Changes In the Brain: 9 Types of Dementia
What Is Dementia?
Dementia is a term used to describe severe changes in the brain. When these changes occur, they cause memory loss. They also make it difficult for people to perform basic daily activities. In most people, dementia causes changes in behavior and personality.
Dementia affects three parts of the brain: the areas for language, memory and decision-making.
Most cases of dementia are caused by disease and cannot be reversed. Alcohol and drug abuse can sometimes cause dementia. In those cases, sometimes it’s possible to reverse the damage in the brain. According to the Cleveland Clinic, less than 20 percent of cases of dementia can be reversed.
Alzheimer’s disease is the most common type of dementia. Between 60 and 80 percent of cases of dementia are caused by this disease, according to the Alzheimer’s Association. Early signs of Alzheimer’s disease include depression and forgetting names and recent events.
Alzheimer’s causes brain cells to die. As the chemistry of the brain changes, patients experience confusion and mood changes. They also have trouble speaking and walking.
Elderly people are more likely to develop Alzheimer’s. Only five percent of cases of Alzheimer’s occur in people in their 40s or 50s. This is known as early onset Alzheimer's.
The second most common type of dementia is Vascular dementia. It’s caused by lack of blood flow to the brain. Vascular dementia can happen as you age or after a stroke. People with advanced heart disease are also at risk for vascular dementia.
The symptoms of vascular dementia can appear slowly or suddenly, depending on what’s causing the disease. Confusion and disorientation are common early signs. Later on, patients also have trouble completing tasks or concentrating for long periods of time.
Vascular dementia also causes vision problems and sometimes hallucinations.
Dementia with Lewy Bodies
Lewy Body dementia is caused by protein deposits in nerve cells. This interrupts chemical messages in the brain and causes memory loss and disorientation.
People with this type of dementia also experience visual hallucinations and have problems with sleep. Sometimes they have trouble falling asleep at night yet fall asleep unexpectedly during the day. They might also faint or become lost or disoriented.
Dementia with Lewy Bodies also shares many symptoms with Parkinson’s disease and Alzheimer’s. For example, many patients develop trembling in their hands, have trouble walking, and feel weak.
People with advanced Parkinson’s disease often develop dementia. The earlier signs of this type of dementia are problems with reasoning and judgment. For example, a person with Parkinson’s disease dementia might have trouble understanding visual information or remembering how to do simple daily tasks. Or they might have confusing or frightening hallucinations.
This type of dementia also causes a person to be irritable. Many patients become depressed or paranoid as the disease progresses. Others have trouble speaking and might forget words or get lost during a conversation.
Fronto-temporal dementia is a name used to describe several types of dementia. They all have one thing in common: they affect the front and side parts of the brain. These are the areas that control language and behavior.
Fronto-temporal dementia affects people as young as 45 years old. Although scientists don’t know what causes it, it does run in families. According to the Alzheimer’s Society, many people who develop this type of dementia carry a mutation in genes GRN, MAPT or C9ORF72.
This dementia causes loss of inhibitions and motivation, as well as compulsive behavior. It also causes people to have problems with speech, including forgetting the meaning of common words.
Creutzfeldt-Jakob disease (CJD) is one of the rarest forms of dementia. Only one in one million people are diagnosed with it every year, according to the Alzheimer’s Association. CJD progresses very quickly, and people often die within a year of diagnosis.
Symptoms of CJD are very similar to other forms of dementia. Some people experience agitation, while others suffer from depression. Confusion, loss of memory, and agitation are also common. CJD also affects the body, causing twitching and muscle stiffness.
Korsakoff Syndrome is technically not a form of dementia. However, because the symptoms are so similar, it is usually classified along with other forms of dementia. Korsakoff syndrome is caused by a serious deficiency of vitamin B1. Although it can be a result of malnutrition or chronic infections, the most common cause for this vitamin deficiency is alcoholism.
People who suffer from this disorder have trouble processing information, learning new skills, and remembering things. Sometimes people with Korsakoff Syndrome make up information to fill in the gaps in their memories without realizing they are doing that.
Mixed dementia refers to a condition in which a person has more than one type of dementia. The most common combination is vascular dementia and Alzheimer’s. Mixed dementia is very common. According to the Jersey Alzheimer’s Association, up to 45 percent of patients with dementia have mixed dementia but don’t know it.
Mixed dementia can cause different symptoms in different people. Some people experience memory loss and disorientation first, while others have behavior and mood changes. Most people with mixed dementia will have difficulty speaking and walking as the disease progresses.
Other Causes of Dementia
Many diseases can cause dementia in the late stages. For example, people with multiple sclerosis can develop dementia. It’s also possible for people with HIV to develop cognitive impairment and dementia, especially if they’re not taking antivirals.
Normal pressure hydrocephalus is a condition caused by fluid accumulating in the brain. The pressure of the fluid leads to a number of health problems, including dementia. This is one of the types of dementia that can sometimes be cured with surgery.
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