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As I was sitting in the office one day, a colleague at a desk 3ft away looked up with a curious expression.
She glanced around searchingly until her gaze settled on me.
‘My dear,’ she said in her customary grand manner, ‘are you wearing perfume?’
I nodded, replying: ‘Do you like it?’ She smiled at me graciously.
‘It’s simply frightful,’ she announced at a volume akin to the average loudhailer, adding: ‘So cheap!’
Choosing perfume by guesswork is just one of the pitfalls of my life as an anosmic — a person with no sense of smell.
From the fragrance of roses to the smell of burning, I’m oblivious to them all.
I am among the one in 5,000 people born anosmic — others lose their sense of smell through head trauma (Tottenham manager Harry Redknapp lost his after a car crash) or as the result of a simple flu or cold virus.
It’s thought that 200,000 Britons have anosmia — famous sufferers have included William Wordsworth, INXS singer Michael Hutchence and actor Bill Pullman.
Yet the vast majority of people able to smell have not only never heard of anosmia, but its existence has not occurred to them. The unfailing response I receive is a blank stare, before they insist: ‘But you must be able to smell baking bread or sour milk.’
If I were blind, no one would say: ‘But you must be able to see this very large mountain or that very bright light.’ So, to repeat . . . I. Can’t. Smell. At all.
‘The estimated number of anosmics is likely to be hugely inaccurate because most just cope and never mention it,’ says smell specialist Professor Tim Jacob, of Cardiff University’s School of Biosciences.
‘Lots of congenital anosmics say they don’t even realise they have no sense of smell until their teens.
'As young children they can’t understand the concept of smell but do not wish to appear different to their peers, so they learn the appropriate reactions to good or bad smells from other people’s cues.’
He adds: ‘To most people anosmia is unimportant. The condition hasn’t even entered the consciousness of the medical profession. It has no NHS budget and GPs have no idea about it.’
Even ear, nose and throat specialists aren’t trained in anosmia, according to Professor Jacob, despite the fact that dozens of viruses of the upper respiratory tract can cause it.
He says: ‘I get letters constantly from people who feel very let down by the medical profession and who are desperate for answers.’
Famous sufferers of anosmia include actor Bill Pullman (left) and the late INXS singer Michael Hutchence (right)
The fact is those answers are few. Put simply, our ability to smell is generated by receptor nerve cells at the top of the nose — these send signals via the olfactory nerves to the olfactory cortex in the brain.
In anosmia, the olfactory nerves are damaged or die (people born with anosmia may lack these nerves completely — this form of the condition is genetic, although it can skip generations).
‘In anosmia caused by head trauma or virus, the olfactory nerve is damaged,’ explains Professor Jacob.
‘Most human nerves do not regenerate. If they get broken or cut, that’s that, although research is progressing.’
In other words, anosmics are largely stuck with it. Those with acquired anosmia may experience the temporary return of smell for reasons not yet understood. They may also experience phantosmia — the detection of an odour where none is present.
‘It works the same way as phantom pains in a lost limb,’ explains Professor Jacob.
‘If you no longer receive sensory input from the nose, then the brain regions dealing with smell receive random information.Then what’s left of the nerve pathway can trigger the region of the brain dealing with smell, triggering an apparent smell even though there is none.’
This is the case with investment banker Ben Colegrave, 30, who became anosmic after a life-threatening head injury in a road accident seven years ago.
‘The other day my girlfriend and I got into a taxi which to me smelled strongly of curry,’ he recalls.
‘But my girlfriend said there was no smell of curry. That happens every now and again.
‘I miss the memory triggers of smells, and being able to associate a smell with an individual person. Above all I miss the excitement of breathing in an unfamiliar aroma as you get off the plane in a new country.’
Ben is sanguine about his anosmia (‘I could have died, so it doesn’t seem very important’), but loss of smell can be devastating.
According to Professor Jacob, 17 per cent of people who become anosmic subsequently suffer clinical depression, often because their sensory experience of food is so depleted.
Anosmics retain a normal sense of taste, distinguishing between sweet, sour, salt, bitter and umami (savoury) like everyone else.
However, we can’t distinguish between flavours, as this is almost entirely down to smell. Molly Birnbaum was 20 and a would-be chef when a head injury in a road accident left her anosmic.
‘Food had been my consuming passion,’ says Birnbaum, now a writer, in her just published book Season To Taste.
‘Then I dreaded eating. The scent of garlic and roasting meat fell on lifeless olfactory nerves. A bite of steak may as well have been a chunk of warm cardboard.
‘I examined every piece of food. That milk: fresh or sour? That spinach: new or old? I had only the visual to guide me.’
Professor Jacob says anosmics use other signals, such as texture, acidity and hydration, to compensate for absence of flavour. Ben Cohen, of ice cream duo Ben & Jerry’s, is a congenital anosmic and insisted on large chunks in their products to improve his perception of flavour.
‘Of course, smell also acts as a hazard warning,’ says Professor Jacob, ‘not only against lethal dangers such as gas or fire, but against food which is going off.’ As someone who’s accidentally eaten rotten fish, I can confirm it is unbelievably disgusting.
Researchers are garnering scattered facts about anosmia. Diminished ability to smell can be an early sign of Parkinson’s.
‘Some of the main brain degeneration seen in Parkinson’s is seen first in the olfactory bulb (where the olfactory nerves meet),’ says Professor Jacob.
‘That said, many men lose around half their sense of smell by the age of 80 simply as a function of age. Women tend to retain it.’
Anosmia is also linked to loss of libido, though again, it’s not clear why.
As for us congenitals, we rarely think about our anosmia, as it has always been our normality.
But I do quite often wonder if either I or my house smell terrible, and people are simply too polite to tell me. And I’ve learned it pays to take a friend along when buying perfume.
参考译文：
有一天我正在办公室里坐着，一个离我有三英尺远的同事突然一副好奇的表情，好像正在附近寻找着什么，而最后她把目光锁定在了我身上。
“我的天哪，”她用她惯用的严肃的语气问我，“你喷香水了？”
我点了点头，说道：“你喜欢这个味道么？”而她则是回应了我一个温柔的微笑。
“真可怕，这香水闻起来…”，她用和大喇叭差不多的音量接着说道，“好廉价！”
作为一个嗅觉缺失者——对气味没有感知能力的人，只凭借想象来选择香水只是嗅觉丧失症给我的生活带来的诸多不便之一。
从玫瑰花的香味到燃烧的气味，我通通感知不到。
大约每五千个人中会有一个人患有先天性的嗅觉缺失症，我就是其中一员——还有一些人因为头部创伤（热刺队的经理哈里•雷德克纳普在一场车祸之后丧失嗅觉）或被流感或伤寒病毒感染，后天失去了嗅觉。
据说有嗅觉丧失正的英国人有200，000个之多——其中比较有名的有威廉姆•华滋华斯，伊克斯乐队的主唱迈克尔•哈琛斯和演员比尔•普尔曼。
然而，拥有正常嗅觉的大多数人不仅仅是从未听说过嗅觉缺失症，而是对它的存在完全没有任何概念。人们在听说之后给我的答复永远是面无表情的凝视，之后他们还会坚持说：“但是你肯定还是能闻见烤面包味或酸牛奶味是吧。”
但如果我是盲人，肯定不会有人对我说：“但是你肯定还是能看见那座大山或者很亮的光是吧。”因此，我总在重复一句话……我，啥，都，闻，不，见。
“患有嗅觉缺失症的估计人数很可能存在严重误差，因为很多人都隐瞒了这件事，”卡迪夫大学生物学院的嗅觉专家，蒂姆•雅各布教授说。
“许多先天性嗅觉丧失正患者说，他们在十岁以前甚至都没意识到自己没有嗅觉。”
“小孩虽然没有完全理解嗅觉的概念，但因为他们不想和别的孩子表现的不同，所以他们就通过模仿别人，同他人一样也对好的或不好的气味做出适当的反应。”
他还说：“对大多数人来说，嗅觉缺失症根本不重要。而这种情况也还没有进入医疗从业者的自觉当中。这类患者不享受英国国民健康保险制度（NHS）中规定的补偿，普通开业医生对此也毫无概念。”
据雅各布教授说，许多耳鼻喉科专家也并未对嗅觉丧失症有过专门训练，尽管有好几十种上呼吸道病毒都有可能引发这种病。
他说：“我不断接到患者的信件，他们或是因为医疗人员而对此感到失望，或是极其渴望得到关于这病的解决办法。”
比较有名的嗅觉丧失症患者有演员比尔•普尔曼，和伊克斯乐队的主唱迈克尔•哈琛斯。
但事实是，这病确实没有治疗办法。简单的说，我们能够闻到气味是因为鼻腔粘膜上的神经细胞能接受气味的信号——然后这种信号通过嗅觉神经传导到大脑中的嗅皮质。
患有嗅觉缺失症的人，其嗅觉神经是损坏的或死亡的（天生嗅觉缺失的人可能是生来就完全没有嗅觉神经——这种情况就是可遗传的，尽管发生隔代遗传也会随基因传递下去）。
“而因为头部损伤或病毒引起的嗅觉缺失症，患者的嗅觉神经是被损坏了。”雅各布教授解释道。
“一般人类的大多数神经都不会再生了。如果他们被损坏或切断了，那就无法改变了，尽管这方面的研究也在进行。”
换句话说，嗅觉缺失症在很大程度上说是无法摆脱的。那些后天嗅觉确实的人们有可能会因为某些原因获得暂时性的嗅觉恢复。他们还可能会出现幻嗅——感知到根本不存在的气味。
“这个原理和患肢痛感差不多，”雅各布教授解释道。
“如果你再也接收不到来自于鼻子的嗅觉信号，大脑的嗅觉区域就会接收到一些随机信息。然后其他的神经传导途径就会触发大脑的嗅觉区域，产生一些不存在的嗅觉感受。”
这就是30岁的投资银行家Ben Colegrave的案例，他在七年前的一场危及生命的交通事故中损伤了头部，之后便患上了嗅觉缺失症。
“前几天我和我女朋友上了一辆出租车，我闻到了一股很强烈的咖喱味，”他回忆道。
“但是我的女朋友说根本没闻到咖喱味。这种情况时常发生。”
“我怀念还有嗅觉的那段时光，那时候我可以吧闻到的气味与一个人联想起来。总之，我现在已无法体验那种呼吸到一种不熟悉的气味的新鲜感，就像刚从飞机上下来踏上一片从未到过的土地时的感觉一样。”
Ben能很乐观的看待他的嗅觉缺失症（“在那次事故中我差点没命，而这点小病就显得不那么重要了”），但是从此以后闻不到味道对他来讲也是个重大的打击。
雅各布教授表示，有17%的人在嗅觉缺失症之后患上了忧郁症，经常是因为他们对于食物的感觉变得越发贫乏了。嗅觉缺失症的患者还能保持与正常人一样的味觉，能够分辨甜味，酸味，咸味，苦味和鲜味。
然而，他们并不能区分不同味道，因为那主要取决于气味。莫丽•伯恩鲍姆在20岁即将成为厨师的时候经历了一场车祸，头部损伤导致她丧失了味觉。
“食物曾经是我消费的动力，”成为了作家的伯恩鲍姆在她刚出版的书《品味四季》中如是写道。
“但是之后，我对饮食产生了恐惧。大蒜和烤肉散发出来的气味落到了我死亡的味觉神经上。咬上一口牛排的感觉就好像是咬上了一块温热的厚纸板。”
“我会去反复检查每一块食物。这些牛奶是新鲜的还是坏掉的？那些菠菜是新的还是老的？现在我只能靠视觉来引导我了。”
雅各布教授说，丧失嗅觉的患者们还会用其他特征来弥补其嗅觉的不足，比如质地，酸度和水分含量等。班杰瑞冰激凌品牌的创始人之一本•科恩就是一个先天嗅觉缺失者，他坚持把产品做成量大型，来提升人们对冰激凌口味的感知。
“当然，嗅觉也会负担起危险警示的作用，”雅各布教授说，“它不仅会在感受到对汽油或燃烧的有毒气味发出警告，还会在感知到食物变质后发出警告。”因为如果有人不小心吃了腐烂的鱼，我能肯定那味道会非常非常恶心。
研究者不断的获得了一些关于嗅觉缺失症各个方面的信息。比如，嗅觉能力的减弱可能是帕金森氏症的早期预兆。
“一些在帕金森氏症中显示出的大脑退化最先发生在嗅球（嗅觉神经聚集的地方），”雅各布教授说。
“还有一说，许多男性在80岁的时候仅仅因为衰老而丧失了将近一半的嗅觉能力，而女性则不然。”
嗅觉缺失症貌似还与性欲的降低有关，尽管原因还不是很明确。
但是对我们这些先天性嗅觉缺失的人来说，我们倒很少想关于这病的事儿，因为这已经成为一种常态了。
但是我经常会想，如果我或者我的家里闻起来特别糟糕，而人们还又没好意思告诉我的话会是怎样呢。虽然我现在已经会在买香水的时候拽上一个朋友帮我挑了。
相关阅读：人类嗅觉识别机制探密
