What is Parkinson’s disease?
Parkinson's disease is a progressive neurological condition caused by a decrease in the number of nerve cells in the part of the basal ganglia of the brain (the substantia nigra), which is responsible for the coordination of movement. These nerve cells are responsible for the production of dopamine, and so there is consequently a decrease in the amount of dopamine available to the body.
The symptoms of Parkinson's disease appear when the level of dopamine falls below 20% of normal levels, causing a lack of coordination and control of body movement that often appears as a tremor, stiff muscles and joints, and/or difficulty moving. It can also cause difficulty with speech. The dopamine levels continue to fall slowly over many years. People with Parkinson's disease tend to move slowly, shuffling their feet, finding it difficult to initiate movement, and developing a mask-like facial expression.
Parkinson's disease is most common in the elderly, with an occurrence rate of approximately 1 in 400 of the population over 65, and slightly more common in males than in females. It is caused by either atherosclerosis (hardening of the arteries) or unknown degenerative changes. When found in younger people, it is usually caused by poisoning or encephalitis (inflammation of the brain).
Reference : Human Disease - Crowley (Amazon link)
In this section we've added a few alternative study aids to help you along.
- Articles - Here you'll find a range of short articles on basic anatomy and physiology topics, complete with a few 'test yourself' questions for each one.
- Images and pdf's - Just in case you get tired of looking at the screen we've provided images and pdf files that you can print out and use for 'off-line' practice.
- Word Roots - When you learn the word roots, prefixes and suffixes contained within anatomical and medical terms, you can often work out what they mean. This can be a useful skill as you progress in your studies, so we've provided a dictionary to help you!
- Games - Finally in the resources section, we've added some simple games to make anatomy and physiology practice a little bit more fun.