(单词翻译:单击)
Imagine sitting down to dinner, eating everything on the plate, and feeling half as full as usual.
想象一下，坐下来吃晚饭，把盘子里的东西都吃了，感觉像平常一样是半饱。
Or maybe going to shave, but weirdly enough, it takes half the time.
或者是去刮胡子，但奇怪的是，花了一半的时间。
Losing half of the world sounds like a weird, abstract dream state.
失去一半的世界听起来像是一种怪异、抽象的梦境。
But for those that develop hemispatial neglect, that's exactly what happens, without them even realizing it.
但对于那些发展为偏侧空间忽视的人来说，这就是所发生的事情，但他们甚至都没意识到。
This condition isn't totally understood,
这种情况还没被完全理解，
but research into it has given us some fascinating insights into just how we pay attention.
但对它的研究给我们提供了一些注意力工作方式的有趣见解。
Hemispatial neglect is a condition that causes people to completely neglect one of their sides.
偏侧空间忽视，是一种使人们完全忽视自己一侧的情况。
As in, they're completely unable to pay attention to half their world.
好像他们完全不能关注到另一半世界。
Usually it's the result of a stroke, and,
这通常是中风的结果，
while estimates vary as to exactly how often it happens, it's relatively common as far as neurological conditions go.
虽然对其确切发生频率的估计各不相同，但就神经系统状况而言，这相对来说很常见。
People who live with this condition are typically unable to do anything that requires attention to their neglected side.
有这种疾病的人，生活中通常无法做任何需要关注被忽视一侧的事。
They might only do their makeup on one side of their face or only read one side of a newspaper.
他们可能只在脸的一侧化妆，或者只看报纸的一面。
And if people approach them from their neglected side, they might not notice.
如果人们从他们被忽视的一侧接近他们时，他们可能不会注意到。
Hemispatial neglect doesn't just apply to day-to-day life, either — it can also show up in your memories.
偏侧空间忽视仅适用于日常生活，它也会表现在记忆方面。
For instance, researchers in Italy asked 96 patients with hemispatial neglect to picture themselves standing in a familiar public square
例如，意大利研究者让96名偏侧空间忽视患者想象自己站在一个熟悉的广场上，
— and asked them to describe what they would see.
并要求他们描述将看到什么。
The participants successfully described the right side of the square, and totally neglected to mention any of the features of the left side
参与者成功地描述出广场的右侧，而完全未提及左侧的任何特征，
— even though they were just picturing being there.
即使他们只是想象自己在那里。
Then, the researchers asked them to imagine standing on the opposite side of the square and to describe their surroundings again.
然后，研究者让他们想象站在广场的另一边，并再次描述周围的环境。
Now the participants were only able to describe the things on their new right side,
现在，参与者只能描述新的右侧的东西，
even though just moments ago they hadn't registered those things at all.
尽管他们刚才还未注意到这些东西。
As for everything they'd noticed in the first round —
至于他们在第一轮中注意到的所有东西——
the features that were now on their left — they neglected those entirely.
现在在他们左侧的那些特征——他们完全给忽略了。
As dramatic as that sounds, someone living with hemispatial neglect wouldn't easily realize one side had disappeared.
听起来很戏剧化，偏侧空间忽视患者不会轻易意识到其中一侧已经消失。
But from the outside, the signs are very clear, and doctors can easily test for the condition.
但从外部看，症状非常明显，医生可以很容易地检测到病情。
One common clinical test is to ask a patient to draw the face of an analogue clock.
一个常见的临床测试是让病人画出一个模拟时钟的表面。
If they're neglecting one of their sides, all the numbers end up smushed together on one side or the other.
如果他们忽略了自己的一侧，所有的数字最终都会出现在这一侧或另一侧。
But even though it seems like the brains of people with this condition just block out a part of the world completely,
但是，尽管患有这种疾病的人，其大脑似乎只是完全屏蔽了世界的一部分，
research has shown that, on some level, they are still processing information from their neglected side.
但研究表明，在某种程度上，他们仍在处理被忽略一侧的信息。
Like, experiments have shown that people can process the meaning of a word that's only shown to their neglected side,
比如，实验表明，人们能处理一个只显示在被忽略一侧的单词含义，
even if they have no awareness of actually seeing the word.
即使他们没有意识到实际看到了这个单词。
Meaning, just the fact that they're shown the word will affect their behavior on decision-making tasks, even if they don't know they saw it.
也就是说，只要给他们呈现这个词，就会影响他们在决策任务上的行为，即使他们不知道自己看到了。
So, the problem isn't that the information isn't getting in; the brain is just not paying attention to it.
所以，问题不在于信息没有进入大脑，只是大脑没有注意到。
So what makes the brain just… forget a whole side of the world exists?
那么，是什么让大脑忘记了另一侧的存在？
One clue comes from the fact that hemispatial neglect often happens after strokes and other types of brain damage
一个线索来自这样一个事实，即中风和其他类型的脑损伤影响到顶叶的一部分，
that affect a part of the parietal lobe called the inferior parietallobule.
即顶叶下顶叶后，通常会发生偏侧空间忽视。
This part of the brain is involved with paying attention to where things are.
大脑这一部分与注意事物的位置有关。
So when it gets damaged, you might be unable to notice things in certain locations.
所以当它受损时，可能无法注意到某些地方的东西。
But there's an unusual twist.
但是有一个不寻常的转折。
Although hemispatial neglect can happen on either side of the brain,
尽管大脑的任何一侧都可能发生偏侧空间忽视，
it's usually the left side of the world that disappears.
但通常是左侧的内容消失。
And since the right side of the brain controls the left side of the body, it comes from damage to the right parietal lobe.
由于大脑的右侧控制着身体的左侧，它来自于右侧顶叶的损伤。
It can happen on the other side,
也可能发生在另一侧，
but in general, people with an injury on the left hemispherere cover from hemispatial neglect quickly and without intervention.
但一般来说，左半球受伤的人很快就会在没有干预的情况下，从偏侧空间忽视的情况下恢复过来。
On the surface, that seems bizarre.
从表面上看，这似乎很奇怪。
But this mismatch can actually tell us a lot about how our brains manage our attention.
但这种不匹配，实际上能告诉我们很多关于大脑如何管理注意力的情况。
Scientists have two main hypotheses about why this might happen.
科学家们对于为什么发生这种情况有两个主要的假设。
Although both parietal lobes are involved in spatial awareness —
尽管两侧顶叶都与空间意识有关，
or, telling us where things are in space — the left parietal lobe is also highly specialized for processing language.
或是告诉我们空间中的东西在哪里，但左顶叶也非常擅长处理语言。
So, scientists think that it may only have the bandwidth to attend to space on one side the right.
因此，科学家们认为它可能只有足够的带宽来处理右边一侧的空间。
Meanwhile, the right parietal lobe deals with spatial awareness on both sides.
同时，右顶叶处理两侧的空间意识。
So it can pick up the slack if you damage your left parietal lobe.
因此，如果左顶叶受损，它可以缓慢地恢复。
But it doesn't work the other way around If you damage your right parietal lobe,
但是，如果损伤了右顶叶，
there's no backup — you just lose awareness of your left side.
而没有支援的话，你只会失去对左侧的意识。
At least, that's the idea.
至少是这种理念。
But some clinical observations of patients with hemispatial neglect suggest there's more to the story.
但是，对偏侧空间忽视患者的一些临床观察表明，这个故事中要讲述的内容还有更多。
Specifically, there appears to be a link between attention and alertness.
具体来说，注意力和警觉之间似乎存在关联。
People with hemispatial neglect have trouble staying alert, and this condition isn't the only time scientists have seen a connection between attention and alertness.
偏侧空间忽视患者很难保持警觉，而这种病症并不是科学家们唯一一次发现的注意力和警觉之间的联系。
As healthy people start to fall asleep, research has shown that they also begin to neglect their left side.
研究表明，当健康人入睡时，他们也开始忽视左侧。
For example, in one study, participants who were asked to identify the direction of a sound
例如，在一项研究中，研究人员要求参与者在入睡时辨别声音的方向，
as they drifted to sleep typically identified sounds on the left as coming from the right.
参与者通常认为左边的声音来自右侧。
Scientists are suggesting here that as we drift off to sleep,
科学家们建议，当我们渐渐入睡时，
the left side begins to suppress activity in the right hemisphere that helps keeps us awake — that way we can switch off for the night.
左侧大脑开始抑制右半球的活动，这样有助于我们保持清醒，这样我们就可以在晚上休息。
According to this hypothesis, as that activity gets suppressed, the same brain regions involved in hemispatial neglect become less active too,
根据这种假设，这种活动被抑制时，大脑中参与偏侧空间忽视的相同区域也变得不那么活跃，
and we lose awareness of our left side.
我们就失去对左侧的意识。
Scientists still don't have a perfect theory nailed down.
科学家们对此仍然没有完美的理论。
But cases of hemispatial neglect make it possible to isolate aspects of the way typical brains function.
但是，偏侧空间忽视的病例使得分离典型大脑功能的各个方面成为可能。
Most of us go about our lives seeing the world as one big cohesive experience,
我们中的大多数人在生活中体会到的世界是一个巨大的、有凝聚力的经历，
and can't recognize the different aspects of that experience.
却无法认识到这种经历的不同方面。
But this condition goes to show that your brain is constantly working to maintain one really impressive balancing act.
但这种病症表明，大脑一直在努力维持一种惊人的平衡行为。
And that when it comes to nailing down all the tricks behind that act,
而且，要确定这一行为背后的所有伎俩时，
we still have a lot to learn from conditions like hemispatial neglect.
我们仍然需要从诸如偏侧空间忽视之类的病例中学到很多东西。
Thanks for watching this episode of SciShow Psych!
感谢收看本期《心理科学秀》！
And a special thanks to this month's President of Space, Matthew Brant, for helping us bring you this episode!
特别感谢本月的太空总裁马修·布兰特，他帮助我们制作了本集节目！
Matthew is one of our patrons on Patreon, the wonderful community of supporters helping us make science education on the internet free for everybody.
马修是我们Patreon的赞助人之一，Patreon是一个很棒的支持者社区，帮助我们在互联网上为大家免费提供科学教育。
If you are not a patron but are interested in supporting what we do, you can find out more at patreon.com/SciShow.
如果你还不是赞助人，但有兴趣支持我们的工作，请访问patreon.com/SciShow查询更多信息。
