The Mayo Clinic notes that dementia is not a specific disorder but a term that encompasses a group of degenerative brain disorders where the patient had a loss of mental function; the most common form of dementia is Alzheimer's disease. When the patient develops severe dementia, she loses the ability to live without constant care. Many of the essential brain functions like memory, thinking and language are seriously damaged by dementia.
Understand Language
As dementia worsens, the patient has more problems with language. The National Institutes of Health (NIH) notes in the early stages of dementia the patient has trouble finding the right word. The patient's language abilities continue to decline, resulting in the patient being unable to pronounce words correctly; the patient will also verbally construct confusing sentences. Reading and writing are also affected in the middle stage of dementia. When the patient is diagnosed with severe dementia, he can no longer understand language. This means the patient will be unable to speak coherently or comprehend what someone else is saying to him.
Recognize Family Members
The NIH states that as dementia symptoms progress, the patient will no longer be able to recognize family members. This is a symptom of memory loss: it begins in the middle stage of dementia, where the patient forgets details about her life and who she is. At first, the patient may have difficulty remembering her spouse or caretaker, but in this stage the memory loss isn't permanent. When the patient develops severe dementia, however, the memory loss is full blown and the patient cannot recognize anyone who is close to her.
Perform Daily Activities
Another severe dementia symptom is when the patient can no longer perform daily activities. Starting in the early stages of dementia, the patient has difficulty performing regular activities, like balancing his checkbook. The NIH notes that when the patient reaches the middle stage of dementia, he has problems doing basic tasks like making dinner and choosing season-appropriate clothing. In severe dementia, the patient cannot live alone: he requires someone to help him use the bathroom, get him dressed and feed him.
