The anatomy of your brain reflects your introspective capacity, or ability to self-judge the merits of your decisions, new research indicates.

The study found that people with stronger reflective, or introspective, ability appear to have a higher volume of gray matter, the outer layer of the brain, in the part of their brains sitting behind their eyes. This region is called the anterior prefrontal cortex.

This discovery fits with previous work that showed people with damage to this brain region had trouble assessing their own decision-making, even though their performances on a task were unimpaired.

"In terms of looking at variation across a population of healthy individuals, our study is the first to say how [introspection] might link to structure," said study researcher Stephen Fleming, a neuroscientist at the Wellcome Trust Centre for Neuroimaging at University College London.

There was a second anatomical connection as well. Fleming and his colleagues also found a connection between introspective ability and the integrity of the white matter that connects with the anterior prefrontal cortex. In other words, better white matter was also linked with a greater ability to think about thinking. nullnullnullnullnullnullnull