A new study suggests a part of the brain called the lateral orbitofrontal cortex (LOFC) helps us make choices when we have to combine different sources of data, such when we vote.
In addition, researchers report that damage to the LOFC leads people to base decisions on simple information, such as a political candidate’s appearance.
Healthy individuals and those with brain damage affecting other parts of the frontal lobes spontaneously weigh both attractiveness and a candidate’s competence when casting a vote.
“How multiple attributes are combined in decision-making and how values are constructed is an important field that is just starting to be considered,” says Lesley Fellows, a neurologist and researcher at the Montreal Neurological Institute at McGill University and senior author of the paper in the Journal of Neuroscience.
“Recent research suggests that several areas in the brain carry information about the value of decision options, but it is not yet clear how these areas work together when we make a choice. The LOFC appears to be important when decisions are hard, helping to select the best from among options of similar value.”
The new study tested subjects with and without damage affecting the LOFC.
Participants took part in a simulated election, where they were asked to vote for real-life but unknown politicians based only on their photographs. They were also asked to rate the candidates’ perceived attractiveness and competence.
Participants without lesions in the LOFC appeared to make voting decisions based on both perceived attractiveness and perceived competence.
Although subjects with LOFC damage could rate the competence of the candidates, they didn’t use that information when voting—and relied only on attractiveness instead.
“This study provides a strong test of the function of this part of the brain,” Fellows says. “It shows that damage disrupts a specific aspect of how a decision is made. It provides evidence that LOFC is necessary for this function.
“This is the first time the brain basis of political behavior has been studied with these methods.”
The Quebec Fund for Research, Society, and Culture and the Canadian Institutes of Health Research funded the work.
Source: McGill University