Research on the cognitive memory functions of the hippocampal and parahippocampal neurous of the primate.

灵长类动物的颞叶在认知记忆功能中起着不可缺少的作用。它包含两个系统发育上不同的结构，海马旁皮层的颞叶新皮层（根据von Bonin & Bailey的说法是TE区域）和海马。我们一直在提出灵长类视觉记忆系统的假设，其中TE区域被认为是记忆仓库。为了验证这一假设，在猴子执行视觉记忆任务（延迟匹配样本任务，DMS）时，研究人员检测了颞皮层神经元的单个活动。我们发现形状选择神经元在DMS任务的延迟期表现出持续的活动。该活动对记忆的图像信息具有高度选择性，并且与物体的大小、方向、颜色或位置等物理属性无关，表明延迟活动代表了对图像分类感知的短期记忆。此外，这些延迟放电的选择性是通过DMS任务的反复试验而发展起来的。计算机生成的人工图案被用作记忆的刺激物。在训练过程中，神经元联合选择的少数模式往往通过刺激-刺激关联相互关联。因此，这些细胞获得的选择性被认为代表了图像的联想长期记忆。这些观察结果不仅支持所提出的假设，而且还为假定的记忆库的神经表征提供了更具体、更生动的形式。

Primate temporal lobe plays an indispensable role in the cognitive memory functions. It contains two phylogenetically different structures, the temporal neocortex in the parahippocampal cortex (area TE according to von Bonin ＆ Bailey) and the hippocampus. We has been proposing a hypothesis of the primate visual memory system in which the area TE is considered as the memory storehouse. To test this hypothesis, single-unit activities of the temporal cortical neurons were examined while the monkeys were performing a visual memory task (delayed matching-to-sample task, DMS). We found shape-selective neurons that exhibited sustained activity during the delay period of the DMS task. The activity was highly selective for the pictorial information to be memorized and was independent of the physical attributes such as size, orientation, color or position of the object, suggesting that the delay activity represents the short-term memory of the categorized percept of a picture. Moreover, the selectivity of these delay discharges developed through repeated trials of the DMS task. Computer-generated artificial patterns were used as the stimuli to be memorized. The few patterns for which a neuron was conjointly selective were frequently related to each other through stimulus-stimulus association imposed during the course of training. Thus, the selectivity acquired by these cells is suggested to represent the associative long-term memory of pictures. These observations not only support the proposed hypothesis but also give more concrete, vivid shape to the neural representation of the presumed memory storehouse.