Phobias: Fighting the Fear. Helen Saul

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      The anxiety system can go wrong, of course, and we would all like to banish the misery of panic attacks, obsessional behaviour or phobias. Successful treatment for these problems can revolutionise lives and nobody wants to get in the way of this. But evolutionists insist we would benefit from taking a step back and looking at why there is so much anxiety in society. They challenge the prevailing view of anxiety as a wholly negative experience. On the contrary, they say anxiety is a prime motivator, a positive drive, a force for good. It prompts us to achieve at work, to guard our reputation and to keep our families together.

      We do not doubt that other animals need the ability to recognise and respond to threats. All living things face danger and must react appropriately if they are to survive. Creatures have a fascinating array of defence mechanisms, each specific to the threats they most commonly encounter. The chameleon changes colour to blend in with its surroundings and hide from potential attackers. A threatened squid squirts ink at its aggressors. Antelope simply run away from lions. Moths are preyed on by bats and have become experts in bat-frequency signals. They monitor the signals continuously and map the direction of their predators’ flight. Only if the bat is heading directly for it does the moth snap its wings shut and fall, as if dead, to the ground. Familiar reactions like these have been sufficient, not for every animal to survive, but to keep the species going.

      The intensity of the reaction also has to be appropriate since animals use up precious resources when trying to defend themselves. An antelope that is too ready to give up grazing and run will soon become undernourished; squid do not have unlimited ink. Even the simplest creatures have remarkably sophisticated responses, as demonstrated by American biologist Herbert Jennings, working in Europe at the turn of the century.

      Jennings was interested in the ordered and elegant lifestyle of a tiny pond animal called a stentor. A stentor is only one cell big, a trumpet-shaped creature, attached by a ‘foot’ to a rock on the water bed. It has a tube at its base which can provide shelter, and the trumpet is an open pouch at its free end for feeding. Hairs around the edge of the pouch waft in food particles.

      Jennings used carmine, a natural red dye extracted from the cochineal beetle. It can be an irritant even for humans and is certainly toxic to tiny animals like stentor. He added carmine to the water tank in which the stentor was living, and simply watched to see what happened.

      The stentor did not at first react to the carmine in the water, but then decisively bent away from the oncoming red specks. The gesture is normally enough to keep it out of trouble in the peaceful conditions at the bottom of a pond. It costs the animal little to try, and it can continue feeding even as it defends itself. In Jennings’s experiment, the stentor bent this way three or four times, and when the strategy did not work, demonstrated a second line of defence. It suddenly pushed its pouch out in the opposite direction in an attempt to dislodge any poisonous particles around the mouth. Again this failed, as Jennings continued to drop carmine into the water. Red particles settled on the pouch and a few more similar moves by the stentor proved futile.

      Drastic measures were called for, so the stentor retreated. It contracted and moved down into the tube at its base. It waited there for a time but could not wait for ever because a single cell does not store much energy and it cannot feed in its bolthole. It moved tentatively upwards out of the tube, but found the water still full of carmine and had to force itself back down again. It advanced to test the water a couple more times but when conditions had not improved, the tiny creature risked its remaining precious energy, contracted violently, dragged its foot away from the rock and floated away in search of an uncontaminated spot.

      Experiments like this have been given new significance by the latest thinking on the adaptive and positive role of fear. A one-celled creature like the stentor has a graded response to a threat, from simply swaying away from the toxin, to pulling up its foot and drifting into the unknown. Stentor allocates its resources meanly so that only the minimum is used to meet a threat. How much more complex, then, might our own reactions to danger be? And could they be built on similar principles?

      People do not function in the same way as protozoans, but some of nature’s rules are universally true. A great deal of our knowledge of human genetics, for example, is derived from study of the fruit fly, Drosophila melanogaster. Our genetic material is the very template from which we grow, and yet most of it can be found in a fly. As Oxford Professor of Physiology Colin Blakemore once rather flippantly pointed out we probably share 70 per cent of our genes with a garden lettuce.

      Biologists discovered in 1972 that human cells can apparently commit suicide for the greater good of the whole body. Cells normally receive signals from neighbouring cells telling them to keep going, and should these stop, they die. Cell death is part of the normal development of a foetus in the womb. Babies develop with webbed hands and feet but the skin between the digits normally retreats before they are born. The cells in this skin die, they ‘commit suicide’ and allow babies to be born with perfectly separated fingers and toes. When cell suicide was first described, it was assumed to be relevant only to the highest creatures since a single-celled organism cannot benefit from its own death. Twenty years after the initial discovery, though, researchers found that single-celled creatures do indeed die in this way. They apparently ‘lay down their lives’ for the good of their community.

      This is just one of many biological similarities between creatures of very different appearance and classification. There is obviously a big difference between the death of a few cells and an all-pervading feeling of fear, but both could be essential for healthy development. Careful observation of animals might help scientists ask more relevant questions about humans. For example, an obvious feature of animals’ fear is that it is necessary. If stentor does not react to a toxin, it dies. If the antelope does not run from the lion, it gets eaten. Max Klein lacked normal fear and stood to damage himself socially, financially and physically. All animals need to be able to respond to danger. But how does that help us understand the common phobias?

      Age-Old Anxieties

      A mixed bunch of academic publishers, scientific editors and advertising sales staff ate dinner together at the end of a conference. One editor was regaling the table with tales of her previous career as an Avon lady. She lost one of her clients, she said, when she took a swipe at the woman’s budgie with her cosmetics bag. Everyone looked up, amazed. ‘It was coming straight at me,’ she said, by way of explanation. This confident, bright young woman had ornithophobia and was not going to stay in the same room as a free bird.

      One of the sales staff was listening with particular interest. ‘I know exactly how you feel,’ he said with feeling. He was afraid of butterflies and moths, and they started discussing the intricacies of the unpleasantness of wing flapping. Suddenly other diners were vying to compare the strength of their fears. His boss chipped in with a fear of heights and a publisher managed both a fear of spiders and of flying.

      The conversation unearthed five phobias in four people among the twelve at the table. Doubtless a psychologist could have found more by interviewing us individually – those mentioned were specific and without much stigma attached – but even this tiny straw poll was telling. The phobias discussed so freely in the restaurant were all directed at threats in the natural world.

      No scientist would be impressed by the dubious methods of this survey, but the results are surprisingly reproducible. Whenever a group starts talking about phobias, notice the fears people describe. Occasionally someone has a weird phobia of buttons, cotton wool or wallpaper, and if they do this may dominate the conversation. But most people fear a limited range of creatures or situations. They fear spiders, snakes, the dark, open or closed spaces; creatures and situations that pose few real problems in the West today but which could be dangerous СКАЧАТЬ