Mumby Dave G, Tremblay Annie, Lecluse Valerie, Lehmann Hugo
Department of Psychology, Center for Studies in Behavioural Neurobiology, Concordia University, Quebec, Canada.
Hippocampus. 2005;15(8):1050-6. doi: 10.1002/hipo.20122.
Although several studies in rats have found that hippocampal damage has negligible effects on anterograde object-recognition memory, the findings are not entirely conclusive, because most studies have used retention intervals lasting only a few hours. We assessed the effects of neurotoxic hippocampal lesions on anterograde object recognition, using a novel-object preference test, with retention intervals that were considerably longer than in previous studies-24 h, 1 week, and 3 weeks. To promote object recognition after such long intervals, rats were familiarized with a sample object in an open field for 5 min/day for 5 consecutive days. Recognition was assessed by comparing the amount of time spent investigating the sample versus a novel object on a preference test at one of the postlearning intervals. The rats with hippocampal lesions displayed a normal novelty preference after a 3-week interval, and their performance across the three delay conditions was not significantly different from that of control rats. The findings indicate that extensive hippocampal damage spares anterograde object recognition in rats, even after retention intervals lasting days or weeks.
尽管在大鼠身上进行的多项研究发现，海马体损伤对顺行性物体识别记忆的影响微乎其微，但这些发现并不完全具有决定性，因为大多数研究使用的保持间隔仅持续几个小时。我们使用一种新物体偏好测试，评估了神经毒性海马体损伤对顺行性物体识别的影响，其保持间隔比以前的研究长得多——24小时、1周和3周。为了在如此长的间隔后促进物体识别，大鼠在开放场地中连续5天每天与一个样本物体熟悉5分钟。通过比较在学习后间隔之一的偏好测试中，研究样本物体与新物体所花费的时间量来评估识别情况。海马体损伤的大鼠在3周间隔后表现出正常的新奇偏好，并且它们在三种延迟条件下的表现与对照大鼠没有显著差异。这些发现表明，即使在持续数天或数周的保持间隔后，广泛的海马体损伤仍不会影响大鼠的顺行性物体识别。
