fMRI hints 'will' and 'grace' are not equally honest

Honest people tell the truth, even when given a chance to lie, as shown in an fMRI brain study of truth telling and prevarication from Harvard behavioral scientists.

The group, led by Joshua Greene, an assistant professor of psychology at Harvard, assessed 35 subjects who attempted to predict random coin flip outcomes while undergoing fMRI. Rewarded for accuracy and punished for inaccuracy, the study design also allowed them to cheat. Researchers found honest individuals displayed little to no additional neural activity in control-related brain regions when telling the truth, but liars did. Prevailing theories behind lie detection, “will” and “grace,” hypothesize that honesty results either from an active resistance to temptation or from a lack of response to it. Study findings lean toward the latter, according to researchers (Proc Natl Acad Sci USA 2009).