As scientists have been able to pinpoint a brain region in rats whose function is required to for the animals to express confidence in their decisions, a new study has revealed that confidence is a measurable quantity and not just reserved for humans.
According to the study by scientists at Cold Spring Harbor Laboratory (CSHL), rats are willing to 'gamble' with their time, which is something that can be measured and created on mathematical models to explain further, and the time rats are willing to wait predicts the likelihood of correct decisions and provides an objective measure tracking the feeling of confidence.
The team, led by CSHL Associate Professor Adam Kepecs hypothesized that a distinct region of the brain might control confidence. Previous work has suggested that the orbitofrontal cortex (OFC), a part of the brain involved in making predictions, might have a role in decision confidence. The team specifically shut off neurons in the OFC, inactivating it, and found that rats no longer exhibited appropriate levels of confidence in their decisions.
Kepecs said that with an inactive OFC, the rats retained the ability to make decisions - their accuracy did not change and they spent the same amount of time waiting for a reward on average. The only difference is that animals' willingness to wait for a reward was no longer guided by confidence. They would often wait a long time even when they were wrong.
The study was published in Neuron.