A UCLA study suggests that scientists can help predict how people will react to moral dilemmas based on the brain’s response when they watch someone experience pain. Researchers analyzed mirror neurons, brain cells that respond equally when someone performs an action or simply watches someone else perform the same action. Mirror neurons play a vital role in how people learn through mimicry and feel empathy for others. When you wince while seeing someone experience pain — a phenomenon called “neural resonance” — mirror neurons are responsible.
“The findings give us a glimpse into what is the nature of morality,” says Marco Iacoboni, MD, PhD, director of the Neuromodulation Lab at UCLA’s Ahmanson-Lovelace Brain Mapping Center. “This is a foundational question to understand ourselves and to understand how the brain shapes our own nature.”
Dr. Iacoboni wondered if neural resonance might play a role in how people navigate complicated problems that require both conscious deliberation and consideration of another’s feelings. To find out, researchers showed 19 volunteers two videos: one of a hypodermic needle piercing a hand and another of a hand being gently touched by a cotton swab. During both, the scientists used a functional MRI machine to measure activity in the brains of the volunteers.
Researchers later asked the participants how they would behave in a variety of moral dilemmas, including silencing a crying baby during wartime to prevent drawing the attention of enemy soldiers, torturing another person to prevent a bomb from killing several other people and whether or not to harm research animals in order to cure AIDS. Participants also responded to scenarios in which causing harm would make the world worse — inflicting harm on another person in order to avoid two weeks of hard labor, for example — to gauge their willingness to cause harm for moral reasons and for less-noble motives.
Dr. Iacoboni and his colleagues hypothesized that people who had greater neural resonance than the other participants while watching the hand-piercing video also would be less likely to choose to silence the baby in the hypothetical dilemma, and that proved to be true. Indeed, people with stronger activity in the inferior frontal cortex, a part of the brain essential for empathy and imitation, were less willing to cause direct harm, such as silencing the baby. But the researchers found no correlation between people’s brain activity and their willingness to hypothetically harm one person in the interest of the greater good — such as silencing the baby to save more lives. Those decisions are thought to stem from more cognitive, deliberative processes.
The study confirms that genuine concern for others’ pain plays a causal role in moral dilemma judgments, Dr. Iacoboni says. In other words, a person’s refusal to silence the baby is due to concern for the baby, not just the person’s own discomfort in taking that action. Dr. Iacoboni’s next project will explore whether or not a person’s decision-making in moral dilemmas can be influenced by decreasing or enhancing activity in the areas of the brain that were targeted in the current study. The research could point to a way to help people with mental disorders such as schizophrenia that make interpersonal communication difficult.
“Deontological Dilemma Response Tendencies and Sensorimotor Representations of Harm to Others,” Frontiers in Integrative Neuroscience, December 12, 2017