Scientists have pinpointed what in the brain makes some people more wishy-washy than others.
The study, published in the journal Nature Neuroscience, shows that levels of activity in a brain region, the ventromedial prefrontal cortex, correlate with our levels of confidence and decisiveness.
"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," study researcher Dr. Steve Fleming, a postdoctoral fellow at the Wellcome Trust Centre for Neuroimaging, who is now based at New York University, said in a statement.
The study included 20 study participants who were hungry and who underwent fMRI brain imaging as they decided what kind of food they wanted to eat among a variety of pre-set options.
The participants were asked to say how much money they would spend to have each food option (so that researchers could see how much they thought each option was worth), and then to pick the snack that they wanted to have.
After choosing their snack, the researchers had the study participants rate their level of confidence in having chosen the best snack.
Researchers found an association between activity in the ventromedial prefrontal cortex and the study participants' confidence levels when asked if they picked the best snack.
Another thing at play in decisiveness? Sleep.
A 2009 study in the journal SLEEP showed that when we don't get enough Zzzs, our ability to complete "information integration" -- being able to make a quick, accurate, snap decisions -- is impaired, ABC News reported.