The most basic fabric of civilization was woven on the principles of moral judgement, that is to say serving the interests of the community and others, instead of merely following self-interest at large. This is why some believe, arguably or not, that religion was a key civilizing factor since it laid out a moral workbook. Thou shall not kill, thou shall not steal, etc. Is there a certain brain mechanism where moral judgments are predominant? If so, does damage to certain brain structures impair moral judgement? A study at University of Iowa suggests so.

Their findings suggest that the brain’s ventromedial prefrontal cortex (vmPFC) is critical for the acquisition and maturation of moral competency—going beyond self-interest to consider the welfare of others.

“By understanding how dysfunction in the prefrontal cortex early in life disrupts moral development, we hope to inform efforts to treat and prevent antisocial behavior, from common criminality to the mass murders our society has witnessed in recent years,” says co-first author Bradley Taber-Thomas, postdoctoral fellow in psychology at Penn State University who earned his doctorate in neuroscience at the UI in 2011.
“It’s imperative that we find ways to promote the development of social-emotional brain systems to encourage healthy, adaptive social development from an early age.”

The moral brain

The scientists at UI recruited patients from the Iowa Neurological Patient Registry who had suffered damage to the vmPFC at age 16 years or younger. For control purposes, another group was recruited that early in life also suffered brain damage, but outside the vmpPFC, which did not intrude on other known emotion-processing structures like teh amygdala or insula.

Damage to the vmPFC shows up as black areas in two patients’ brain scans. In both patients, the damage occurred prior to age 18. Images courtesy of the UI Department of Neurology.

The recruits were faced with 50 hypothetical scenarios of various conflicting nature and asked to answer “yes” or “no”. In high-conflict scenarios, the options present competing social-emotional (personal) and utilitarian considerations (e.g., smothering a crying baby to save a group of people). In low-conflict scenarios, at least one of those conflicting considerations is absent.

The low-conflict scenarios were at their own hand divided into two key branches: those that were mainly self-serving and those that were utilitarian to society. Self-serving scenarios (e.g., harming an annoying boss) probe the integrity of moral development by pitting a self-serving action against a moral rule. Utilitarian scenarios (e.g., lying to save others from physical harm) pit a utilitarian principle against impersonal harm.

The researchers found that those who suffered a vmPFC injury were significantly more likely to endorse the low-conflict self-serving action than all other groups. For nonmoral and low-conflict utilitarian scenarios, there were no significant differences between the D-vmPFC group and all other groups. Additionally, the the earlier in life the vmPFC damage occurred the higher the likelihood of endorsing low-conflict self-serving actions.

“This shows that vmPFC dysfunction does not disrupt all types of judgments, or even moral judgment in general,” Taber-Thomas says. “The disruption is specific to circumstances where self-interest is pitted against the welfare of others.”

What this suggests is that maybe the vmPFC is critical for children to grasp that self-serving actions are aversive based on early life experiences.

“Patients with adult-onset vmPFC damage functioned normally, while early-onset patients have a much higher rate of endorsement of these self-serving behaviors,” Tranel says. “Is it okay to cheat on your taxes? The patients who sustained damage to the vmPFC early in life chose this option. This parallels what shows up in patients with psychopathy.”

By all means cheating on your taxes doesn’t make you a psychopath, but what’s interesting to takeaway is that people don’t always make the correct decisions about right and wrong, and this all my be due to how your brain is hardwired, instead of an underlying psychological principle. How long before research like this appears in court, defending people accused of laundering money. “I can’t help it, i hit my head when I was a little kid, so you see… my moral judgement is impaird”. That would be interesting.

The findings were reported in a paper published in the journal Brain.