Oscar Levant proclaimed, “Once I make up my mind, I’m full of indecision.” For most of us too, almost every time decision-making equals a debacle. When we make a choice, we may or may not be very confident about the decision we have made. Researchers at the Wellcome Trust Centre for Neuroimaging at UCL led by Professor Ray Dolan have identified how two areas of the brain are involved in the decision that is made and the confidence in that decision. This study sheds light on why some people have better insight into their choices than others.
We constantly have to evaluate our options and make decisions based on the information we have. The confidence we exude in those decisions obviously important. For example, investment bankers have to be sure that their choice is right when deciding where to put the money they are managing.
These researchers have located specific areas of the brain that swing into action to calculate both the value of the choices we have in front of us and our confidence in those choices, giving us the ability to know what we want.
The team used Functional Magnetic Resonance Imaging [fMRI] to capture activities in the brains of twenty hungry volunteers as they made choices between food items that they would later eat. To determine the subjective value of the food options, the participants were asked to indicate the amount they would be willing to pay for each snack. Then after making their choice, they were asked how confident were they that they had selected the best snack.
It has previously been shown that a region at the front of the brain, the ventromedial prefrontal cortex, is crucial for calculating the value of decision options. The new findings reveal that the level of activity in this area is also linked to the level of confidence in the choice of the best option. The study shows that the interaction between this area of the brain and an adjacent area reflects participants’ ability to access and report their level of confidence in their choices.
Dr Steve Fleming, a Sir Henry Wellcome Postdoctoral Fellow now based at New York University, explains: “We found that people’s confidence varied from decision to decision. While we knew where to look for signals of value computation, it was very interesting to also observe neural signals of confidence in the same brain region.”
Dr Benedetto De Martino, a Sir Henry Wellcome Postdoctoral Fellow at UCL, added: “Overall, we think our results provide an initial account both of how people make choices, and also their insight into the decision process.”