Creepy crawlies and why we fear them

Some fears and phobias we learn, but some, we are born with.

Most of us have never seen a poisonous snake or spider, except perhaps on a wildlife documentary, our fears temporarily put at rest by the reassuringly smooth voice of Sir David Attenborough. Yet a large number of people find these creatures repulsive. There are plenty of other dangerous animals in the world that could harm or even kill us, but no lion, shark or wolf incites the same fear and loathing as a snake or a spider.

The truth is, many of us are born with an innate fear of anything reptilian or eight legged. This is because some animal phobias are deep rooted in our brains – rats for instance are unconsciously associated with plague or rotting food, but even they don’t excite the same terror associated with the sight of an arachnid or ophidian.

Even babies who have never been exposed to the idea that snakes and spiders are nasty creepy crawlies don’t like pictures of them. These reactions have been fixed in our brains for millennia, and for sound evolutionarily reasons. The fear has been passed down through our genes because of millions of years of experience.

Researchers at the Max Planck Institute for Human Cognitive and Brain Sciences in Germany and the Uppsala University in Sweden studied why stress reactions occur when very young children see a spider or snake.

They showed 16 six month-old children two sets of animal pictures – the first set consisted of eight photographs of spiders and flowers, while the second set consisted of eight photographs of snakes and fish. Each of the pictures had the same corresponding colours – the colours of the flowers corresponded to the colours of the spider, and the colours of the snake corresponded with the colours of the fish.

The researchers measured the infant’s pupil dilation and found that their pupils significantly enlarged when they saw the snakes and spiders. This is a distinct sign that they felt stressed looking at these animals.

In developed countries, between 1% and 5% of people are affected by arachnophobia or ophidiophobia, the fear of snakes.  Arachnophobia can develop into a level of anxiety that will limit a person’s life. Some people can’t even enter a room unless it’s been declared spider-free. My experience after living in South Africa for so many years is that the black population harbour not just a fear, they have a morbid dread of snakes – they are terrified of them. And no big surprise, because around 30,000 people are killed in sub-Saharan Africa every year, out of a total of more than 100,000 worldwide!

Until recently, it wasn’t entirely clear whether these fears were inborn or learned. Some researchers assumed they were learned when we were children, most especially from adults, while others thought they were innate. Earlier similar experiments had always been conducted with adults or older children and only tested whether subjects were able to spot spiders and snakes faster than harmless animals or objects, rather than a direct physiological fear reaction.

This latest research has found that the fear reaction happens in infants as young as six months-old, when they are still too young to have had the opportunity to learn these animals can be dangerous. Even the youngest babies appeared stressed – confirming the fear of snakes and spiders is of evolutionary origin. Survival mechanisms in our brains allow us to identify objects and to react to them quickly. Primates also have this ability and there’s plenty of evidence to support that dogs and other higher mammals are also naturally wary of snakes.

This inherited stress reaction predisposes us to recognise these animals as dangerous or repulsive, and can develop into real fears or phobias.

Any fears expressed about spiders or snakes by parents or a genetic predisposition for a hyperactive amygdala – important for estimating hazards – can mean that increased attention to these creatures can turn into an anxiety disorder. Previous studies have shown that babies don’t associate pictures of rhinos, bears or other theoretically dangerous animals, with fear.

Snakes and spiders on the other hand have been around much longer than today’s dangerous mammals – unlike modern risks such as flying or being run over by a car. From an evolutionary perspective, they’ve only existed for a short time, and there’s been no time to establish reaction mechanisms in the brain from birth.

There are still ways to help people overcome their fears. Hypnotherapy is one obvious solution, along with mindfulness and CBT. However, a healthy respect for snakes and spiders is probably a good thing, particularly if you live in countries that are also home to poisonous snakes and spiders.

 

Copyright Andrew Newton 2017. All rights reserved.