The role of the entorhinal cortex in object recognition memory and spatial memory in the Japanese monkey

一曰：用逆行和顺行方法观察了日本猴内嗅皮层（EC）与海马结构（HF）的联系。EC向齿状回（DG）和CA 1-CA 3区投射较多。DG和CA_1-CA_3区的荧光主要分布在分子层。HF对EC的主要输入来源于海马下托锥体层和CA 1区。投射细胞数CA 1野优于Sub野（上级）。所有这些投影都是地形学组织的; EC的内侧部分与HF的吻侧部分（DG、CA 1-CA 3场和Sub）相连，而EC的外侧部分与尾侧部分相连。这些结果表明，EC有两个主要输出到HF（DG和CA 1字段）和两个主要输入从HF（从CA 1字段和Sub）。第二章：研究了日本猴双侧EC病变对位置延迟匹配（DML）、颜色延迟匹配（DMC）和2箔摄影刺激延迟匹配（DAF）以及横向图案化问题（TPP）的影响。对于DML，仅在再学习中产生轻度损害，而在延迟测试（20、30和40秒）中未观察到损害。延迟）。对于DMC，在再学习或延迟测试（30、60和120秒）中未观察到缺陷。延迟）。对于脑缺血，在长期延迟（15分钟）中产生轻度损害。而在再学习或短期延迟条件下（30，60和120秒），延迟）。在TPP中，EC猴子的学习速度与对照组一样快。这些结果表明，EC可能至少参与了空间学习的保持和对延迟较长（15分钟）的刺激的识别。

1 : Connections of the entorhinal cortex (EC) with the hippocampal formation (HF) were examined using retrograde and anterograde treats in Japanese monkeys. The EC had heavy projection fibers to the dentate gyrus (DG) and CA1-CA3 fields. Those in the DG and CA1-CA3 fields were distributed in the molecular layer. Main inputs from the HF to the EC were originated from the pyramidal layer of the subiculum (Sub) and CA1 field. The CA1 field was superior to the Sub in the number of projection cells. All these projections were topographically organized ; the medial part of the EC was connected with the rostral portion of the HF (the DG, CA1-CA3 fields and Sub), while the lateral part of the EC was with the caudal portion. These results suggest that the EC had two main outputs to the HF (to the DG and CA1 field) and two main inputs from the HF (from the CA1 field and Sub). 2 : Effects of bilateral EC lesions in Japanese monkeys were examined on delayed matching to location (DML), to color (DMC), and to photographic stimuli (DMP) with 2 foils, and transverse patterning problem (TPP). For DML a mild impairment was produced only in relearning, while no impairment was seen in delay test (20, 30 and 40 sec. delays). For DMC, no deficit was seen on relearning or delay test (30, 60 and 120 sec. delays). For DMP, a mild impairment was produced in long-term delay (15 min.) of delay test alone, while no impairment was seen in relearning or short-term delay conditions (30, 60 and 120 sec. delays). In TPP, the EC monkeys learned as quickly as the controls. These results suggest that the EC might be involved at least in retention of spatial learning and recognition of stimuli with longer delay (15 min.).