Lupien S J, Gaudreau S, Tchiteya B M, Maheu F, Sharma S, Nair N P, Hauger R L, McEwen B S, Meaney M J
Douglas Hospital Research Center, Department of Psychiatry, McGill University, Montreal, Canada.
J Clin Endocrinol Metab. 1997 Jul;82(7):2070-5. doi: 10.1210/jcem.82.7.4075.
A group of 14 healthy elderly subjects was submitted to a nonstressful (attentional task) and a stressful (public speaking task) condition. Declarative (conscious recollection of learned information) and nondeclarative (retrieved information without conscious or explicit access) memory as well as salivary cortisol levels were measured before and after each condition. The results showed that the stressful condition significantly decreased declarative memory performance, whereas the nonstressful condition did not. Nondeclarative memory performance was not affected by either condition. Further analyses separating the subjects into responders and nonresponders in terms of stress-induced cortisol changes revealed a very different pattern of cortisol secretion and declarative memory performance in both populations. We showed that the responders presented increased cortisol levels 60 min before the actual stressor, whereas the nonresponders presented increased cortisol levels 25 min before the actual stressor. Although the responders did not differ from the nonresponders in declarative memory performance before and after the nonstressful condition, they presented a lower declarative memory performance when measured before and after the stressful condition. The early increase in cortisol levels observed in the responder group suggests that the anticipation of the stress, rather than the actual stressor per se, may have played a more significant role in the stress-induced declarative memory deficits observed in this subgroup. Together, these results show that the cortisol response to anticipation of stress and/or to stress in the elderly specifically affects those memory functions that are dependent on hippocampal activity. They also suggest that an altered cortisol responsivity to acute and/or chronic stress, with its detrimental effects on memory, could be an important factor explaining the genesis of memory deficits in aged populations.
一组14名健康的老年人被置于无压力（注意力任务）和有压力（公开演讲任务）的条件下。在每种条件前后测量陈述性（对所学信息的有意识回忆）和非陈述性（在没有意识或明确获取的情况下检索到的信息）记忆以及唾液皮质醇水平。结果表明，有压力的条件显著降低了陈述性记忆表现，而无压力的条件则没有。非陈述性记忆表现不受任何一种条件的影响。根据压力诱导的皮质醇变化将受试者分为反应者和非反应者的进一步分析显示，这两个人群中皮质醇分泌和陈述性记忆表现的模式非常不同。我们发现，反应者在实际应激源出现前60分钟皮质醇水平升高，而非反应者在实际应激源出现前25分钟皮质醇水平升高。虽然反应者在无压力条件前后的陈述性记忆表现与非反应者没有差异，但在有压力条件前后测量时，他们的陈述性记忆表现较低。在反应者组中观察到的皮质醇水平早期升高表明，对应激的预期而非实际应激源本身，可能在该亚组中观察到的应激诱导的陈述性记忆缺陷中起了更重要的作用。总之，这些结果表明，老年人对应激预期和/或应激的皮质醇反应特别影响那些依赖海马体活动的记忆功能。它们还表明，皮质醇对急性和/或慢性应激的反应性改变及其对记忆的有害影响，可能是解释老年人群记忆缺陷发生的一个重要因素。
