Psychopaths, altruists and the amygdala
In the year 2000, a teenage girl received brain surgery to treat a particularly severe case of epilepsy. When she awoke, she realized something strange: Her brain had started to work a little differently. She became better at reading emotions. When she saw someone in pain or joy, her body reacted far more viscerally than it had in the past.
She had developed “hyper empathy.”
In 2013, a French research team confirmed the now-woman’s claims and published the results in Neurocase: The Neural Basis of Cognition.
The amygdala, one of the brain regions the doctors removed during the surgery, has been associated with empathy in the past. In one study, researchers found that when patients experienced strokes that impaired emotional perspective-taking, the lesions were most commonly found on the right amygdala. In another study, researchers discovered that two patients with amygdala lesions were also unable to properly shift their emotional perspective. Two quantitative meta-analyses — one that looked at studies of emotional empathy and another that focused on perceiving pain in other people — found that the amygdala was regularly activated during moments of empathy.
Looking into the brains of psychopaths
Psychopaths are commonly defined as people who do not experience empathy, but nonetheless understand how other people’s minds works. (It should be noted that “psychopath” is not an official diagnosis and that most people who meet this criteria are diagnosed with antisocial personality disorder.)
How does a psychopath’s brain differ from someone else’s? Researchers have found that when individuals with psychopathy are shown visual scenarios illustrating physical pain — for instance, a picture of a finger caught between a door and the wall — their brains did not behave as expected.
If the participants with psychopathy were instructed to imagine the painful scenario happening to someone else, the regions in their brain associated with empathy (like the amygdala) were under-active. When they were told to imagine that the painful scenario was happening to themselves, however, their brain activity was no different from controls.
In other words, these people lacked empathy for other people but still understood that pain was unpleasant to experience.
Looking into the brains of altruists
What about people who experience more empathy than other people? How are their brains different?
Abigail A. Marsh, Ph.D., a neuroscientist at Georgetown University, led a study to determine how the brains of extreme altruists — or people who regularly go out of their way to commit good deeds — differ from the brains of other people. Extreme altruists don’t simply volunteer at homeless shelters — they live in small apartments so that they can give the majority of their income to charity, adopt dozens of children and risk their physical health for complete strangers.
Marsh and colleagues examined the brain activity of people who donated a kidney to a stranger and published their results in the scientific journal Proceedings of the National Academy of Sciences. They found that these extreme altruists showed greater activity in the amygdala than other people when viewing emotional scenes. The researchers also found that extreme altruists had amygdalae that were larger than usual. (In contrast, individuals with psychopathy have smaller than normal amygdalae.)
What does this mean?
The amygdala appears to be at least partially responsible for how we relate to — and emphasize with — other people. The association isn’t necessarily clear cut, however. For instance, psychopaths have smaller than usual amygdalae, yet a woman who is missing her entire right amygdala demonstrated higher empathy — not lower.
The brain is a highly complex organ with dozens (if not hundreds or thousands) of redundancies and failsafe mechanisms. It’s possible that another brain region is communicating with the amygdala to influence empathy, or that empathy itself is modulated by multiple brain regions at the same time.
In other words, this research — while important — only scratches the surface of how our brain functions. Neuroscience is a new, flourishing field, and it will be exciting to see how our understanding of the mind develops.
The Sovereign Health Group is a residential rehabilitation facility that offers high-quality and comprehensive care for individuals with mental illness, substance addiction and co-occurring conditions. We pride ourselves on staying up to date on neuroscience research and following the development of cutting-edge therapies. For more information, please contact our 24/7 helpline.
About the author
Courtney Lopresti, M.S., is a senior staff writer for the Sovereign Health Group, where she uses her scientific background to write online blogs and articles for a general audience. At the University of Pittsburgh, where she earned her master’s in neuroscience, she used functional neuroimaging to study how the human cerebellum contributes to language processing. In her spare time, she writes fiction, reads Oliver Sacks and spends time with her two cats and bird. Courtney is currently located in Minneapolis. For more information and other inquiries about this article, contact the author at email@example.com.