Cahill J F, Baxter M G
Department of Psychology, Harvard University, 906 William James Hall, 33 Kirkland Street, Cambridge, MA 02138, USA.
Eur J Neurosci. 2001 Dec;14(11):1856-64. doi: 10.1046/j.0953-816x.2001.01807.x.
Rats solving a simple spatial discrimination task in a plus maze initially employ a place-learning strategy, then switch to a motor response strategy. The hippocampus is required for the use of a place-learning strategy in this task. Rats with 192 IgG-saporin lesions of the medial septum/vertical limb of the diagonal band (MS/VDB), that selectively removed cholinergic neurons projecting to the hippocampus, were significantly facilitated in acquisition of the spatial discrimination, and switched from place to response strategies just as control rats did. Rats with ibotenic acid lesions of the MS/VDB, that produced cell loss in the MS/VDB but little damage to cholinergic neurons, were significantly impaired in acquiring the spatial discrimination and did not reliably employ either a place or response strategy at any point in training. This suggests that the MS/VDB modulates hippocampal involvement in place learning, but that cholinergic MS/VDB neurons are neither necessary nor sufficient for using a place strategy to solve a spatial discrimination.
在十字迷宫中解决简单空间辨别任务的大鼠最初采用位置学习策略，然后切换到运动反应策略。在这项任务中，使用位置学习策略需要海马体。内侧隔区/斜角带垂直支（MS/VDB）接受192 IgG-皂草素损伤的大鼠，该损伤选择性地去除了投射到海马体的胆碱能神经元，其在空间辨别学习中得到显著促进，并且和对照大鼠一样从位置策略切换到反应策略。MS/VDB接受鹅膏蕈氨酸损伤的大鼠，该损伤导致MS/VDB中的细胞丢失，但对胆碱能神经元的损伤很小，其在获取空间辨别能力方面显著受损，并且在训练的任何阶段都不能可靠地采用位置或反应策略。这表明MS/VDB调节海马体在位置学习中的参与，但胆碱能MS/VDB神经元对于使用位置策略解决空间辨别既不是必需的也不是充分的。
