The brain is, quite literally, the nerve center of almost all we do. Information comes in, is processed, and instructions are sent out. Information enters along nerves connected to our eyes, ears, nose, tongue, skin, and insides. These information-gathering nerves — called sensory nerves — each have a tip especially designed to detect one kind of sensation.
Brain tumors are growths of abnormal tissue — either benign or malignant — in the brain. They may originate within the brain or spread from cancers elsewhere in the body.
As brain tumors grow, they cause increased pressure within the skull. Sufferers may have headaches and other symptoms such as double vision, weakness in the limbs, and memory loss. Outlook and treatment depend on where the tumor is and whether it is malignant.
Bell’s palsy is paralysis of the muscles of one side of the face. It is caused by pressure on the facial nerve which controls these muscles.
The face becomes asymmetrical, with drooping of the corner of the mouth, dribbling, and difficulty in closing the eye. It is a common condition and can occur at any age. Oral steroids may be used to reduce pressure on the nerve. Most sufferers make a full recovery.
Carpal tunnel syndrome
Carpal Tunnel Syndrome is a common cause of pain and numbness of the hand. It is caused by pressure on the median nerve, which provides sensation to the thumb, index, and middle fingers.
It usually affects middle-aged women, but also occurs in pregnancy and in sportspersons. Rest and splinting of the hand may solve the problem, but water tablets (diuretics), steroids, or surgery may be necessary.
Cerebral palsy (CP or spasticity), the most common crippling disease of childhood, affects one in 300 children. Children with CP cannot control their body movements because of brain damage which occurs around the time of birth.
It can be caused by infection, injury, or oxygen deprivation. When it is severe, children may have virtually no control over their movements. Less severely affected children may have weakness on one side of the body. IQ is not usually affected. There is no cure for CP, but physiotherapy helps to minimize disability.
Cervical spondylosis is caused by wear and tear on the discs between the vertebral bones of the neck. As the discs degenerate, arthritis develops.
The symptoms are pain and stiffness, tingling in the hands and arms (caused by pressure on nerves), dizziness, and headaches. Spondylosis is common and many people suffer without seeking medical help. An acute episode can be caused by twisting or lifting. Rest, painkillers, and a “collar” to support the neck usually allow the pain to settle down.
Dementia, a degenerative brain disorder, affects 10 percent of over-65s and 20 percent of over-80s. In the early stages the symptoms are forgetfulness, mood swings, and insomnia. As the disease progresses, there is intellectual impairment, memory loss, and disintegration of the personality.
Some 80 percent of cases of dementia are due to Alzheimer’s Disease in which the brain tissue shrinks and nerve fibers become distorted. Current research is examining genetic factors. Other possible causes of dementia are infection, alcohol abuse, and stroke. There is no cure for dementia.
Epilepsy is a condition in which the electrical activity of the brain is disturbed, resulting in convulsions (fits). It affects about one in 200 people and is more common in children.
The condition can run in families — if one parent has epilepsy there is a one-in-40 chance of a child being affected. An electroencephalograph (EEG) records the brain’s electrical activity and is used to diagnose epilepsy.
Epileptics have different types of fits. A grand mal fit causes loss of consciousness and an intense muscular spasm, followed by jerking of the limbs. Petit mal, a milder form of seizure, causes a brief period of loss of awareness during which the eyes stare blankly and concentration is interrupted.
Most epileptics are treated with anticonvulsant drugs that reduce or eliminate their fits.
Encephalitis, inflammation of the brain tissue, is caused by a viral or bacterial infection.
Very rarely it can develop after immunization. In its mildest form, encephalitis causes fever, headache, and listlessness; in severe cases, drowsiness and irritability, double vision, even coma.
Treatment, by drugs, depends on what is causing the inflammation. Encephalitis is most dangerous in the young and old and can be fatal.
Headache, probably the most common of all symptoms, is only rarely due to serious disease. Headaches are often caused by muscular tension in the neck, shoulder, and scalp. Poor posture and eyestrain also cause headaches. Rest and a mild pain killer are often all that is necessary for most headaches.
Migraine headaches — which are one-sided and accompanied by one or more symptoms of nausea, vomiting, and visual disturbances — often run in families and are more common in women than men.
They sometimes respond to simple painkillers, but other drugs, such as beta-blockers, are prescribed to prevent frequent attacks. Feverfew, a plant remedy, is an alternative preventive which is becoming popular. If headaches are persistent or accompanied by other symptoms, a doctor should be consulted.
A headache on awakening, together with nausea and vomiting can be a symptom of raised pressure within the skull. Headache together with eye pain may be a sign of glaucoma (raised pressure within the eye). Headaches with a fever and neck stiffness are symptoms of meningitis.
Hydrocephalus, water on the brain, is a condition in which there is a build-up of fluid around the brain. It can develop before birth and be diagnosed by an ultrasound scan during pregnancy.
If it is not treated, the increased pressure within the skull damages the brain and causes the head to enlarge. The excess fluid can be drained off to reduce pressure and protect the brain.
Meningitis is an infection of the membranes which surround the brain. It can be caused by both viruses and bacteria. Viral meningitis tends to be less serious than bacterial meningitis, which may be fatal if not treated.
The disease is most common in children and can cause deafness or other brain damage. Symptoms include headache, fever, vomiting, a stiff neck, and aversion to light.
Meningitis is diagnosed by a lumbar puncture, in which some cerebrospinal fluid is removed from around the spinal cord and tested for signs of infection. If bacteria are present, antibiotics are given.
Motor neurone disease
Motor neurone disease is a rare degenerative disease of the nerves which causes muscle weakness and paralysis. There is no treatment. Death is usually due to breathing difficulties. The cause of motor neurone disease is unknown, but it may be caused by a virus. The disease is rare under the age of 40 and affects about one in 100,000 people every year.
Multiple sclerosis (MS) is a chronic relapsing disease that destroys the coverings of the nerves in the central nervous system. It usually begins in early adult life and can affect almost any part of the body.
The most common symptoms arE muscle weakness affecting a limb, slurred speech, and visual disturbances. The attacks come and go, often affecting different parts of the body over many years. Severely affected people may develop paralysis and loss of bladder control.
Many sufferers remain mildly affected for many years. The cause of MS is unknown. Many treatments are available — steroids, high-pressure oxygen therapy, and special diets — but no one treatment is uniformly effective. MS affects one in 2000 people, is more common in women than men, and is rare in tropical countries.
Paraplegia, or paralysis of the legs and lower half of the body, is due to spinal cord damage from an accident, infection, or tumor. The symptoms are muscle weakness, loss of sensation, and impaired bladder and bowel control. There is no cure, but careful attention to potential problems such as urine infections and pressure sores helps prevent serious complications.
Parkinson’s disease affects one in 100 people over the age of 75. It causes a disabling tremor and stiffness which makes movement difficult.
It is caused by damage to a specific part of the brain where dopamine, a chemical messenger, is produced. As the disease progresses, it becomes more and more disabling, although the intellect is not normally affected. L-dopa, the most commonly used drug, is effective, but side effects often limit its usefulness.
Peripheral neuropathy is a disease of the nerves which provide sensation and muscle power to the arms and legs. The symptoms of peripheral neuropathy are weakness, numbness and sometimes pain, particularly in the hands and feet. Diabetes, which damages the nerves, is the most common cause of peripheral neuropathy.
Other causes include vitamin deficiencies (the B vitamins), cancer, and toxic drugs and chemicals. Damage to nerves can be limited if diabetes is well controlled and if vitamin deficiencies are corrected.
Strokes, the second most common cause of death in the US after heart disease, affect about one in 500 people every year. A stroke is caused by an interruption of the blood supply to part of the brain. There are two common causes: a blood vessel may become blocked by a clot, or a vessel may burst causing bleeding in the brain tissue.
The symptoms of a stroke depend on what pan of the brain is affected. Strokes on the left side of the brain often cause loss of speech and weakness on the right side of the body. When the right side of the brain is affected, the left side of the body is paralyzed. About a third of strokes are fatal; of those who survive, half recover completely and half are left with disabilities.
Risk factors for strokes include high blood pressure, smoking, diabetes, and raised cholesterol levels in the blood. Some doctors will prescribe aspirin to protect against stroke, particularly in patients who have already suffered one stroke.
Spina bifida is a defect of the vertebral column, present from birth, which leaves the spinal cord exposed. In the most severe cases there is paralysis of the legs. Hydrocephalus and mental retardation may be associated.
Spina bifida can be repaired surgically, but there is controversy over the ethics of keeping such severely handicapped children alive. The causes of spina bifida are not known, but mothers who have one affected child arc more likely to have a second.
Transient ischaemic attacks
Transient ischaemic attacks are mini-strokes lasting minutes or hours. They are most common in the over-60s and normally there is complete recovery within 24 hours.
The symptoms are similar to stroke symptoms — weakness in a part of the body, slurred speech, visual disturbances, and dizziness. They are due to a temporary blockage of a blood vessel in the brain which clears spontaneously. Treatment is aimed at preventing a full-blown stroke.