The nervous tissue enveloped by three meningeal layers, The central canal also called ependymar canal, A grey matter on the inside consisting of horns, A white mater on the outside consisting of myelinated nerve fibres

Their apparent origin is the base of the encephalon (cranial nerves) and the spinal cord (spinal nerves), Spinal nerves and some of the cranial nerves contain both sensory fibres and motor fibres, Some cranial nerves contain fibres belonging to the vegetative nervous system (the vagus nerve), The spinal nerves innervate several structures such as the skin, skeletal muscles, joints, blood vessels, mucosae, sweat glands (with the exception of the head and the neck)

They represent most of the encephalon and control complex mental functions, The insular lobe or insula is a deep area of the cerebral hemispheres, Each hemisphere contains the frontal, parietal, temporal and occipital lobe, They represent the centre of reasoning and memory and greatly determine the intelligence of an individual

The frontal lobe is anterior to the central sulcus, The parietal lobe is posterior to the frontal lobe and separated from it by the central sulcus, Below the frontal lobe and separated from it by the lateral sulcus, lies the temporal lobe, Posterior to each hemisphere, lies the occipital lobe

It is situated in the frontal lobe, Contains large pyramidal neurons which generate impulses transmitted along the corticospinal tract, The frontal lobe, in Broca’s area, is responsible for the motor activity connected to speech and language processing, Due to the crossing over of the corticospinal tracts, the impulses received from the left hemisphere control the motor activity of the body’s right side