WHEN we fall under the spell of a charismatic figure, areas of the brain responsible for scepticism and vigilance become less active. That's the finding of a study which looked at people's response to prayers spoken by someone purportedly possessing divine healing powers.

To identify the brain processes underlying the influence of charismatic individuals, Uffe Schjødt of Aarhus University in Denmark and colleagues turned to Pentecostal Christians, who believe that some people have divinely inspired powers of healing, wisdom and prophecy.

Using functional magnetic resonance imaging (fMRI), Schjødt and his colleagues scanned the brains of 20 Pentecostalists and 20 non-believers while playing them recorded prayers. The volunteers were told that six of the prayers were read by a non-Christian, six by an ordinary Christian and six by a healer. In fact, all were read by ordinary Christians.

Only in the devout volunteers did the brain activity monitored by the researchers change in response to the prayers. Parts of the prefrontal and anterior cingulate cortices, which play key roles in vigilance and scepticism when judging the truth and importance of what people say, were deactivated when the subjects listened to a supposed healer. Activity diminished to a lesser extent when the speaker was supposedly a normal Christian (Social Cognitive and Affective Neuroscience, DOI: 10.1093/scan/nsq023).

Schjødt says that this explains why certain individuals can gain influence over others, and concludes that their ability to do so depends heavily on preconceived notions of their authority and trustworthiness.

It's not clear whether the results extend beyond religious leaders, but Schjødt speculates that brain regions may be deactivated in a similar way in response to doctors, parents and politicians.