Gilbert Paul E, Pirogovsky Eva, Brushfield Andrea M, Luu Trinh T, Tolentino Jerlyn C, Renteria Adam F
Department of Psychology, San Diego State University, San Diego, California 92120-4913, USA.
Ann N Y Acad Sci. 2009 Jul;1170:718-24. doi: 10.1111/j.1749-6632.2009.03929.x.
Memory for olfactory stimuli may be particularly affected by age-related brain changes in humans and may be an early indicator of cognitive impairment and Alzheimer's disease. Studies involving rats have offered insights into impaired cognition in aged animals, but few have examined odor memory. Therefore, it is unclear whether aged rats are a good model for possible age-related changes in odor memory in humans. Young (6-month-old) and old (24-month-old) rats were tested on associative learning tasks involving visual and olfactory stimuli. The first task examined age-related differences in discrimination and reversal learning for olfactory and visual stimuli; the second task utilized an associative contextual learning task involving olfactory and visual cues. Although old rats were able to perform the olfactory and visual discrimination tasks as well as young rats, old rats displayed significant age-related impairment on the reversal learning and contextual learning tasks. The results suggest that aging may have a similar deleterious effect on odor memory in rats and in humans. The findings may have important implications for the selection of memory paradigms for future research studies on aging. In addition, the use of an animal model to investigate the effects of aging on odor memory will allow researchers the ability to investigate how age-related neuroanatomical and neurochemical changes may result in impaired odor memory.
嗅觉刺激的记忆可能特别容易受到人类与年龄相关的大脑变化的影响，并且可能是认知障碍和阿尔茨海默病的早期指标。涉及大鼠的研究为老年动物的认知受损提供了见解，但很少有研究考察气味记忆。因此，尚不清楚老年大鼠是否是人类气味记忆中可能与年龄相关变化的良好模型。对年轻（6个月大）和年老（24个月大）的大鼠进行了涉及视觉和嗅觉刺激的联想学习任务测试。第一个任务考察了嗅觉和视觉刺激在辨别和逆向学习方面的年龄相关差异；第二个任务采用了涉及嗅觉和视觉线索的联想情境学习任务。虽然老年大鼠在嗅觉和视觉辨别任务中的表现与年轻大鼠一样好，但老年大鼠在逆向学习和情境学习任务中表现出明显的与年龄相关的损伤。结果表明，衰老可能对大鼠和人类的气味记忆产生类似的有害影响。这些发现可能对未来衰老研究中记忆范式的选择具有重要意义。此外，使用动物模型来研究衰老对气味记忆的影响将使研究人员能够研究与年龄相关的神经解剖学和神经化学变化如何导致气味记忆受损。
