Bingman V P, Jones T J
Department of Psychology, Bowling Green State University, Ohio 43403-0228.
J Neurosci. 1994 Nov;14(11 Pt 1):6687-94. doi: 10.1523/JNEUROSCI.14-11-06687.1994.
The hippocampal formation is known to be critical for spatial cognition, for example, regulating the learning of environmental maps. But how is a spatial map learned, and what is the role of the hippocampal formation in the learning process? The sun compass is perhaps the most ubiquitous, naturally occurring spatial orientation mechanism found in the animal kingdom. The sun compass may also serve as a directional reference that supports spatial learning. We report that homing pigeons with hippocampal lesions were unable to use the sun compass to learn the directional location of food in an outdoor, experimental arena. Homing pigeons with lesions of the caudal neostriatum readily learned the same task, and showed appropriately shifted directional responses following a clock-shift manipulation demonstrating that they were indeed using the sun compass to learn the task. Finally, both hippocampal and control lesioned birds quickly learned a procedurally similar task where a color cue identified the location of food in the same experimental arena. The results indicate that hippocampal lesions impair sun compass use in the context of learning. As such, the results support the hypothesis that the importance of the hippocampal formation in spatial cognition may be related to its participation in a neural process in which information from a directional reference, in this case the sun compass, is used to learn the directional relationship among stimuli in space.
已知海马结构对空间认知至关重要，例如，它能调节对环境地图的学习。但是空间地图是如何习得的，海马结构在学习过程中又扮演着什么角色呢？太阳罗盘可能是动物界最普遍存在的自然空间定向机制。太阳罗盘也可能作为一种方向参考来支持空间学习。我们报告称，海马体受损的归巢鸽无法利用太阳罗盘在户外实验场地学习食物的方向位置。尾侧新纹状体受损的归巢鸽能够轻松学会相同任务，并在时钟偏移操作后表现出适当的方向反应偏移，这表明它们确实在利用太阳罗盘学习任务。最后，海马体受损和对照组受损的鸟类都能很快学会一项程序上类似的任务，即在同一实验场地中，用颜色线索来确定食物的位置。结果表明，海马体损伤会损害学习情境下对太阳罗盘的使用。因此，这些结果支持了这样一种假设，即海马结构在空间认知中的重要性可能与其参与一种神经过程有关，在这个过程中，来自方向参考（在这种情况下是太阳罗盘）的信息被用于学习空间中刺激之间的方向关系。
