What causes headaches? - Dan Kwartler

翻译人员: Riley WANG 校对人员: Lipeng Chen

头痛欲裂惴惴不安中，生命暧昧不明的流淌着， 时间有其魔力，明日或今时——W.H.奥登

In ancient Greece, headaches were considered powerful afflictions.

在古希腊， 头痛被认为是严重的疾病。

Victims prayed for relief from Asclepius, the god of medicine.

头痛者会请求医药之神 阿斯克勒庇俄斯缓解疼痛。

And if pain continued,

如果疼痛依然存在，

a medical practitioner would perform the best-known remedy—

医生将会实行那项著名的疗法——

drilling a small hole in the skull to drain supposedly infected blood.

在头骨上钻一个小洞， 让感染的血液流出。

This dire technique, called trepanation,

这种可怕的方法 称为头部穿孔（环锯术）。

often replaced the headache with a more permanent condition.

在缓解头痛的同时， 这种方法带来的是更永久的病痛。

Fortunately, doctors today don’t resort to power tools to cure headaches.

运气好的话，如今的医生不会 诉诸强力工具来治疗头痛。

But we still have a lot to learn about this ancient ailment.

但对于这种古老的病痛， 我们要了解的仍有很多。

Today, we’ve classified headaches into two camps—

如今，我们将头痛分为两大类：

primary headaches

原发性头痛

and secondary headaches.

和继发性头痛。

The former are not symptomatic of an underlying disease, injury, or condition;

原发性头痛并不是 某种潜在疾病或受伤的表现；

they are the condition.

它本身就是一种疾病。

But we’ll come back to them in a minute

但我们过一会儿再聊这种疼痛，

because while primary headaches account for 50% of reported cases,

这是因为虽然原发性头痛 占到了头痛病例的50%，

we actually know much more about secondary headaches.

但我们对继发性头痛的了解更多。

These are caused by other health problems,

继发性头痛的原因 在于其他健康问题。

with triggers ranging from dehydration and caffeine withdrawal

触发疼痛的因素可能是 缺水、戒断咖啡因、

to head and neck injury,

头部或颈部受伤、

and heart disease.

以及心脏疾病。

Doctors have classified over 150 diagnosable types,

医生将其分成了150种可诊断类型，

all with different potential causes, symptoms, and treatments.

每种都有不同的潜在原因、 症状以及对应治疗方法。

But we’ll take just one common case —a sinus infection—as an example.

我们拿最普遍的鼻窦炎作为例子。

The sinuses are a system of cavities

鼻窦是一个腔系统，

that spread behind our foreheads, noses, and upper cheeks.

分布在我们的前额、 鼻子以及面颊上半部。

When our sinuses are infected,

当鼻窦被感染时，

our immune response heats up the area,

免疫系统会使该区域升温，

roasting the bacteria and inflaming the cavities well past their usual size.

从而杀灭细菌， 这使得腔体比平时红肿许多。

The engorged sinuses put pressure on the cranial arteries and veins,

充血肿胀的鼻窦 会给颅内动脉和血管增压，

as well as muscles in the neck and head.

脖子和头部的肌肉 也同样感受到更大压力，

Their pain receptors, called nociceptors, trigger in response,

肌肉的痛觉感受器由此触发，

cueing the brain to release a flood of neuropeptides

向大脑传递大量神经肽。

that inflame the cranial blood vessels, swelling and heating up the head.

它们会使颅内血管充血， 使大脑肿胀发热。

This discomfort, paired with hyper-sensitive head muscles,

这种不适感会协同 高度敏感的头部肌肉

creates the sore, throbbing pain of a headache.

共同产生酸痛和阵阵抽痛。

Not all headache pain comes from swelling.

并非所有的头痛都来自于肿胀，

Tense muscles and inflamed, sensitive nerves

紧张的肌肉、发炎且敏感的神经

cause varying degrees of discomfort in each headache.

都会引起不同程度的不适感。

But all cases are reactions to some cranial irritant.

但所有头痛都是 对某些颅内刺激物做出的反应。

While the cause is clear in secondary headaches,

虽然继发性头痛的病因现已明了，

the origins of primary headaches remain unknown.

但原发性头痛的起因 却仍不得而知。

Scientists are still investigating potential triggers

科学家仍在研究 哪些触发因素

for the three types of primary headaches:

会引起以下三种原发性头痛：

recurring, long-lasting migraines;

反复出现、持久的偏头痛，

intensely painful, rapid-fire cluster headaches;

痛感强烈接连不断的丛集性头痛，

and, most common of all, the tension headache.

以及最普遍的紧张性头痛。

As the name suggests,

从名字可以看出，

tension headaches are known for creating the sensation

紧张性头痛可以制造出

of a tight band squeezed around the head.

头部被一条带子紧紧勒住的痛感。

These headaches increase the tenderness of the pericranial muscles,

这些头痛加剧了 颅骨骨膜肌肉的敏感性，

which then painfully pulse with blood and oxygen.

它随血液和氧气疼跳动， 产生疼痛。

Patients report stress, dehydration, and hormone changes as triggers,

据病人反映，他们都经历了 压力、缺水、荷尔蒙变化，

but these don’t fit the symptoms quite right.

但是这些与症状并不完全相符。

For example, in dehydration headaches,

举例来说，

缺水产生头痛时 大脑额叶通常会缩小，

the frontal lobe actually shrinks away from the skull,

creating forehead swelling

导致前额肿大。

that doesn’t match the location of the pain in tension headaches.

但这与紧张性头痛的 疼痛位置并不相符。

Scientists have theories for what the actual cause is,

科学家推断头痛的真正原因

ranging from spasming blood vessels

包括血管痉挛，

to overly sensitive nociceptors,

以及过度敏感的疼痛感受器，

but no one knows for sure.

但没人对此有十足的把握。

Meanwhile, most headache research is focused on more severe primary headaches.

与此同时，大多数头痛的研究 都集中在更严重的原发性头痛上。

Migraines are recurring headaches, which create a vise-like sensation on the skull

偏头痛会反复发作， 使头骨产生被钳子夹痛的感觉。

that can last from four hours to three days.

这种疼痛可以持续4小时到3天。

In 20% of cases, these attacks are intense enough

在20%的偏头痛病例中，

这种疼痛产生的电能量 能够超过大脑的负荷，

to overload the brain with electrical energy,

which hyper-excites sensory nerve endings.

使得感受神经末梢高度兴奋。

This produces hallucinations called auras,

这会使人产生称作光晕的幻觉，

which can include seeing flashing lights

包括看到闪亮的灯光、

and geometric patterns and experiencing tingling sensations.

几何图形和感受到刺痛。

Cluster headaches, another primary headache type,

丛集性头痛是另一种主要的头痛，

cause burning, stabbing bursts of pain behind one eye,

能够在一只眼睛后产生烧灼刺痛，

leading to a red eye, constricted pupil, and drooping eyelid.

会导致眼红、 瞳孔收缩、眼皮发沉。

What can be done about these conditions,

这些病症严重影响了 人们的生活质量，

which dramatically affect many people’s quality of life?

那么该如何解决它们呢？

Tension headaches and most secondary cases

对于紧张性头痛 和大多数继发性头痛而言，

can be treated with over-the-counter pain medications,

非处方止痛药可以缓解症状，

such as anti-inflammatory drugs that reduce cranial swelling.

例如消炎药可以减少颅内肿胀。

And many secondary headache triggers,

许多导致继发性头痛的触发因素，

like dehydration,

例如失水、

eye strain,

眼睛疲劳、

and stress,

压力等，

can be proactively avoided.

可以采取主动预防的方式避免。

Migraines and cluster headaches are more complicated,

偏头痛和丛集性头痛则更加复杂。

and we haven’t yet discovered reliable treatments that work for everyone.

我们目前还未发现对所有人 都行之有效的可靠疗法。

But thankfully, pharmacologists and neurologists are hard at work

但庆幸的是， 药剂师和神经学家正在

努力攻克这些 对大脑至关重要的难题。

cracking these pressing mysteries that weigh so heavily on our minds.