Experts announce the discovery of a previously-unidentified neural circuit, which may play a critical role in determining when the person we're talking to is lying or being honest. Malfunctions in this pathway may be underlying paranoia, some now believe.
This condition, in which some people become suspicious of each single action another those, and which also include jealous taken to extreme, still holds many mysteries for researcher teams.
But paranoia is also a debilitating mental disorder, that severely affects the quality of life in people suffering from its effects. Those around paranoid patients also have a hard time coping with the situation, because they are always placed under unfounded suspicion.
In order to be able to assist these individuals and those next to them, researchers at the University of Oxford in the United Kingdom set up a batch of experiments designed to tease out the neural pathway we use to determine other people's truthfulness.
Unlike most other species, we have something called “theory of mind,” which is a very wide concept that includes a variety of things, such as our ability to put ourselves in another's position.
We can determine how the person we are talking to is feeling, what they are thinking, and we can also accommodate their behaviors and values as our own. Other animals are incapable of doing this.
“"We're trying to find a specific circuit that performs social learning,” explains Oxford investigator Matthew Rushworth, who was a member of the team that carried out the new study .
Details of the conclusions were presented in London on December 2, at the Cell Press Lab Links conference, New Scientist
The researcher and his team used brain-imaging methods to keep an eye on the level of activity in volunteers' brains, while the participants were put in a situation where they had to choose between to boxes in order to win points.
Through a speaker, a second player gave each of the participants advices about which box to choose, but sometime he or she gave false advice. Whenever test subjects felt they were being lied to, something remarkable happened.
In an area located near the front of the brain, called the dorsomedial prefrontal cortex (DPFC), activity levels spiked significantly. This did not happen when the participants did not suspect they were being lied to, or when the second player was truthful.
Moreover, whenever the suspicions proved unfounded, activity in the DPFC decreased, “suggesting the volunteers needed to rethink their opinion of the second player,” Rushworth explains.
The expert adds that, as this system fails, various side-effects may appear. University College Longon expert Chris Frith, who did not participate in the study, believes that the new study explains why schizophrenia patients are oftentimes paranoid.
“People with schizophrenia show false prediction errors: they keep thinking their predictions are wrong,” he explains, and the main consequence of this are elevated levels of distrust and paranoia.