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The Fear Factor

“Good for Nothing” in the UK market

In this “compelling scientific detective story,” a leading neuroscientist looks for the nature of human kindness in the brains of heroes and psychopaths (Wall Street Journal).

At fourteen, Amber could boast of killing her guinea pig, threatening to burn down her home, and seducing men in exchange for gifts. She used the tools she had available to get what she wanted, and, she didn’t care about the… damage she inflicted. A few miles away, Lenny Skutnik was so concerned about the life of a drowning woman that he jumped into the ice-cold river to save her. How could Amber care so little about others’ lives, while Lenny cared so much?

Abigail Marsh studied the brains of both psychopathic children and extreme altruists and found that the answer lies in our ability to recognize others’ fear. And as The Fear Factor argues, by studying people who demonstrate heroic and evil behaviors, we can learn more about how human morality is coded in the brain.

A path-breaking read, The Fear Factor is essential for anyone seeking to understand the heights and depths of human nature.

Praise for the Book

“A brilliant, beautiful, and important book about the things that make some of us angels, some of us devils, and all of us human. You won’t be able to put it down.”

— DANIEL GILBERT, New York Times bestselling author of Stumbling on Happiness

“Let Abigail Marsh guide you on a riveting ride through your own brain. With lively writing and an impressive command of science, she shows how sensitivity to fear can be both a weapon of evil and a force for good.”

— ADAM GRANT, New York Times bestselling author of Originals, Give and Take, and Option B (with Sheryl Sandberg)

The Fear Factor reads like a thriller. Abigail Marsh takes us through the groundbreaking research that has thrown light on two of the most fundamental traits of human beings: extreme selfishness and extreme altruism. Page after page, she shows convincingly that the capacity to perceive and identify fear and, consequently, to feel empathy as one would for a child in danger, is the key factor that makes us behave as a psychopath or as someone who joyfully gives a kidney to a stranger. One of the most mind-opening books I have read in years.”

— MATTHIEU RICARD, Author of Happiness and Altruism: The Power of Compassion to Change Yourself and the World

“Beautifully and engagingly written, yet not compromising on science. Abigail Marsh has written a page turner that takes you meticulously through the scientific evidence for why altruism exists, while fooling you into thinking that you are reading a detective novel. This is essential reading for anyone interested in why people vary in their capacity for empathy and love.”

— ESSI VIDING, PHD, Professor of Developmental Psychopathology, University College London

“Marsh’s dynamic prose brings scientific studies and technical topics to life… Those who seek to comprehend the origin of fear, altruism, and elements of human nature will find this book a key factor in their increased understanding.”


“This compelling scientific detective story spirals outward into realms that affect everyone. Best of all, [Marsh’s] writing style is vivid and personable.”


“Recommend this fascinating text to readers of pop psychology and true crime fans who wish to better understand the minds of potential criminals.”


“Though we’re all riddled with contradictions, certain principles help explain who we are. Those principles are rooted in neuro-chemical realities, not just of the human brain but also the brains of other species with which we share more than we realize. Look a little deeper, and you’ll see how we’re all connected. The Fear Factor is a fine example of a book that looks deeper, showing how an ancient part of the brain— central to our emotional lives—plays a pivotal role in who we are and what we do. It’s a sharp analysis sprinkled with relatable examples, and an excellent brain book…”


“Marsh posits that we all exist somewhere along the same empathy spectrum, with psychopaths at one end and “extreme altruists”–people who, for instance, donate a kidney to a stranger–at the other. The key, she argues is our response to another’s fear; her book is deft enough to be chilling at times, infectiously optimistic at others.


“Abigail Marsh is a fantastic writer and a pioneering scientist in the field of neuroscience… Highly recommended to those who enjoy neuroscience, the human condition and exceptional cases of the brain going haywire.”


The Fear Factor is a fascinating tour of altruism research, all the better for being sprinkled with anecdotes about Marsh’s life, career and unforgettable research subjects. As well as the extremes of human nature, Marsh says plenty that is of relevance to those of us in the middle of the bell curve, including how we can strive to be more altruistic in our everyday lives.”


“Fear Factor provides an illuminating dive into the science behind both altruism and psychopathy, promising an entertaining read for scientists and laypeople alike… A groundbreaking read, The Fear Factor is essential for anyone seeking to understand the heights and depths of human nature.”

— PASTE Magazine

“…All readers experiencing our national culture of fear, rage, and (perhaps in some cases) a rush to judgment will benefit from this examination of the importance of fear, empathy, humility, and the mysterious physiological conditions that can trigger (organically or not) the extraordinary altruist in all of us. The psychopathy stories are dark and disturbing, the altruism stories are extraordinary, and somewhere in all these shades we can find ourselves.”


Message Dr. Marsh