Gormezano I
Department of Psychology, University of Iowa, Iowa City 52242.
Brain Res Bull. 1994;35(2):183-7. doi: 10.1016/0361-9230(94)90101-5.
We determined MDA's effects on: (a) conditioning of the rabbit's jaw movement response (JMR) (Experiment 1); and (b) nonassociative JMRs and unconditioned JMRs (Experiment 2). Rabbits were administered 3,4-methylenedioxyamphetamine (MDA; 0, 2, or 4 mg/kg) into the marginal ear vein 20-30 min prior to each of 10 daily sessions. Experiment 1 involved 30 daily training trials of 15 tone- and 15 light-conditioned stimuli (CSs) paired with a 1-ml squirt of water, as the unconditioned stimulus (UCS), injected into the oral cavity. The study revealed that MDA impaired conditioned response (CR) acquisition to tone-CS trials while augmenting CRs to light-CSs. In Experiment 2, the animals received 15 tone- and 15 light CS-alone and 30 UCS-alone presentations daily. The study revealed that MDA produced a modest increase in nonassociative responses over days that interacted with CS modality. Accordingly, these nonassociative effects could not account for MDA's influences on CR acquisition. Moreover, MDA's decrementing and enhancing of CRs to tone- and light-CSs, respectively, appears to be attributable to the drug's enhancing or decrementing tone- and light-CS intensity.
我们确定了3,4-亚甲基二氧基苯丙胺（MDA）对以下方面的影响：（a）兔下颌运动反应（JMR）的条件反射（实验1）；以及（b）非联合性JMR和非条件性JMR（实验2）。在为期10天的每日实验环节中，每次实验前20 - 30分钟，给兔子经耳缘静脉注射3,4-亚甲基二氧基苯丙胺（MDA；剂量为0、2或4毫克/千克）。实验1包括30次每日训练试验，其中15次为音调条件刺激（CS），15次为光条件刺激，每次刺激同时伴随向口腔内注射1毫升水作为非条件刺激（UCS）。研究表明，MDA损害了对音调CS试验的条件反应（CR）习得，同时增强了对光CS的CR。在实验2中，动物每天接受15次单独的音调CS和15次单独的光CS，以及30次单独的UCS呈现。研究表明，MDA在数天内使非联合反应适度增加，且这种增加与CS模式相互作用。因此，这些非联合效应无法解释MDA对CR习得的影响。此外，MDA分别降低和增强对音调CS和光CS的CR，这似乎归因于该药物增强或降低了音调CS和光CS的强度。
