Never go to bed angry, the old saying goes, or bad feeling will harden into resentment. Now scientists have found evidence to support the idea that negative emotional memories are harder to reverse after a night’s sleep.

　　有句老话说，千万不要带着怒气入睡，否则糟糕的情绪会转化成怨恨。如今科学家们发现了支持这种观点的证据：负面情绪记忆在过夜后更难逆转。

　　The study, published in the journal Nature Communications, suggests that during sleep, the brain reorganises the way negative memories are stored, making these associations harder to suppress in the future.

　　这项发表在《自然通讯》杂志上的研究称，在睡眠中，人的大脑会重新组织负面记忆的储存方式，使这些感觉日后更加难以压制。

　　“In our opinion, yes, there is certain merit in this age-old advice,” said Yunzhe Liu, who led the research at Beijing Normal University and is now based at University College London. “We would suggest to first resolve argument before going to bed; don’t sleep on your anger.”

　　“在我们看来，老话还是有它的道理的。”主导该研究的来自北京师范大学的刘云哲说。他目前的工作地点在英国伦敦大学学院。“我们建议睡觉前先解决争端;不要带着怒气睡觉。”

　　The findings could also have implications for the treatment of conditions such as post-traumatic stress disorder (PTSD), the authors said.

　　作者称，该发现还可能有助于创伤后精神紧张性精神障碍等情况的治疗。

　　The study, conducted over two days, used a psychological technique known as the “think/no-think” task to test how successfully 73 male students suppressed memories.

　　该研究在两天内完成，采用一种叫做“想不想”的心理学方法，成功测试了73名男学生是如何抑制记忆的。

　　First, the men learnt to associate pairs of neutral faces and unsettling images, such as injured people, crying children or corpses. Next, they were shown the faces again and told to either actively think of the associated picture or to consciously avoid thinking of it. When this session was conducted just 30 minutes after the initial learning, the participants were 9% less likely to remember the images that they had avoided thinking about compared to control image pairs – the suppression had been effective.

　　首先，受试者学习将中性面孔与令人不安的图片联系起来，比如受伤的人、哭泣的孩子或尸体。接着，他们会看到中性的面孔，并被告知可以主动想起相关联的图片，或者有意识地避免回忆起那些图片。当这个实验在初始学习后30分钟进行时，与对照组相比，9%的参与者不太会记起他们努力避免记起的图片-记忆抑制效果明显。

　　However, when the suppression session was carried out 24 hours after the initial learning, after a good night’s sleep, they were only 3% less likely to recall the image.

　　然而，当初始学习24小时后再进行该实验，人们在睡了一个好觉之后，只有3%的人不太会回忆起图片。

　　Brain scans offered a clue to why memories may be more difficult to unpick once they have been consolidated by sleep. Functional MRI scans of the participants revealed that newly acquired memories were represented by brain activity tightly centred on the hippocampus, the brain’s memory centre, but the overnight memories had become more distributed across the cortex.

　　脑部扫描为我们提供了为何经睡眠巩固后的记忆更难以消散的线索。对参与者的功能性核磁共振扫描表明，新获得的记忆是通过以海马(大脑的记忆中心)为中心的大脑活动呈现的。然而，过了一夜后，记忆会在大脑皮层内更加分散。

　　The authors caution that the findings were in healthy participants and are not immediately applicable to conditions like PTSD – and expecting people who have undergone a traumatic experience to start working on suppressing the memory on the same day is “probably not realistic advice”, Liu said. However the research could help design evidence-based treatments for PTSD in the future, he said.

　　作者提醒，该研究是基于健康受试者的，不能立即应用到诸如创伤后精神紧张性精神障碍等情况-而且指望有过惨痛经历的人能够当天抑制记忆“是不现实的建议”，刘说。但这项研究或许会在未来有助于对创伤后精神紧张性精神障碍设计基于经历的治疗方法，他说。

　　“We think the “re-consolidation” technique may be useful, so that we first evoke this piece of memory, and then try to suppress that,” Liu said, referring to a treatment strategy in which old information is called to mind with the aim of modifying the memory either with drugs or through behavioural interventions.

　　“我们认为重新巩固的方法或许有效，所以我们首先唤起了这部分记忆，然后试着抑制住它们。”刘说。他们参考了一种治疗方法，即通过使人们回忆起旧的信息，利用药物或行为干预来修改记忆。

（编辑：何莹莹）