Cortex

The cerebral cortex is the brain's outer layer.

The cerebral cortex is made up of gray matter.

He says when a person makes an emotional or moral decision, it activates a part of the brain, just behind the eyes, called the medial pre-frontal cortex.

In the study, led by Ryota Kanai of the University College London, people who identified themselves as liberals generally had a larger anterior cingulate cortex — a comma-shaped region near the front of the brain that is involved in decision-making. By contrast, those who identified as conservatives had larger amygdalas — almond-shaped structures that are linked with emotional learning and the processing of fear.