Cerebral cortex

The cerebral cortex represents the outermost tissue layers within the forebrain (aka as cerebrum) of vertebrates. Together with the basal ganglia and the olfactory bulb, it forms the gray matter of the brain which contains large numbers of nerve cell bodies and is connected by white matter, characterized by myelinated nerve fibres. In reptiles and mammals, the cortex is folded into gyri and sulci which increases the surface area relative to the volume — a process known as gyrification. The thickness of the cerebral cortex varies between different regions, with values from around 2mm to 4mm. Changes in cortical thickness correlate with both brain maturation and aging and are especially pronounced in dementia.