Skip to main content

Verified by Psychology Today

Genetics

Where Do Fears and Phobias Come From?

Blame your genes and your life experiences.

Millions of individuals experience debilitating levels of anxiety, with phobias being the most common anxiety disorder. Sub-categories of phobias include:

sethink/Pixabay
Source: sethink/Pixabay
  • Animals, with spiders and snakes being among the most common
  • Natural environments, like heights or being in a thunderstorm
  • Blood, injections, and injuries, such as getting a shot, having blood drawn, or seeing blood
  • Other situations, such as flying on an airplane or riding in an elevator

What's to blame for our fears? Are we destined to have fears and phobias based on the genes we inherit or are our experiences to blame?

A recent review combed through over 4,000 studies to identify all the relevant research in this area, which turned out to be a total of 10 articles. ​

Based on their summary of the data, genetic differences among individuals had a big effect on the development of phobias. For example, genetic variation accounted for 45 percent of individual differences in animal fears, and 41 percent of differences in blood-injection-injury fears.

tpsdave/Pixabay
Source: tpsdave/Pixabay

While these numbers are considerable, they also reveal that non-genetic effects explained most of the differences in fears and phobias. Specifically, the researchers found that individual experiences were the strongest predictor of fears and phobias—things like being bitten by a dog or getting caught in a dangerous thunderstorm.

Based on these data, we might conclude that both "nature" and "nurture" play a role, and that nurture seems to be the more important factor.

However, the authors explain why the story is probably more complicated, and illustrate why the "nature-vs-nurture" dichotomy is an oversimplification. They point out that people vary in their responses to scary events, with some of us developing a strong fear and others being relatively unphased by the event.

Parents often see these differences even between their kids, who on average share 50 percent of their genetic information (unless they're identical twins). For example, one child might be afraid to climb a chair after falling one time, while his sister might keep climbing the furniture no matter how many times she falls (much to her parents' chagrin).

Thus even "obvious" explanations for a person's fear might not be right, or at least might not be complete. We might explain a person's fear of water based on a frightening experience he had as a child, which is part of the story. But we might not realize that that experience was amplified by the person's tendency to develop fears after that kind of experience. The authors note that this tendency is determined at least in part by our genes.

Whatever the causes of phobias, the good news is that they respond amazingly well to the right kind of treatment. A single session of exposure therapy (average length of about two hours) can relieve the vast majority of phobias, with as many as 90 percent of people being "much improved or completely recovered" an average of four years later. Treatment involves gradually confronting one's fears in a relatively controlled setting.

If you have a phobia that's getting in the way of living your life, it's worth looking for a therapist who specializes in this kind of treatment.

Facebook image: mimagephotography/Shutterstock

LinkedIn image: tommaso79/Shutterstock

advertisement
More from Seth J. Gillihan PhD
More from Psychology Today