背侧和腹侧海马体对痕迹和延迟恐惧条件反射的不同贡献。
Differential contribution of dorsal and ventral hippocampus to trace and delay fear conditioning.
作者信息
Esclassan Frederic, Coutureau Etienne, Di Scala Georges, Marchand Alain R
机构信息
Université de Bordeaux, Centre de Neurosciences Intégratives et Cognitives, C.N.R.S. UMR 5228, Talence, France.
出版信息
Hippocampus. 2009 Jan;19(1):33-44. doi: 10.1002/hipo.20473.
Trace conditioning relies on the maintained representation of a stimulus across a trace interval, and may involve a persistent trace of the conditioned stimulus (CS) and/or a contribution of contextual conditioning. The role of hippocampal structures in these two types of conditioning was studied by means of pretraining lesions and reversible inactivation of the hippocampus in rats. Similar levels of conditioning to a tone CS and to the context were obtained with a trace interval of 30 s. Neurotoxic lesions of the whole hippocampus or reversible muscimol inactivation of the ventral hippocampus impaired both contextual and tone freezing in both trace- and delay-conditioned rats. Dorsal hippocampal injections impaired contextual freezing and trace conditioning, but not delay conditioning. No dissociation between trace and contextual conditioning was observed under any of these conditions. Altogether, these data indicate that the ventral and dorsal parts of the hippocampus compute different aspects of trace conditioning, with the ventral hippocampus being involved in fear and anxiety processes, and the dorsal hippocampus in the temporal and contextual aspects of event representation.
痕迹条件反射依赖于在痕迹间隔期间对刺激的持续表征,并且可能涉及条件刺激(CS)的持续痕迹和/或情境条件反射的作用。通过对大鼠进行海马体的预训练损伤和可逆性失活,研究了海马体结构在这两种类型的条件反射中的作用。在30秒的痕迹间隔下,对音调CS和情境的条件反射水平相似。整个海马体的神经毒性损伤或腹侧海马体的可逆性蝇蕈醇失活会损害痕迹条件反射和延迟条件反射大鼠的情境和音调冻结。背侧海马体注射会损害情境冻结和痕迹条件反射,但不会损害延迟条件反射。在这些条件下均未观察到痕迹条件反射和情境条件反射之间的分离。总之,这些数据表明,海马体的腹侧和背侧部分计算痕迹条件反射的不同方面,腹侧海马体参与恐惧和焦虑过程,而背侧海马体参与事件表征的时间和情境方面。