Genes or environment?
But before we can be sure that conditioning is the main reason, we need to ensure that genetic factors are not involved too. In 2003, John Hettema at the Virginia Institute for Psychiatric and Behavioural Genetics and his colleagues conducted twin studies to tease apart genetic factors.
Identical twins have identical DNA but tend to live in different environments in adult life, which allows researchers to find out how genes affect behaviour. When Hettema recorded the responses of twins to “fear-relevant” images (spiders, snakes) compared to “fear-irrelevant” images (circles, triangles). Statistical analysis of the results revealed that genetic influences were “substantial”, which means that arachnophobia is inheritable. You need not necessarily experience spiders to be fearful of them.
So, to my dissatisfaction, arachnophobia is here to stay. But there may be a simple technique to reduce the fear these bugs cause. In 2013, Paul Siegel at the State University of New York and his colleague published a study that helped volunteers lessen their arachnophobia.
They first split the volunteers into phobic and non-phobic groups, based on simple spider-fear tests. After a week of doing these tests, both the groups were then given exposed to images of flowers or spiders, but the exposure was for such a very short time.
The idea was that people can’t recognise the images consciously, but it has an effect on their subconscious. When the spider-fear tests were carried out on both these groups again, those who feared spiders had become less afraid.
While other general conclusions are hard to draw from the literature on arachnophobia, arachnologists like me should rejoice at the results of Hettema’s study. If nothing else, at least sharing images of spiders may help reduce arahnophobia.
Chris Buddle does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.