The Science of Fear

I am going to dust off the cover of a book that has been on my bookshelf for over a decade, but which is as relevant today as when first published.

Daniel Gardner, The Science of Fear, Penguin Group, 2008.

Gardner discusses, in easily understandable layperson terms, scientific evidence and theories regarding the psychology of fear. The main theme of the book is that we humans are often irrational when it comes to our fears. The book was written long before the COVID pandemic outbreak, but provides extensive scientific information that is directly relevant to our current situation. Consider the fact that millions of Americans are currently afraid to be vaccinated for protection against COVID. This is the case even though only, at most, a few thousand out of millions have died from being vaccinated. For a rational person, those risks associated with being vaccinated pale in comparison to the risks of dying if one happens to be unlucky enough to become hospitalized with COVID. To date there have been over 600,000 deaths in the USA from COVID, and for those hospitalized with the disease the odds of dying are something like 99 to 1 when comparing those unvaccinated to vaccinated.

This kind of a mass irrational fear is not new. Science of Fear provides numerous examples of irrational fear behavior. Here are a few that might whet your appetite to read the book:

1. Many tremble at the thought of a nuclear reactor, but will pay large sums of money to fly somewhere distant to lie on the beach and soak up radiation emitted by the sun. The accident at the Chernobyl, the worst nuclear reactor accident in history, killed about 9,000 people total, but more than 10,000 are killed every year from sun cancer.
2. Almost 3,000 people died from the terrorist attack on 9/11/2001, but an additional 1,595, died in the years following 9/11 because they became afraid of flying and chose to drive instead.
3. When a group of cancer patients was told that a particular treatment would give them a 68% chance of being alive 1 yr later, 44% opted for the treatment, but when informed that there was a 32% chance of dying, only 18% chose to have the treatment.
4. Christmas tree lights kill more people each year than shark attacks.

Why are we humans so susceptible to irrational fears? One reason is that media companies (television and talk radio) have learned how to ramp up their ratings by convincing us what we should fear. Similarly, many corporations have learned how to make money by exploiting fear, and politicians have learned to play the fear card to get elected.

But that is not the entire story. We need to also ask why it is so easy to sell irrational fear. The answer to this question requires looking at scientific research that applies over two different time periods. One set of research looks at the organization of brains and behaviors of modern humans. Psychologists have documented irrational behaviors related to fear, and neuroscientists have discovered neural circuits present in our brains that are responsible for some of those fear responses. A second set of research carried out by evolutionary psychologists looks farther back in time to ask what led to the evolution of those neural circuits in our brains. Gardner summarizes both kinds of scientific research, and I will highlight a few of the main findings.

There are two brain systems humans use to make decisions, referred to colloquially as Gut and Head. The brain system based on Head works slowly, examines the evidence, and tries to calculate probabilities, although as demonstrated in examples throughout the book, it is often woefully bad at doing this. But the system based on Gut works entirely different. It works lightning fast, and without our conscious awareness, to arrive at a snap judgment. A decision that is based on Gut is often impossible to explain in words. You don’t know why you feel the way you do, you just do. Its decisions are based on rules of thumb called heuristics. Heuristics were put into our brain by evolution because they worked quite well in the environment in which humans evolved. Very few of us modern humans spend our days stalking antelope and avoiding lions, but these neural circuits are still present in our brains and can be exploited by the merchants of fear.

Here is an example of the operation of a heuristic called the anchoring rule: Suppose you had recently been exposed to the statement, “Recent figures suggest some 50,000 pedophiles are prowling the internet at any one time.” It doesn’t matter if this statement is accurate or not (and the book provides ample evidence that it probably is not). The very fact that you have been exposed to that statement will influence your judgment if you are subsequently asked how many pedophiles are likely to be on the internet. The estimate you give will be substantially higher than it would have been if you had been exposed to the statement “Recent evidence suggests 500 pedophiles are prowling the internet at any one time.” In other words, you judgment has been anchored closer to 5,000 after being exposed to the first statement, and closer to 500 after being exposed to the second. If you are “in the business” of making people afraid of the influence of pedophiles on the internet, and you have no clue about how many pedophiles there really are on the internet, better to pick (make up) a large rather than a small number. That appears to be the primary factor that accounts for the fact that the “50,000 pedophiles” number is reported widely, even though there does not appear to be any empirical support for this number.

Another heuristic is called Representativeness (Rule of Typical Things): The Gut is a sucker for a good story, and if a story has a coherent narrative we will consider it to be plausible even if it defies logic based on probabilities. Elaborate scenarios tied together by a common theme are particularly believable, the more elaborate the more believable. This is one factor that accounts for how susceptible humans are to conspiracy theories. Gut is good with stories but does not care about facts, so companies or politicians who want to sell us something bombard us with stories instead.

The affect heuristic refers to the fact that Gut gives us an immediate assessment of whether something is “good or bad”. This unconscious judgment then colors all of the subsequent assessments we make with Head. Fear of cancer is a good example of something that makes us probability blind because the fear overwhelms any influence of the actual probabilities involved. Another example is fear of nuclear radiation.

In general, it was probably adaptive from an evolutionary point of view for our ancestors to conform to the group. However, in our high tech society where most of us do not have enough technical expertise to evaluate the empirical evidence, following the herd is often not a rational decision. Our society is rapidly losing the ability to trust the judgments of experts. Skepticism is healthy, but our society is in danger of moving from skepticism to cynicism, and the sneer of the cynic, especially when combined with appeals based on fear, can mutate into irrational distrust of all authority. We end up left with global warming deniers, and the anti-vaccine movements. Whenever large enough numbers of people begin to hold a common belief, whether rational or irrational, the herd instinct kicks in, and then the confirmation bias kicks in, and then group polarization kicks in and this means the belief (even if irrational) can go on forever, regardless of what the evidence shows.

Science of Fear makes an argument that based on objective historical statistics, we are the safest, healthiest, and wealthiest humans who ever lived, but you would be hard pressed to know that because Gut is busy listening to good stories about things we should be afraid of and doesn’t really care about objective numbers or facts.

Ron Boothe

psyrgb@emory.edu