There are several diseases and disorders that may affect the brain. Some of these include:
Disorders leading to unconsciousness or altered consciousness
Coma is defined as a state where the brain is no longer alert and the body does not respond to inner or external stimuli. Common causes of coma include brain injury, thrombosis, embolism, brain tumor, metabolic disease, nutritional deficiency, poisoning and brain infection caused by falciparum malaria, tuberculosis, or syphilis, for example. In some cases, loss of consciousness may be only partial and this is termed altered consciousness.
This is caused by abnormal electrical activity in the brain.
Interruption of the blood supply to the brain can lead to paralysis and other complications. The risk factors for stroke include high blood pressure, diabetes, obesity, high blood cholesterol, smoking, excessive alcohol abuse, previous stroke, use of birth control pills and genetic predisposition.
Infections of the brain may affect the brain or the meninges. The brain is more prone to infection compared to other organs of the body such as the heart. Infections may be viral, bacterial or fungal.
Multiple sclerosis describes a condition where the protective myelin coating surrounding nerve fibres is damaged in the brain and spine causing problems with muscle movement, vision and balance.
Migraine, headaches and vertigo
Headache is a common symptom but may signify a deeper pathology in some individuals. Migraine is a common affliction affecting a substantial number of people worldwide.
This is a severe disorder of the nervous system that affects two in every thousand children. The condition leads to loss of control over muscles and movement, leading to severe disability.
Some other diseases and disorders that may affect the brain include:
Brain trauma or concussion caused by head injury
Hormonal or metabolic encephalopathies
Congenital brain disorders
Movement disorders and disorders of balance such as chorea, dystonia, tics, and tremors
Degenerative diseases such as dementia, Parkinson's and Alzheimer's disease
Myelopathy and motorneurone diseases
Reviewed by Sally Robertson, BSc