Quite a few comments over the past several months have mentioned the difficulties for caregivers when the person with dementia "refuses" to recognize his impairment.

Understandably, this can drive some caregivers absolutely crazy. The patient with considerable financial resources persists in disastrous judgments. The now-dangerous driver insists on driving. Important issues about the future can't be addressed. Both caregiver and patient get frustrated and angry.

The term for this lack of insight is "anosognosia," from the Greek words nosos, "disease" and gnosis, "knowledge" while the prefix a- changes it to a negative: "no knowledge of the disease." It's a condition in which a person suffering from neurological disability seems unaware of it.

From my medical training, I'm familiar with this condition when caused by a stroke: victims remain unaware of their affected side and will deny that they're hemiplegic. But it's also common in Alzheimer's.

Most caregivers understandably interpret this condition as psychological denial, but it's not. A blogger on the Alzheimer's Disease International website writes:

"Denial is a strategy used to reject something that a person wants to ignore or avoid because it is too difficult to face. Anosognosia, on the other hand, is being unaware of a decline in cognitive skills."

Research has shown that this condition is due to physical damage to specific areas of the brain. The patient has no more ability to recognize her symptoms than she does to lift her arm.

When Alzheimer's damages these areas of the brain, the patient simply cannot recognize her impairment.

The importance to the caregiver of understanding the cause of this lack of awareness is obvious. Trying to cajole or convince a person into recognizing his or her disability will fail, and will lead only to frustration and anger in both caregiver and patient.

Recognizing that the patient has no control over his denial, of course, won't change the practical problems, but it might help prevent the blaming and mistrust that so often results. Realizing that your loved one can't see that their mind is failing, and that no amount of reasoning or reminding is going to make any difference, might increase compassion and decrease frustration.

Although the problem may decrease as the Alzheimer's worsens, there is no known treatment. But, as the author of "Contented Dementia" suggests, in the context of other problems, trying to see the world from the perspective of the person with Alzheimer's will help.

How might it feel to have others harping on your incompetence when you know yourself to be unimpaired? What's it like to be unable to accomplish something important when you see no good reason why you can't?

Is it possible for you, the caregiver, to create an alliance with the patient to reduce his frustration? Can you find a way to "agree to disagree"? Can you feel less of a sense that you're betraying the person with Alzheimer's when you arrange for authorities to take his driver's license away (ideally without letting the patient know that you were responsible).

No amount of understanding, of course, is going to make it easy for you to respond to this condition, but it may make it possible to stay in a better relationship with the person you love.

Editor's Note: David's journey with Mild Cognitive Impairment was chronicled in "Fade to Blank: Life Inside Alzheimer's" an in-depth look at the real lives of families impacted by the Alzheimer's epidemic. His story continues on his personal blog on AgingCare.com.