The brain is an extremely complex organ, consisting of several 'layers'. The layer which has evolved most recently and is most characteristic of higher primates such as ourselves is the cerebral cortex, the folded surface of the cerebral hemispheres, which has evolved most recently and is most characteristic of higher primates such as ourselves is the cerebral cortex, the folded surface of the cerebral hemispheres, which contains what is often referred to as grey matter. this is where the higher intellectual functions, including language, are located. There are various ways in which the cerebral cortex can be damaged. For instance, it may suffer injury from a blow to the head or through some other type of wound. Alternatively, it may suffer internal damage due to disease or a blockage in a blood vessel (an embolism or thrombosis), which results in disruption of the blood supply and the death of cortical cells. Areas of damage are generally referred to as lesions.