When you realize you are forgetting or misspelling a word, you may start to worry. Dementia is often confused with normal mistakes or depression and is not a part of normal aging.
Those who are depressed may have trouble concentrating, may be very negative, and overstate their problems. They may have memory lapses yet know who and where they are, and what they’re doing. Those who are depressed know what things are called and how to talk about them.
Those with dementia have a progressive loss of being able to think. They may call a pencil a “tree” and not know how to use it. They have trouble learning new information -- like the day, time, or where they are.
If you worry about changes in yourself or a loved one talk to a medical professional. Now is the time to make the most of your life.
References:
http://www.ehow.com/about_5366009_depression-vs-dementia-elderly.html
http://www.health.com/health/condition-article/0,,20188947,00.html