Some people find it hard to decide things. Now, researchers say they have found that the intensity of the communication between different regions of the brain dictates whether we’re indecisive. It’s the same old story: You’re in a restaurant and can’t make up your mind on what to order. After studying the menu for some time and many discussions, you eventually choose the steak. But you can’t relax during the meal and keep wondering whether you should have gone for the veal. Mach Principle has more:
Such difficulties crop up in all aspects of life. But they mainly affect preference-based decisions, questions like “what do I prefer—melon or cherries?” according to scientists. Purely sensory decisions, like “what is bigger—melon or cherry?” are less prone to indecisiveness. So how come some people are so uncertain while others know exactly what they like and want?
The researchers behind the study found that the key for stable preference choices is the intensity of communication between two brain areas that represent our preferences or are involved in spatial orientation and action planning. The investigators used a non-invasive brain stimulation method that leads to coordinated oscillations in the activity of specific brain regions. The test subjects, who didn’t know they were being stimulated, had to make preference-based or purely sensory decisions about food.
Using the technique, called transcranial alternating current stimulation, the researchers intensified or reduced the information flow between the prefrontal cortex, just behind the forehead, and the parietal cortex just above both ears.
“Preference-based decisions were less stable if the information flow between the two brain regions was disrupted. Our test subjects were therefore more indecisive. For the purely sensory decisions, however, there was no such effect,” said Christian Ruff, a neuroeconomist from the University of Zurich in Switzerland who led the study.
So “the communication between the two brain regions is only relevant if we have to decide whether we like something and not when we make decisions based on objective facts.” There was no evidence of any gender-specific effect, he added.