Gilbert Paul E, Kesner Raymond P
Department of Head and Neck Surgery, University of California-San Diego, San Diego, California 92103, USA.
Learn Mem. 2003 Nov-Dec;10(6):525-30. doi: 10.1101/lm.64503.
Rats with perirhinal cortex (PRC), hippocampal, or sham lesions were trained on a successive discrimination go/no-go task to examine recognition memory for an array of visual objects with varying interference among the objects in the array. Rats were trained to recognize a target array consisting of four particular objects that could be presented in any one of four possible configurations to cover baited food wells. If the four target objects were presented, the rat should displace each object to receive food. However, if a novel object replaced any one or more of the target objects, then the rat should withhold its response. The number of novel objects presented on nonrewarded trials varied from one to four. The fewer the number of novel objects in the array, the more interference the array shared with the target array, therefore increasing task difficulty. An increased number of novel objects should result in less interference with the target array and decreased task difficulty. Although accuracy was slightly lower in rats with hippocampal lesions compared with controls, the learning of the groups was not statistically different. In contrast, rats with PRC lesions were significantly impaired in learning compared with both control and hippocampal-lesioned rats. The results suggest that recognition memory for complex visual discriminations is affected by stimulus interference in rodents with PRC damage.
对患有嗅周皮质（PRC）损伤、海马损伤或假损伤的大鼠进行连续辨别式Go/No-Go任务训练，以检验其对一系列视觉物体的识别记忆，这些物体在阵列中存在不同程度的干扰。训练大鼠识别由四个特定物体组成的目标阵列，该阵列可以以四种可能配置中的任何一种呈现，以覆盖放置诱饵的食物槽。如果呈现这四个目标物体，大鼠应移动每个物体以获取食物。然而，如果一个新物体替换了任何一个或多个目标物体，那么大鼠应抑制其反应。在无奖励试验中呈现的新物体数量从一个到四个不等。阵列中新物体的数量越少，该阵列与目标阵列的干扰就越大，从而增加任务难度。新物体数量增加应导致对目标阵列的干扰减少和任务难度降低。虽然与对照组相比，海马损伤大鼠的准确率略低，但两组的学习情况在统计学上没有差异。相比之下，与对照组和海马损伤大鼠相比，PRC损伤大鼠在学习上明显受损。结果表明，在PRC受损的啮齿动物中，复杂视觉辨别的识别记忆受刺激干扰的影响。
