New research has shown that different patterns of activity in the prefrontal cortex reveal when a white lie has selfish motives, as published by its authors in JNeurosci, the journal of the American Neuroscience Society.
White lies can benefit both parties, but their real motives are encoded by the medial prefrontal cortex (CPFM). This region of the brain calculates the value of different social behaviors, with some subregions focused on internal motivations and others on external ones. The researchers predicted that the activity patterns of these subregions could elucidate the true motives for the white lies.
The team used a white lie stand, having participants tell lies to earn a reward for themselves, an unknown person, or both. They used functional magnetic resonance imaging to measure CPM activity of the participants and, by comparing the brain activity of the white lies with the selfish and altruistic lies, they were able to predict the true motivation of the lies.
Selfish white lies provoked increased activity in the ventral and rostral MFCS. Activity patterns in the ventral subregion were similar to those of selfish lies, while activity patterns in the rostral subregion they were different from the altruistic lies.