是否会影响条件味偏好的学习和/或表达，以及杏仁核和伏隔核之间的相互作用是否有助于这种学习。实验 1A 和 1B 通过在基于蔗糖强化物的味觉偏好的获得和/或表达期间，通过慢性植入的套管给予毒蕈碱，检查了大鼠杏仁核的暂时失活。尽管在训练试验的数量和对照程序上存在差异，但在实验 1A 和 1B 中，失活都在训练期间减弱了，但并没有完全阻止对 CS+（条件刺激）风味相对于 CS-（非条件刺激）的偏好的获得。失活在测试期间对 CS+的偏好没有影响。在实验 2A 中，大鼠在测试之前可以接触到与果糖配对的 CS+风味和没有果糖的 CS-风味，以测试 CS+相对于 CS-的偏好，而没有强化物。在实验 2B 中，相同的大鼠使用另一组 CS+和 CS-风味以及麦芽糖糊精作为强化溶液进行偏好测试。与同侧或假损伤动物相比，杏仁核和伏隔核的对侧单侧损伤减弱了，但并没有完全阻止基于果糖或麦芽糖糊精的味觉偏好学习。这些结果表明，杏仁核在味觉偏好的学习中发挥作用，但在表达中不起作用，而这种作用部分依赖于与伏隔核的相互作用。
