Women who are pregnant often report feeling a little fuzzy, a little dim and more forgetful than usual, but medical research has produced mixed data to support the so-called “baby brain” phenomenon¹.

孕妇常会觉得有些迷糊，较怀孕之前健忘不少，而针对这样的“孕傻”现象，医学研究给出了有多重数据支持的解释。

Now a study that used functional² magnetic resonance³ imaging (fMRI) confirms that mothers lose brain volume when they’re pregnant, adding to the debate.

最近，一项研究借助功能性磁共振成像，证实了孕妇的大脑会缩水，由此引发一场热议。

The authors of the new study, which was published in Nature Neuroscience, suspect the reductions they’ve detected may be a side-effect of “synaptic pruning,” which also happens to humans at age three and again during adolescence⁴.

这项全新的研究被刊登在《自然神经学》杂志上，其研究团队猜想该现象是由“神经元剪切”导致的副作用 — 一般来说，人类会在三岁时经历第一次“神经元剪切”，怀孕时经历第二次。

In pregnant women, they speculate, the gray matter shrinkage may function as a similar kind of decluttering, but one that would optimize⁵ a woman’s ability to sense what’s going on for other people, what their moods are, and when the emotional weather is shifting.

研究人员推测，孕妇的灰质萎缩现象有点类似于“清理内存”，实际上会有助于她们去感知他人的状态与情绪的变化。

This change would benefit a woman on the cusp of becoming a mother, as it would allow her to better anticipate and understand her baby’s needs.

而这种变化对于初为人母的女性来说，利大于弊 — 它能帮助女性更好地感知与理解自己孩子的需求。

The authors say that shrinking plays out different in rodents⁶. A mother’s brain changes in ways that tweak her ability to forage⁷ and hunt for food.

研究人员称，（灰质）萎缩现象对于啮齿动物而言意义非比寻常。而母亲大脑的变化则是为了增强其觅食与哺食的能力。

“Sometimes less is more. Loss of volume does not necessarily translate to loss of function.”

“有些时候，少点要比多点好。脑容量减小并不意味着功能的缺失。”

Previous studies have suggested that pregnant women are better able to understand emotions encoded in faces, especially during late-stage pregnancy⁸, while other scientists believe pregnancy turns women into better organizers.

在此之前曾有研究提出，孕妇（特别是处于妊娠晚期的孕妇）更擅长察言观色。但也有很多科学家认为，妊娠增强了女性的组织能力。

The potential upsides to “baby brain” keep adding up.

关于“孕傻”问题的潜在致使因素，可谓众说纷纭。