How Morals Are Reflected in the Brain

Why are some people more likely to perform community service, or give to charity, than other people? Why do some people seem to have clear moral judgment, while others are utterly lacking? A new study, published in Scientific Reports, delved into how brain functioning correlates to moral development.

The study was based on the theory of stages of moral development, developed by American psychologist Lawrence Kohlberg (1927 to 1987). Kolhberg had put forth a six-stage model, including preconventional morality, conventional morality and post-conventional morality. For example, stage one is the toddler-like stage, where a child simply does right or wrong, based on avoiding punishment. Moral maturation can escalate up to an enlightened stage six. According to GoodTherapy.org, this is defined as someone who is “focused on upholding principles of universal justice, fairness, and ethics. They believe in the democratic process, but also endorse disobeying unjust laws.”

For this study, researchers were using this moral stages concept, and checking to see if moral reasoning is connected to measurable brain function. They looked at 700 Wharton MBA students and tested moral reasoning. Individuals who had a high level of moral reasoning did have different brain activity than others. They showed increased brain activity in the area of the brain’s frontostriatial reward system, both while the subjects were at rest, and when they were performing decision-making.

“To our knowledge, this study is the first to demonstrate the modulation effect of moral reasoning level on human brain reward system activity,” wrote the study’s senior author, Hengyi Rao, Ph.D. “Findings from our study provide new insights into the potential neural basis and underlying psychological processing mechanism of individual differences in moral development.”

“Our study documents brain function differences associated with higher and lower levels of moral reasoning. It is still unclear whether the observed brain function differences are the cause or the result of differential levels of moral reasoning,” explained the co-author of the study, Diana Robertson, Phd., a professor of Legal Studies and Business Ethics at the Wharton School. The researchers believe that factors of nurture, such as parental involvement, schooling and life experience, and nature, such as biology, may all contribute to individual differences in moral development.

Future studies will look at whether education can promote moral reasoning past the time when brain maturation is complete.