A recent neuroscience paper claims to determine whether your motives are selfish:

You may think a little white lie about a bad haircut is strictly for your friend’s benefit, but your brain activity says otherwise. Distinct activity patterns in the prefrontal cortex reveal when a white lie has selfish motives, according to new research published in Journal of Neuroscience.

White lies — formally called Pareto lies — can benefit both parties, but their true motives are encoded by the medial prefrontal cortex (MPFC). This brain region computes the value of different social behaviors, with some subregions focusing on internal motivations and others on external ones.

Kim and Kim predicted activity patterns in these subregions could elucidate the true motive behind white lies.

SfN, “Brain Activity Reveals When White Lies Are Selfish” at Neuroscience News The paper is closed access. (May 31, 2021)

Pareto lies?:

In the study, the team asked 43 participants to tell lies for three different purposes: to earn a reward for themselves (selfish lie), an unknown person (white/altruistic lie), or both (selfish white lie). They used functional magnetic resonance imaging (fMRI) to see what was happening in the MPFC and compare patterns of brain activity for each type of lie.

Different types of lies elicited activity in different parts of the sub-regions. For example, selfish white lies triggered greater activity in the underside and upper regions of the MPFC, while activity patterns in the underside was similar to that of selfish lies, and patterns in the upper sub-region were dissimilar to patterns observed for altruistic lies. Lauren Fuge, “Who benefits from a little white lie?” at Cosmos Magazine

Treat this one with big time caution. It relies on a small sample. And, apart from a universal judgement at the end of time, there is no such thing as “true motive.” There are only reasonable assumptions.

And always remember the dead salmon. The amazing discoveries neuroscientists made from the mind of a dead salmon.

There are many sources of reasonable assumptions and neuroscience is only one of them. It is certainly not a Big Tell.

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