Healthy brain. Coloured magnetic resonance imaging (MRI) scan through the head of a 55 year old man, showing the brain sectioned in coronal (frontal) view. Inside the skull the cerebrum of the brain (yellow) has many folds, divided into two hemispheres responsible for intelligent and conscious thought. Two ventricles (cavities, pink) are seen in the cerebrum. Beneath is the cerebellum (blue) which maintains posture, balance and co-ordinates movement. The skull surrounds and protects the brain and muscles (light blue) are seen in the neck. MRI scanning creates inssliceins images through the body using radio waves and a powerful magnetic field; it is used to determine the health of the brain.