Description

Most of the time we are not aware of the functioning of our memory. Although everybody sometimes forgets information, we only become aware of how vital our memory is really is when we are confronted with people with a memory disorder. A decrement in memory functioning is the primary symptom of dementia. Besides that, at least one of the following disorders must be present:

• a language disorder
• a disorder of doing simple tasks (such as putting clothes on)
• an inability of recognizing objects
• a disorder of organizing and planning

These disorders must be present because of psychological dysfunction. For example, if someone can not put his clothes on because his joints are inflexible this is not the case. And if someone can not recognize an object because his vision is bad, there is also not necessarily a psychological dysfunction.
Please notice from this description that dementia is not a disease itself. Dementia is nothing else than a number of symptoms that exist at the same time. Dementia can be caused by a disease, such as Alzheimer's disease.

Normal

When you are aging or your parents are and they forget things more than before, you might ask yourself the question 'When is a deterioration of memory functioning abnormal? This is not an easy question. Let's emphasize that some deterioration of memory with age is absolutely normal. It is normal even for young people to not know exactly which date it is or which day of the week it is. Normal becomes abnormal when the deterioration is so serious that it influences your daily life in a negative way. At a department of neuropsychology you can let yourself be tested to see if your memory is still functioning properly.

Abnormal

A number of causes for dementia are possible. These different types can differ in a number of ways.

• Alzheimer's disease. This is the most common cause of dementia. It is characterized by a slow onset and a progressive deterioration. The diagnosis of this disease can only be made after death when studying brain tissue under a microscope. The best diagnosis possible before death is 'probable Alzheimer's disease'.
• Parkinson's disease. People with Parkinson's disease not necessarily have dementia. Research points out that 30 percent of the Parkinson's disease patients have dementia. Parkinson's disease often co-exists with depression. The most important characteristics are: hypokinesia (for example difficulty in initiating movement), slowness of movement, tremor in the limbs, face or tongue, rigidity and gait disturbance.
• Cerebrovascular pathology. A cerebrovascular dementia usually begins very sudden. It is very important to recognize this type of dementia as vascular because unlike the Alzheimer type, this type of dementia can sometimes be treated very well. In other words, this type is possibly reversible. A neuropsychologist can play an important role in the diagnosis, in addition to a neurologist and a radiologist.
• A major depression can show symptoms that look like dementia and sometimes it is impossible to make the correct diagnosis. A neuropsychologist can use depression tests and observe the patient to see if there might be a depression present. Also, certain behavior during the testing can indicate depression. An example of this is the frequent occurrence of 'don't know' answers.