“DO NOT FEAR KORO,” screamed the headline in the Straits Times newspaper on November 7, 1967. In the preceding days, a peculiar phenomenon had swept across Singapore. Thousands of men had spontaneously become convinced that their penises were shrinking away – and that the loss would eventually kill them.
Mass hysteria had quickly taken hold. Men desperately tried to hold onto their genitals, using whatever they had to hand – rubber bands, clothes pegs, string. Unscrupulous local doctors cashed in, recommending various injections and traditional remedies.
The word on the street was that the sudden penis withering was caused by something the men had eaten. Specifically, the locals were suspicious of meat from pigs that had been vaccinated in a programme the government had imposed on Singaporean farms. Pork sales quickly plummeted.
Though public health officials scrambled to contain the hysteria outbreak, explaining that it was caused by “psychological fear” alone, it didn’t work. In the end, over 500 people sought treatment at public hospitals.
As it happens, the fear of losing one’s penis is more mainstream than you might think. It pops up fairly regularly in certain cultures across the globe. In South-east Asia and China, it’s common enough that it even has a name: “koro”, possibly – and rather graphically – after the Javanese word for tortoise, referring to how it looks when they retract their heads into their shells.
Koro has a history stretching back thousands of years, but the most recent outbreak occurred in 2015, in eastern India. It affected 57 people, including eight women, for whom it tends to manifest as a fear that their nipples are retreating into the body.
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Koro is considered a culture-bound syndrome – a mental illness that only exists in certain societies. For decades, “untranslatable” disorders like these were studied as mere scientific curiosities, which existed in parts of the world where people apparently didn’t know any better.
Western mental illnesses, on the other hand, were viewed as universal – and you could guarantee that every “bona fide” problem would be found in the hallowed pages of the American psychiatric bible, the Diagnostic and Statistical Manual of Mental Disorders (more commonly known as the DSM). But today scientists are increasingly realising that this is not the case.
In the Islamic world, mental illnesses are often attributed to evil spirits, or “jinns” (Credit: Alamy)
In the central plateau region of Haiti, people regularly fall sick with “reflechi twòp”, or “thinking too much”, which involves ruminating on your troubles until you can barely leave the house. In South Korea, meanwhile, there’s “Hwa-byung” – loosely translated as “rage virus” – which is caused by bottling up your feelings about things you see as unfair, until you succumb to some alarming physical symptoms, like a burning sensation in the body. Dealing with exasperating family members is a major risk factor – it’s common during divorces and conflicts with in-laws.
Though to the uninitiated, these mental illnesses might sound eccentric or even made-up, in fact they are serious and legitimate mental health concerns, affecting vast numbers of people.
It’s estimated that Hwa-byung affects around 10,000 people in South Korea every year – mostly older married women – and research has shown that it has a measurable footprint in the brain. In 2009, brain scans revealed that sufferers had lower activity in an area known to be involved in tasks such as emotion and impulse control. This makes sense, given that Hwa-byung is an anger disorder.
The consequences of culture-bound syndromes can be devastating. Koro attacks can be so convincing that men cause serious damage to their genitals, as they try to stop them receding. Those who suffer from reflechi twòp are eight times more likely to have suicidal thoughts, while Hwa-byung has been linked to emotional distress, social isolation, demoralisation and depression, physical pain, low self-esteem, and unhappiness.
Intriguingly, some untranslatable illnesses have recently been disappearing, while others are spreading to new parts of the globe. Where do these sicknesses come from, and what determines where they’re found? The quest for answers has been gripping anthropologists and psychiatrists for decades – and now their findings are shaping our understanding of the very origins of mental illness itself.
The award for the culture-bound illness with the most surprising history surely has to go to “neurasthenia” (also known as “shenjing shuairuo”). Though it mostly occurs in China and South-east Asia today, it’s actually a colonial malady from the 19th Century.
Neurasthenia was popularised by the American neurologist George Miller Beard, who described it as an “exhaustion of the nervous system”. At the time, the Industrial Revolution was leading a massive upheaval of everyday life, and he believed that neurasthenia – a syndrome of headaches, fatigue and anxiety, among other things – was the result.
Sometimes culture-bound illnesses only occur in a certain social class or era of time (Credit: Science Museum/ Wellcome Collection)
“Once famous novelists like Marcel Proust were diagnosed, it became this super popular condition,” says Kevin Aho, a philosopher from Florida Gulf Coast University, who has studied the history of the illness. “It was almost fashionable and indicated sensitivity, intellectual creativity – it was kind of an indicator of one's own cultivated refinement.”
Eventually neurasthenia spread to European colonies around the world, where it was enthusiastically picked up by moustachioed officers and their wives, as a way to add a label to their general feelings of homesickness. According to a survey taken in 1913, neurasthenia was the most prevalent diagnosis among white colonisers in India, Sri Lanka (then Ceylon), China and Japan.
As the years passed, neurasthenia gradually lost its appeal in the West, as it became associated with more serious psychiatric problems. Now it’s been forgotten about altogether. But elsewhere, the opposite happened: it was adopted as a diagnosis that didn’t come with stigma of mental illness and remains in use to this day.
In some parts of Asia, people are more likely to say they have neurasthenia than depression. A 2018 study of a random sample of adults from Guangzhou, China, found that 15.4% identified as having the former versus 5.3% who said they had the latter.
The final twist is that now neurasthenia is vanishing from Asia too. “When I first interviewed patients at a psychiatric hospital in Ho Chi Minh, Vietnam, in 2008, almost all of them said that they had neurasthenia,” says Allen Tran, a psychological anthropologist from Bucknell University, Pennsylvania. “Then when I did some follow-up research 10 years later, I think only one person in my sample said they had it.”
So what’s going on?
There are two possible scenarios playing out here. First, there’s the idea that the entirety of humankind is susceptible to the same limited range of mental sicknesses – we all feel anxious and depressed, for example, but the way we talk about these things varies depending on when and were you live.
The fact that culture-bound illnesses can be gained and lost within a single community, and with such rapidity, is an important clue. This suggests that they’re not driven by, say, genetic factors, as this kind of change usually takes hundreds or thousands, rather than tens of years. Instead, the swift extinction of neurasthenia in Vietnam could be down to the growing popularity of the concept of anxiety, which has been imported from overseas. It’s possible that the actual incidence of mental illness has been the same all this time – but conceptually, one has been replaced with the other, says Tran.
In some cultures, distress and grief can manifest with physical symptoms (Credit: Alamy)
Along these lines, the author and medical historian Edward Shorter has suggested that each society has its own “symptom repertoire”, which is the array of symptoms from which we unconsciously draw when we start to feel mentally unwell.
For example, a grieving Victorian woman might say she felt faint, where her modern counterpart in the UK might suggest she felt anxious or depressed, and someone in the same position in China might explain they had a stomach-ache. In this scenario, they would all have had identical experiences – perhaps they all felt faint, on edge, or suffered physical pains – but the symptoms they paid the most attention to were different, depending on what was considered normal in their society.
In Britain, the out-dated illness “hysteria” – which was thought to mostly affect women, and caused fainting, emotional outbursts and nervousness – disappeared from the public consciousness in the early 20th Century. But Shorter suggests that it didn’t actually die out. Instead, the array of symptoms we look out for evolved. Today the same mental phenomenon hides behind other diagnoses, such as depression.
I would say that there are definitely instances where the meaning that is attributed to experiences actually changes biologically what that experience is – Bonnie Kaiser
This fits with another concept that has been gaining in popularity, “idioms of distress”, which suggests that each culture has certain acceptable, established ways of expressing emotional anguish at any given time. In one society, you might drink excessively, while in others you might say you’re a victim of witchcraft, or diagnose yourself with illnesses like koro or depression.
For example, in the Islamic world, it’s widely believed that it’s possible to become possessed by “jinns”, or evil spirits. They can be good, bad, or neutral, but they’re generally blamed for erratic behaviour. The concept is so mainstream, it’s even in the Muslim holy book, the Koran. “A lot of my patients do hold these beliefs quite strongly,” says Shahzada Nawaz, a consultant psychiatrist at North Manchester General Hospital in the UK.
Nawaz explains that the ability to invoke jinns is particularly useful in Islamic cultures, because of the stigma that tends to accompany Western mental illnesses. One study of 30 Bangladeshi patients attending a mental health service in an east London borough found that, though they had been diagnosed with a variety of problems between them, such as schizophrenia and bipolar disorder, their family members often felt that jinn possession was responsible.
"Neurasthenia" is a colonial malady from the 19th century, which mostly occurs in China and Southeast Asia today (Credit: Getty Images)
But are culture-bound illnesses really just the result of differences in labelling? Another tantalising possibility is that the society we live in can actually shape the way we get sick.
Physical vs psychological pain
It turns out there is an invisible global divide in the way people experience distress. In the US, the UK, and Europe – at least in the 21st Century – it tends to occur in the mind, with symptoms like sadness, anger or anxiety prevailing. But this is actually pretty weird. In many parts of the world, in countries as diverse as China, Ethiopia and Chile it manifests physically instead.
For example, the most up-to-date edition of the DSM describes a panic attack as “an abrupt surge of intense fear or intense discomfort”. However, in Cambodian refugees, the symptoms tend to centre around their necks instead. Many non-Western mental illnesses, such as koro and Hwa-byung, fit this pattern of perceiving physical symptoms. The divide even extends to the way people in certain societies respond to exercise or surgery; where it’s more usual to experience physical pain, it’s more likely.
In contrast, mental illnesses that involve the perception of pain are rare in the Western world, and hotly debated. Some scientists think chronic fatigue syndrome and fibromyalgia fit into this category, though this is controversial.
In fact, it’s been known for years that our beliefs can have a powerful effect on the way we feel – even on our biology. One example is “Voodoo death”, in which a sudden demise is brought on by fear. In a famous case documented by an early explorer in New Zealand, a Maori woman accidentally ate some fruit from a place that was considered taboo. After announcing that the chief’s spirit would kill her for the sacrilegious act, she died the very next day.
Whether someone could bring about their own death though fear alone is not clear. (Read more about the contagious thought that could kill you.) But there is strong evidence that our thoughts and feelings can have a tangible physical impact, such as when a patient expects a medication to have side-effects, and therefore it does – known as the nocebo effect.
“I would say that there are definitely instances where the meaning that is attributed to experiences actually changes biologically what that experience is,” says Bonnie Kaiser, an expert in psychological anthropology at the University of California, San Diego. She gives the example of the illness kyol goeu, literally “wind overload”, an enigmatic fainting sickness which is prevalent among Khmer refugees in the US.
In their native Cambodia, it’s commonly believed that the body is riddled with channels that contain a wind-like substance – and if these become blocked, the resulting wind overdose will cause the sufferer to permanently lose the use of a limb or die. Out of 100 Khmer patients at one psychiatric clinic in the US, one study found that 36% had experienced an episode of the illness at some point.
Bouts usually proceed slowly, starting with a general feeling of malaise. Then, one day, the victim will stand up and notice that they feel dizzy – and this is how they know that the attack is starting. Eventually they’ll fall to the ground, unable to move or speak until their relatives have administered the appropriate first aid, which usually consists of massaging their limbs or biting their ankles.
While medications are helpful for a lot of people, those with certain cultural beliefs might be more comfortable with treatments like psychotherapy (Credit: Science Photo Library)
Kaiser points out that when most people experience light-headedness, they just shake it off. But if someone interprets that feeling as signalling the start of a kyol goeu attack, they think: “Oh my gosh, something terrible is happening.”
“They really attend to it and they panic,” she says.
The meaning that’s attributed to the feeling of dizziness changes everything. “Fundamentally the actual experience in the body becomes very different,” says Kaiser. “So, to me, this isn't something that has a different name in different places – this illness just doesn't exist in some places. The very biology of that experience is affected by the culture.”
According to Kaiser, in reality, it’s likely that for many mental illnesses, there is both a difference in the way people interpret the same physical experiences, and a positive feedback loop which allows their cultural ideas to shape how they manifest.
Revising Western illnesses
As our understanding of culture-bound illnesses has improved, some psychologists have begun to question whether certain Western mental health conditions fit into this category too. Though certain disorders appear to be universal – schizophrenia occurs in every country on the planet, at a relatively constant rate – this is not true for others. Bulimia is half as common in Eastern cultures, while pre-menstrual syndrome (PMS) is virtually non-existent in China, Hong Kong and India. It’s even been argued, somewhat controversially, that depression is an invention of the English-speaking world, stemming from the misguided notion that it’s normal to be happy all the time.
In the modern era, it would be naive to think that the mental illnesses we suffer from are independent of our way of life. “I think there's a tremendous arrogance in the way that we universalise these mental illnesses and don't see them as socially and historically specific,” says Aho, pointing out that attention deficit disorder (ADD) was only added to the DSM in 1980. “It's clear that children have a more difficult time paying attention now, because they're bombarded with sensory stimulations and their existence is largely mediated by screens. And so it's not as if we’ve only just discovered some discrete medical entity – you can see the way in which technology is shaping the mental and emotional and behavioural lives and children.”
Regardless of their cause, in an increasingly mobile world, some experts are concerned that culturally specific illnesses aren’t being recognised by mental health professionals. “In East Asian cultures, the vocabulary and language that people use to express their distress and symptoms is quite different,” says Sumin Na, a psychologist at McGill University. This means that when East Asian people migrate to places like North America, it’s often not clear when they need help.
Khmer refugees in the US often suffer from the fainting sickness kyol goeu, or "wind overload" (Credit: Getty Images)
“For instance in a lot of Western society, I think we see depression and anxiety as a chemical imbalance. And that leads us to seek help through our doctor and getting medication,” she says. “But in East Asia it’s seen as more of a social or spiritual or a family concern – so people might seek spiritual help or, you know, find ways to resolve family conflict.”
In order to get people the help they need, Na says it’s important to understand a patient’s backstory – the cultural norms where they come from and the loss of power and privilege they might have experienced when they moved, which can often lead to mental health problems down the line. “I think we also have to try to let go of what we think is 'correct' knowledge of mental health and mental illness and not to get really stuck on [them] or the DSM-5 as the only way of understanding and labelling mental illness,” she says.
Equally, it’s unreasonable to expect the same treatments to work for everyone. Na suggests that, while medications are helpful for a lot of people, those with certain cultural beliefs might be more comfortable with things like psychotherapy.
In an era that’s seeing drastic losses in diversity of virtually every other kind – from species to languages, it’s been suggested that we’re standing on a precipice, potentially about to lose our range of mental illnesses too. In the book “Crazy Like Us”, the author Ethan Watters describes how we’ve spent the last few decades slowly, insidiously Americanising mental illness – shoehorning the colourful array of emotional and psychological experiences that exist into a few approved boxes, such as anxiety and depression – and “homogenising the way the world goes mad”.
In the process, not only do we risk missing out on diagnoses and foregoing the most appropriate treatments, but the opportunity to understand how mental illnesses develop in the first place.
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