What do psychopaths and altruists have in common? According to Abigail Marsh’s eye-opening book, The Fear Factor, one answer is that they both have highly unusual brains – at least in one small but very important area. Deep in the human brain, a couple of inches behind the right eye in most people, is an almond-shaped, evolutionarily-ancient structure that is highly responsive to expressions of fear in other people. This structure is the amygdala. (It has a counterpart in the left hemisphere, by the way, but the right amygdala is the star of Marsh’s show).

Heroes, true humanitarians, and live kidney donors have highly-developed amygdalae, and people with psychopathic tendencies have very poorly developed amygdalae. One consequence of this fact is that psychopaths barely experience fear. More important, they don’t understand why other people do, and they have little or no empathy for people who are afraid.  With little ability to perceive fear in others or to experience it themselves, what’s to stop them from deceiving, abusing, or even torturing others to get what they want?  

At the other extreme, true altruists -- such as living kidney donors who’ve given one of their kidneys to a complete stranger – are great at detecting fear in others, and the empathy they feel when they see another person suffering makes it very hard for them to sit by and do nothing. Whether this means giving up one of their kidneys or overcoming their own terror to save a stranger in distress, people with highly developed fear-detection systems do these kinds of things as if they had no other choice.  We know this, by the way, because of cutting-edge research in behavioral neuroscience, much of which Marsh has conducted herself. If you want to know what those super-magnets called fMRI scanners can tell us about human cruelty and compassion, this book is a good place to find out.   

But the main reason you should read The Fear Factor is not that it explains neuroscience in an accessible way (which it does). Rather, it is that this book offers deep insights – some of them cultural as well as cranial – into the nature of being human. Marsh explains both why all of us can be so selfish and why all of us (well, almost all of us) are capable of acts of great compassion and self-sacrifice.  And Marsh tells this psychological and neuroscientific story in a highly engaging and accessible way. Perhaps just as important, she carefully addresses tricky questions, such as personal responsibility for our good and bad deeds, in ways that reflect her own common sense and empathy.  

To provide just one example of where her book differs from other books on human nature, Marsh reviews research in behavioral neuroscience as well as research in evolutionary psychology that suggest that most human beings are not nearly as selfish as most laypeople – and many psychologists – seem to think. From stories of heroically devoted mother rats and lionesses to stories of families who root for sea turtles making their perilous journey to the sea, this new book will take you on a journey that will make you both smarter and more compassionate. How good is this book? If Mahatma Gandhi and Agatha Christie both got their PhDs in behavioral neuroscience, spent 15 years doing cutting-edge research together, and then jointly wrote a popular science book about it, this is the kind of book they’d be shooting for.       


Brett Pelham is professor of psychology at Montgomery College, MD and author of books such as Evolutionary Psychology: Genes, Environments, and Time (2018). He is also an associate editor at Character and Context.  

Reference

Marsh, A. (2017). The fear factor: How one emotion connects altruists, psychopaths, & everyone in between. New York: Basic Books.