- A sub-region in the prefrontal cortex may explain why people don't practice what they preach
- Researchers used fMRI to study brain activity during tasks weighing honesty against profit
- The ventromedial prefrontal cortex (vmPFC) showed less activity in people displaying moral hypocrisy
A sub-region within the prefrontal cortex, which helps with higher-level functions such as goal-oriented behaviour and decision-making, could be responsible for why some people don't practice what they preach, according to a study.
Researchers explored the neural basis of moral inconsistency by scanning people's brains using functional magnetic resonance imaging (fMRI) during a task that required them to weigh honesty and profit.
"Moral consistency is an active biological process," co-author Xiaochu Zhang, of the University of Science and Technology of China and Guizhou Education University, said.
"Being a 'moral person' requires the brain to integrate moral knowledge into daily behaviour -- a process that can fail even in people who know the moral principle perfectly well," Zhang said.
The participants could earn more money by being dishonest, but were also asked to rate their own behaviour on a 10-point scale from "extremely immoral" to "extremely moral".
The researchers also monitored brain activity while the participants judged the morality of other people undertaking the same task.
Findings published in the journal Cell Reports revealed that among people who displayed hypocrisy -- behaving dishonestly despite judging the same behaviour as immoral in others -- the ventromedial prefrontal cortex (vmPFC) was less active and less connected to other brain regions involved in decision making and morality.
In people who were morally consistent, meaning that they judged themselves and others by the same moral standards, the vmPFC was activated similarly during both the behavioural and judgement tasks.
"... participants with higher moral inconsistency exhibited reduced judge score representation across tasks and weaker connectedness during the moral behaviour task in the ventromedial prefrontal cortex (vmPFC)," the authors wrote.
The team examined whether activity in the vmPFC caused moral inconsistency by stimulating the brain region among a fraction of the participants using a non-invasive method called transcranial temporal interference stimulation, before they engaged in the tasks.
Boosting activity in the ventromedial prefrontal cortex was seen to result in higher levels of moral inconsistency compared to participants who received mock stimulation.
The results suggested that morally inconsistent people don't make use of their vmPFC to integrate information when making behavioural decisions, the researchers said.
"As neuroscience researchers, we wanted to understand why knowing the right thing to do doesn't always translate into doing it," Zhang said.
"Individuals exhibiting moral inconsistency are not necessarily blind to their own moral principles; they are just biologically failing to consider and apply them in their own moral behaviour," the co-author said.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
