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30 October 2012, 6.08am AEST

Explainer: what are phobias?

What makes a fear a phobia? jasonbolonski/Flickr.

A life without fear sounds idyllic but it would be no paradise. Fear protects us from present danger, alerts us to future threat, sharpens our minds and blunts our selfishness. Friedrich Nietzsche once said that fear is the mother of morals, and people who lack it do indeed tend to be nasty, brutish and short-lived.

While useful to a point, people often suffer from an excess of fear. Although many of us are afraid of snakes, spiders, heights and blood, when these normal fears are taken to extremes they become phobias.

To qualify as a phobia, a fear must be lasting, intense and seen by the sufferer as excessive and irrational. It must also be a source of distress or impairment in the person’s occupational life and social relationships.

Phobias affect about 10% of the general population at some point in their lives, with women affected twice as commonly as men.

What are we afraid of?

Phobias commonly involve objects and situations that were realistic dangers for our distant ancestors: poisonous or vicious animals and invitations to injury. As a result, many people are terrified of things that no longer pose a contemporary threat.

Ancestral fears are learnt with remarkable ease. One study found that young rhesus monkeys acquired a fear of snakes when they viewed a film of older monkeys acting terrified in the presence of a snake, but did not come to fear flowers when they viewed monkeys going ape in the presence of a blossom. Fears related to things that were threats to our forebears are more easily acquired than others.

Deliciously scary? EuroMagic/Flickr.

Although many common phobias are of this ancient or “prepared” kind, the spectrum of human fears is astonishingly broad. The clinical literature records phobias of rubber bands, dolls, clowns, balloons, onions, being laughed at, dictation, sneezing, swings, chocolate and the wicked, beady eyes of potatoes. Unusual fears are particularly common among people with autism, who have been known to dread hair dryers, egg-beaters, toilets, black television screens, buttons, hairs in the bathtub and facial moles.

It is hard to see the evolutionary threat posed by these innocuous things. As Stanley Rachman, the psychologist who treated the chocophobe wrote, “it is difficult to imagine our pre-technological ancestors fleeing into the bushes at the sight of a well-made truffle”.

How do phobias develop?

Given that many modern phobias make little logical sense, it is interesting to explore how they emerge. There are three main identified ways that phobias come about: a terrifying personal encounter, witnessing another person’s fright, and receiving threatening information. A person might acquire a spider phobia after a close encounter in the shower, after seeing a sibling run screaming from an infested room or after being told that spider bites cause you to turn purple and die.

Only a small minority of people will develop phobias after common experiences such as these. Those who had inhibited temperaments in childhood and neurotic personalities in adulthood are more vulnerable, and this vulnerability has a substantial genetic component.

A study that followed a sample of young women over a 17-month period found that those who developed phobias tended to have more pre-existing psychological problems, poorer coping skills and a more pessimistic mindset than their peers.

Let’s consider one odd but surprisingly common aversion, the fear of frogs.

One published case documented a woman who developed ranidaphobia, as it is known, after running over a knot of frogs with a lawn-mower. Paralysed by fear and tormented by amphibian dreams, she was persecuted every evening by an accusing chorus of survivors on a nearby riverbank.

In another case, a Ghanaian schoolboy developed his phobia when he stepped on a frog while touching itchy leaves. After his brother told him that frog urine could cause itching and a painful death, the boy became paralysed with the fear that frogs were hiding in his bed.

This fear was put to productive use elsewhere in west Africa, with one anthropologist reporting that bed-wetting children were frightened into bladder control by having a live frog attached to their waists.

Ranidaphobia is surprisingly common. Ltshears/Wikimedia Commons.

What gives these puny creatures – with big eyes and scrawny, hairless bodies – their power to inspire fear and trembling? They pose no realistic threat to life: phobic individuals understand that in an encounter with a frog they are unlikely to be the one to croak.

The fear of frogs is viscerally unreasonable. To many people it reflects the frog’s slimy, skin-crawling ickyness. To others, it is the creature’s propensity for sudden movement, a trait it shares with another tiny source of terror, the mouse.


Luckily for phobia sufferers, treatment is generally quick and effective. Cognitive-behaviour therapists have an assortment of techniques for confronting fears and challenging the avoidance and thinking biases that sustain them. Usually these methods involve progressive exposure to the feared object or situation up the steps of a “fear hierarchy”, from relatively nonthreatening encounters to the most terrifying.

These “behavioural experiments” are often supplemented by relaxation techniques, modelling of exposure by the therapist and correction of catastrophic thoughts.

In another case of ranidaphobia, a young nursing student, fainted in a biology class when her laboratory partner severed a frog’s spinal cord (“pithing”). A course of therapy was commenced in which she repeatedly viewed a videotape of the operation and practised relaxation techniques.

Such was the success of the treatment that in a single sitting immediately afterwards she was able to deliver electric shocks to one frog, pith another and cut open the abdomen of an anaesthetised rat, remaining calm even when one frog hopped loose, bleeding profusely from its injuries.

By facing what we dread, under the guidance of a psychologist, we can find freedom from irrational fear.

More on Overdiagnosis.


17 September 2012, 6.25am AEST

Over-diagnosis: the view from inside primary care


OVER-DIAGNOSIS EPIDEMIC – We kick off the second week of this series with Jenny Doust looking at some drivers of over-diagnosis in general practice. It’s easy to dismiss general practice as being about minor illnesses requiring little clinical acumen. We see patients with the common symptoms of life…

Of all the teenagers with flu-like symptoms, GPs need to find the one with a lymphoma in his chest. Joey Yee

OVER-DIAGNOSIS EPIDEMIC – We kick off the second week of this series with Jenny Doust looking at some drivers of over-diagnosis in general practice.

It’s easy to dismiss general practice as being about minor illnesses requiring little clinical acumen. We see patients with the common symptoms of life – coughs, fevers, backache and abdominal pain. Most of these are transitory and, for the large proportion, medical intervention makes little difference.

The diagnostic skills of a general practitioner, however, need to be as acute as those of House MD. Among all the children we general practitioners see with diarrhoea, we need to be able to pick the one with Crohn’s disease requiring urgent surgery. Among all the women who complain of feeling tired, we need to isolate the one who has life-threatening Addison’s disease. And among all the teenagers with flu-like symptoms, we need to find the one with a lymphoma in his chest.

These are all patients I have seen during my time as a general practitioner and they remind me constantly to take every person who walks through my door seriously.

Missing diagnosis

The most common reason general practitioners are sued is because of missed diagnoses. Missed diagnoses also invoke a strong sense of professional failure. So how can general practitioners manage in this sea of uncertainty?

One way is to perform more tests. This is also popular with patients, who perceive that tests ensure nothing serious is missed. What is not well understood by patients (and sometimes also by clinicians) is the potential harm from testing.

The most obvious harm is the cost and resources required; we would quickly overwhelm the health system if we performed an MRI on every patient with back pain. A strong system of primary care results in a health-care system that’s both more efficient and less costly because primary-care physicians are skilled at filtering those with severe disease needing further tests, from those with self-limiting illnesses.

But even in Australia, with its highly trained general practice workforce, this skill is often under-appreciated.

Harms of testing

Less well understood are the harms due to the inherent inaccuracy of testing. By the laws of statistics, when the likelihood of a disease is very low, most positive test results will be false positives. We see this most clearly in screening programs, where most abnormal screening results will not have the disease on follow-up testing. This causes only minor harm if there is a follow-up test. But it is of much greater consequence if tests are assumed to be accurate and too much faith is put in the results.

The greatest harm from the increased use of testing, however, is not costs, resources or false positives. Rather, it’s the problem of over-diagnosis.

Clinicians and patients both believe that finding a disease earlier in its process means it will be more successfully treated. But there’s increasing evidence that finding disease early or at a milder stage has paradoxical harmful effects, even reducing survival and quality of life.

Wider availability of more sophisticated tests results in “incidentalomas”, incidental findings that would not have otherwise been diagnosed. The detection of thyroid cancers, for instance, has more than doubled in the past 30 years. But most of these diagnoses are incidental findings from imaging.

If the earlier detection of these cancers improved prognosis, you would expect to see a decline in the mortality rate from thyroid cancer. But the mortality rate has sadly been constant in this time.

Looser boundaries

Even more problematic is the widening of the definition of diseases and the lowering of disease thresholds. Examples of expanding definitions include chronic kidney disease, diabetes, and even the diagnosis of cancers, such as breast and bladder cancer.

We assume patients who are now included in the wider definition benefit from treatment as much as those using the old definition. In fact, we are likely to believe that they will benefit more as we have caught the disease early. But all medical treatments cause harm. And when patients with milder disease are treated, it becomes more likely that the potential harm of medical treatment will outweigh the benefits.

Wider disease definitions become self-reinforcing – we find more and so we test more. And because we have now included milder patients in our disease group, we are misled by the perceived improvement in patient survival and the reduction in disease complications in our new patient group.

What now?

Right now, we are in the midst of a perfect storm – a population that is increasingly anxious about health, doctors who don’t want to miss a diagnosis, a pharmaceutical industry that profits from widening the definitions of disease and a health system that rewards over-testing and fails to acknowledge the harms that can result from it.

We have set up a group to look for solutions to this problem, including a conference in 2013, but the answers are far from clear. Given the pervasive nature of over-diagnosis, solutions will need to involve all layers of the health-care system, including policy makers and key clinical opinion leaders.

As a general practice physician, I am hoping we will be able to spend less time labelling patients with an ever increasing number of “diseases” and to spend more time working with them on solving their health problems.