记忆力下降？可能因为睡眠不足

一项最新研究发现，老年人在深度睡眠时的脑电波协调性更差，这可能影响了他们存储记忆的能力。虽然这些只是初步研究结果，但科学家们认为，这可能是解释为什么即使未患阿尔茨海默症和老年痴呆等病症的老年人也很难保存短期记忆的关键。

这篇论文的作者之一、加州大学伯克利分校的神经学与心理学教授马特·沃克告诉NPR：“就像是一名鼓手错过了一个节拍。老年人的大脑似乎无法有效同步脑电波。”

这项研究要求20名年轻成年人学习120对单词，然后研究他们在睡眠时的大脑活动，主要是慢波和快波之间的相互作用。第二天早上测试他们记住了多少对单词。在两种脑电波完美保持一致的时候，记忆效果最佳。而对60和70岁年龄段的32人进行的类似测试显示，两种脑电波的同步化失败，导致大脑无法存储记忆。

科学家们表示，为了确认研究结果，他们需要在年轻人的大脑中复制这种失败，确认它们是否会对记忆力产生类似影响。

下面是好消息： 如果这种理论最终得到证实，研究人员表示，他们认为通过透过头皮的电磁脉冲，有可能使脑电波重新同步化，改善老年人的记忆。

这将对近500亿美元的睡眠辅助行业（Research and Markets预测到2022年将达到800亿美元）带来破坏，包括睡眠跟踪仪器到200美元的高科技睡衣。

改善睡眠模式不止有益于老年人，还能给职场带来帮助。2016年的一项研究发现，美国工作者的睡眠不足每年造成约4,110亿美元的经济损失和120万个工作日损失。（财富中文网）

译者：刘进龙/汪皓

A new study finds that older people have less brain wave coordination in deep sleep—and that could be affecting their ability to store memories. While the results are still preliminary, scientists say this could be key to explaining why seniors sometimes have trouble retaining short-term memories even when they’re free of conditions like Alzheimer’s and dementia.

“It’s like a drummer that’s perhaps just one beat off the rhythm,” Matt Walker, one of the paper’s authors and a professor of neuroscience and psychology at the University of California, Berkeley tells NPR. “The aging brain just doesn’t seem to be able to synchronize its brain waves effectively.”

The study had 20 young adults learn 120 pairs of words, then studied their brains as they slept, focusing on the interaction between slow and fast waves. The next morning, they were tested to see how many pairs they remembered. When waves coincided ideally, memories were sharp. A similar test of 32 people in their 60s and 70s showed that misfires in that synchronization prevented memories from being stored.

To confirm the findings, scientists say they’ll need to reproduce the misfires in younger brains to see if it affects their memories similarly.

Here’s the good news: If the theory is proven conclusively, researchers say they believe it’s possible to resync the brain waves and improve older memories, possibly by applying electrical or magnetic pulses through the scalp.

That could disrupt the nearly $50 billion sleep aid industry (which Research and Markets says will hit $80 billion by 2022), which ranges from sleep tracking gadgets to $200, high tech PJs.

Improved sleep patterns could move beyond seniors and help the workplace too. A 2016 study found that the lack of sleep among U.S. workers is costing roughly $411 billion and losing 1.2 million work days per year.