Original Fears

The Truth About Nature, Nurture, And The Origin Of Phobias

Are we passing along our fears or are they there to begin with?

by Natalie Grover
Originally Published: 
Children's emotions and frustration.
Natalia Lebedinskaia/Moment/Getty Images

It’s normal to be afraid of dangers that have long plagued humankind, from heights and falling to snakes and spiders. Evolution would suggest that perhaps babies are born with fear to urge extra caution around these threats. After all, you don’t want a baby playing with potentially poisonous spiders or leaping off a changing table. But recent research in this classic nature vs. nurture debate over phobias suggests that it’s actually more likely that babies are born fearless. Instead of popping out with terror already hardwired into their brains, they quickly learn when to be scared, says David Rakison, an associate professor of psychology at Carnegie Mellon University who researches early infant development.

Evolution has primed babies to learn certain fears very quickly — either through their own experiences or the powers of observation, Rakison says. This is particularly true when it comes to threats that human ancestors have battled over millions of years, such as snakes, spiders, the dark, heights, and enclosed spaces.

When Do Babies Develop Phobias?

Fear begins to emerge when babies start crawling and experiencing the world untethered from their parents, Rakison says. This allows them to fall from heights and get into all sorts of terrifying trouble. But babies can also internalize fears by observing those closest to them. If a parent screams or jumps on a chair when they see a spider or rat, for example, the baby quickly associates the critter with being afraid.

Of course, snakes and spiders aren’t as big of dangers to humankind as they once were, especially compared to modern threats like guns and cigarettes and car accidents. But just because your child has a phobia doesn’t necessarily mean you need to quash it, Rakison says. “It is healthy to be fearful — a child who isn’t fearful of anything is going to get in more trouble than the child who’s fearful too much.”

The Origins Of Phobias For Snakes And Spiders

Phobias of snakes and spiders are some of the most common and intense in the world. About two to three percent of the global population has an extreme fear of snakes, or ophidiophobia. Research shows that it accounts for as much as a half of all animal phobias. But a fear of snakes isn’t natural; it’s learned, studies suggest.

When researchers exposed 48 6-month-old babies to pictures of spiders and snakes, their pupils dilated — a stress response and a sign of arousal and focus. Images of flowers and fish didn’t trigger the same reaction, according to the 2017 study. In other words, babies pay special attention to snakes and spiders. But it’s probably not because they’re afraid of them. Other research has found that toddlers aged 18 months to 36 months don’t act scared around these critters or try to avoid them.

Because older toddlers don’t show fear in response to the real live animals, the fear itself is probably not innate. Instead, babies probably recognize the snakes and spiders as a potential threat, which suggests that they’re prepped to become afraid of them later in life, Rakison says.

If your child is terrified of snakes or spiders, try not to show fear when faced with either creature to avoid reinforcing their panic. Otherwise, the best way to address their phobia is by acknowledging it and providing them with information about the creatures — for example, how they can avoid being bitten by staying away from tall grass where snakes are often found. Empowering your little one with facts can make them feel more in control, and as a result, less scared. This approach also reinforces that in certain contexts, avoiding creepy crawlies is healthy and will protect them.

The Origins Of Acrophobia, Or A Fear of Heights

An iconic experiment in the 1960’s established that infants could perceive depth by the time they learn to crawl. Researchers placed 6- to 14-month-old infants on a platform decked out in a checkerboard pattern. Connected to the platform was a transparent glass surface, and the checkerboard pattern continued on the floor several feet below the glass, creating the illusion of a cliff with a steep drop. The objective of the experiment was to determine how many of the young participants would actually step over the “visual cliff.”

If you set up the experiment right, the drop looks dangerous, Rakison says. “For babies that are not yet crawling, you can put them in the middle of this visual cliff and they don’t show any signs of fear. Babies who have started crawling show a little bit of fear but not very much. Only after babies have been crawling for about a month, and therefore have likely had experiences of stairs and drops and bumps, do they really start to refuse to go across the visual cliff.”

But researchers now believe that this landmark study conflates the avoidance of falling with fear. There is no compelling evidence to support that infants are afraid of heights. They’re just trying not to drop off a cliff, and can you blame them? Like other fears, however, the fear of heights can be learned.

If your child is afraid of heights, give exposure therapy a try. This technique gently exposes your child to the situation they fear little by little so they can become less sensitive to it. This form of therapy can work with all kinds of fears. In the case of a fear of heights, start by looking at pictures of scenic heights, such as mountains, then move on to a tall seesaw, and work your way up from there.

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