Mander Bryce A, Rao Vikram, Lu Brandon, Saletin Jared M, Ancoli-Israel Sonia, Jagust William J, Walker Matthew P
Sleep and Neuroimaging Laboratory.
Division of Pulmonary and Critical Care Medicine, California Pacific Medical Center, San Francisco, CA 94115, USA.
Cereb Cortex. 2014 Dec;24(12):3301-9. doi: 10.1093/cercor/bht188. Epub 2013 Jul 30.
A hallmark feature of cognitive aging is a decline in the ability to form new memories. Parallel to these cognitive impairments are marked disruptions in sleep physiology. Despite recent evidence in young adults establishing a role for sleep spindles in restoring hippocampal-dependent memory formation, the possibility that disrupted sleep physiology contributes to age-related decline in hippocampal-dependent learning remains unknown. Here, we demonstrate that reduced prefrontal sleep spindles by over 40% in older adults statistically mediates the effects of old age on next day episodic learning, such that the degree of impaired episodic learning is explained by the extent of impoverished prefrontal sleep spindles. In addition, prefrontal spindles significantly predicted the magnitude of impaired next day hippocampal activation, thereby determining the influence of spindles on post-sleep learning capacity. These data support the hypothesis that disrupted sleep physiology contributes to age-related cognitive decline in later life, the consequence of which has significant treatment intervention potential.
认知衰老的一个标志性特征是形成新记忆的能力下降。与这些认知障碍同时出现的是睡眠生理的显著紊乱。尽管最近在年轻人中发现睡眠纺锤波在恢复海马体依赖的记忆形成中发挥作用，但睡眠生理紊乱是否导致与年龄相关的海马体依赖学习能力下降仍不清楚。在此，我们证明，老年人前额叶睡眠纺锤波减少超过40%在统计学上介导了年龄对次日情景学习的影响，即情景学习受损程度可由前额叶睡眠纺锤波匮乏程度来解释。此外，前额叶纺锤波显著预测了次日海马体激活受损的程度，从而决定了纺锤波对睡眠后学习能力的影响。这些数据支持了这样一种假设，即睡眠生理紊乱导致了晚年与年龄相关的认知衰退，其后果具有重大的治疗干预潜力。
