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Symptoms
There are 400`000 nerve cells in the nigra. They begin to pigment
after birth and are fully pigmented at age 18. The nigral pigment
differs from skin pigment.
This autoradiogram
shows a normal brain (left) and a brain afflicted with Parkinson's
disease. The substantia nigra cells (marked sn) are absent in the
brain with Parkinson's. The substantia nigra (trans. "black
substance") is an area of the brain rich in dopaminergic neurons
(neurons that make the neurotransmitter dopamine) and the black
pigment neuromelanin (hence its name). Loss of neurons from this
region in the Parkinson's disease brain leads to a dopamine deficit.
The symptoms of
Parkinsons disease become apparent after approximately 240,000
nerve cells, 60 percent of the total, die. In normal, unaffected
people, approximately 2,400 nigral cells die each year. Thus, if an
unaffected person lives 100 years he will, probably, develop
Parkinsons disease. In this disease, the nigral cell loss is
accelerated - more than 2,400 nerve cells die each year. It is
unknown why nerve cells loss accelerates- whether it is a genetic
(inherited) factor, an environmental (external) toxin, or a genetic
factor and an environmental toxin. It is also unknown when the nerve
cell loss accelerates.
The Symptoms of
Parkinson's Disease:
Tremors
Symptoms often start
with an occasional tremor in one finger that spreads over time to
involve the whole arm. The tremor is often rhythmic -- 4 to 5 cycles
per second -- and frequently causes an action of the thumb and
fingers known as the pill-rolling tremor. Tremor is present when the
limb is at rest or held up in a stiff unsupported position and
usually disappears briefly during movement. Tremors can also occur
in the head, lips, tongue, and feet, although they do not occur
during sleep. In one study, 44% of patients reported experiencing
internal tremors lasting less than half an hour, but occurring
several times a week. Symptoms can occur on one or both sides of the
body.
Motion and Motor
Impairment
Slowness of motion (bradykinesia)
is one of the classic symptoms of Parkinson's disease. Patients may
eventually develop a stooped posture and a slow, shuffling walk. The
gait can be erratic and unsteady and cause a person to fall. After a
number of years, muscles may freeze up or stall, usually when a
patient is making a turn or passing through narrow spaces, such as a
doorway. Intestinal motility -- e.g., swallowing, digestion, and
elimination -- may also slow down, causing eating problems and
constipation. The muscle rigidity (akinesia) experienced in
Parkinson's disease often begins in the legs and neck. Muscle
rigidity in the face can produce a mask-like, staring appearance.
Hand deformities may develop in late stages, causing severe
discomfort and limitation. Handwriting, for instance, often becomes
diminutive. Normally spontaneous muscle movements, such as blinking,
may need to be done consciously.
Speech Impairment
About half of
Parkinson's patients develop some speech difficulty caused by
rigidity of the facial muscles, loss of motor control, and impaired
breath control. Tone can become monotonous, words may be repeated
over and over, or the rate of speech may even be very fast.
Swallowing may be difficult.
Depression and Mental
Problems
Depression is often
present as one of the first symptoms and is probably partially
caused by a chemical imbalance in the brain. Because depression is
common in old age or can be caused by other factors, the patient
often does not connect it with other early symptoms of Parkinson's.
Defects in thinking, memory, language, and problem solving skills
often occur later on. Dementia occurs in almost 30% of Parkinson's
patients, who are usually older individuals who have had major
depression.
Other Symptoms of
Parkinson's Disease
The sense of smell is
impaired in about 70% of patients. Vision is also effected,
including color perception. The patient may experience changes in
sensations of temperature, hot flashes, excessive sweating, and
cramps and burning in the legs. Parkinson symptoms that may occur
after encephalitis include greasy skin and hair, tics, spasms, rapid
and repetitive speech, and oculogyric crises -- disturbances in
which the eyes become fixed in one direction for minutes or even
hours. In people with a history of migraine, the onset of
Parkinson's is associated with change in migraine symptoms (most
often improvement). Constipation is a major problem for Parkinson
patients and occurs both as a result of the disease and a side
effect of its treatment. Bladder control and urinary incontinence
are also problems, which can be improved or even eliminated by
training intensively on the GIGER MD medical device.
Impact on Emotions and
Mental Status
The emotional and
psychiatric impacts of the symptoms are devastating. Depression is
extremely common, although one study found that only about 7% of
patients met the criteria for major depression. Such patients were
generally much older and already had mental or psychiatric problems.
Depression in the remaining population was generally mild and most
likely due to the emotional effect of the disease on the lives of
both patients and their families -- not actual physical changes in
the brain. Dementia is about six times more common in the elderly
Parkinson patient than in the average older adult. Nearly all drug
treatments used for Parkinson's disease have side effects that cause
neurologic and psychiatric disturbances. The physical and emotional
impact on the family should not be underestimated as the patient
becomes increasingly dependent on their support.
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