Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ, USA.
Hippocampus. 2012 Oct;22(10):2032-44. doi: 10.1002/hipo.22060.
The perirhinal cortex (PRC) is known to play an important role in object recognition. Little is known, however, regarding the activity of PRC neurons during the presentation of stimuli that are commonly used for recognition memory tasks in rodents, that is, three-dimensional objects. Rats in the present study were exposed to three-dimensional objects while they traversed a circular track for food reward. Under some behavioral conditions, the track contained novel objects, familiar objects, or no objects. Approximately 38% of PRC neurons demonstrated "object fields" (a selective increase in firing at the location of one or more objects). Although the rats spent more time exploring the objects when they were novel compared to familiar, indicating successful recognition memory, the proportion of object fields and the firing rates of PRC neurons were not affected by the rats' previous experience with the objects. Together, these data indicate that the activity of PRC cells is powerfully affected by the presence of objects while animals navigate through an environment; but under these conditions, the firing patterns are not altered by the relative novelty of objects during successful object recognition.
海马旁回（PRC）皮层已知在物体识别中发挥重要作用。然而，对于在啮齿动物的识别记忆任务中常用的刺激（即三维物体）呈现期间 PRC 神经元的活动，人们知之甚少。在本研究中，当老鼠在圆形轨道上为食物奖励而穿行时，它们会接触到三维物体。在某些行为条件下，轨道上有新物体、熟悉物体或没有物体。大约 38%的 PRC 神经元表现出“物体场”（在一个或多个物体位置的选择性发射增加）。尽管与熟悉的物体相比，当物体是新的时，老鼠会花更多的时间探索物体，表明成功的识别记忆，但 PRC 神经元的物体场比例和发射率不受老鼠以前对物体的经验影响。总的来说，这些数据表明，当动物在环境中导航时，PRC 细胞的活动会受到物体存在的强烈影响；但在这些条件下，在成功的物体识别过程中，物体的相对新颖性不会改变发射模式。
