Which part of the brain is powerful enough to overwhelm individual thought and generate the desire to be part of a herd? Neuroscientists believe a neural network that includes the nucleus accumbens – more popularly known as the “pleasure centre” – is responsible. It is part of the limbic system associated with generating feelings and emotions such as fear, reward, punishment and pleasure.
Exposing subjects to situations that forced them to change their individual decisions to fall into line with those of a group, Basel university’s Vasily Klucharev and colleagues saw neural activity in the posterior medial frontal cortex – which monitors behaviour – and the nucleus accumbens using functional magnetic resonance imaging.
But when they temporarily shut down the cortices of the volunteers with a non-invasive procedure known as transcranial magnetic stimulation, the subjects ceased to adjust their behaviour to comply with that of the group. In other words, deactivating a specific part of the brain made subjects temporarily immune to social influence, and thus incapable of joining the herd mentality.