Nervous System PDF

# The Central Nervous System - The human brain is composed of millions of neurons. - The cell bodies and synapses form the grey matter and the nerve fibres form the white matter. - The brain and spine are protected by bone and three meninges (membranes). - The space between the inner two meninges c...

# The Central Nervous System - The human brain is composed of millions of neurons. - The cell bodies and synapses form the grey matter and the nerve fibres form the white matter. - The brain and spine are protected by bone and three meninges (membranes). - The space between the inner two meninges contains cerebrospinal fluid, this acts as a shock absorber to protect the brain. - Meningitis is inflammation of the meninges: - Viral meningitis is more common and less severe, symptoms include headache, neck ache and fever. - Bacterial meningitis is more dangerous, symptoms as above but also skin rash, vomiting, intolerance of bright light etc. It is treated with antibiotics. # Structure of the brain - **Cerebrum** - largest part, consists of right and left cerebral hemispheres, controls voluntary movement, interprets impulses from sense organs, thinking, memory, emotions etc. The right hemisphere controls the left side of the body and vice versa. This is why a stroke in the brain may only paralyse one side of the body. The left hemisphere is for language, maths, analysis and logic. The right side specialises in art, music and emotional responses. - **Cerebellum** - second largest section. Controls muscular coordination and balance. The responses are involuntary. - **Medulla oblongata** - connects spinal cord with the rest of the brain, controls involuntary actions like breathing, swallowing, sneezing, and vomiting. - **Thalamus** - acts as a sorting centre for the brain. - **Hypothalamus** - regulates homeostasis, links with the pituitary. - **Pituitary** - not a part of the brain, produces hormones.