"Mom!" the woman sitting in front of me in the airplane said to the older woman next to her. "You know you can't play those cards! They either have to be all the same number or all the same color!"

"Oh!" her mother said, sounding a little flustered. "That's right! I'm sorry!"

A few minutes later, the daughter - let's call her Ariel - repeated the same instructions. And again, her mother apologized and agreed. After three plays with the same results, Ariel decided to stop playing cards and got out magazines instead.

When her mother left the row to go to the lavatory, Ariel said to the third woman in the row, "Aunt Mary, I don't understand Mom's problem. She just won't do what she's supposed to. I told her again and again not to bring much cash, to get traveler's checks instead. What did she go ahead and do? She went to the bank and withdrew hundreds of dollars in cash!"

The litany went on. "She's just not keeping her act together! It's like she's not really trying. I explain and explain things and she goes and does something else. In the hotel last night I discovered that she didn't even bring the right clothes for this trip - after I told her and told her what the weather will be. And then she acts like I never told her anything."

Two days later and two thousand miles away, Virginia admitted, as she cleared out her mother's personal effects from her room in a nursing home, "It's better that she's dead. I used to get so ANGRY with her. She was an intelligent woman. But she kept saying and doing things that didn't make any sense. She knew better. I know she could have managed better if only she had tried harder."

Two states away, Suzanne was bewildered and hurt, reporting that her grandmother has lived with her and her family for 20 years, and continues to do so today - but after a brief hospital stay, did not recognize her room in her granddaughter's home.

Suzanne said, "We adore her, spoil her, wait on her hand and foot. But she is saying things like, 'I was a bother to you so you put me away,' things that are furthest from the truth." In fact, "Now we find her with the remote in her hand pleading to the TV, 'I need help, I need help, I have to get out of here.' This is very hard for all of us and we hate seeing her face looking so miserable."

A medical evaluation is important to check for reversible problems such as infections that can lead to confusion. That said, it is possible (and confirmed in some of the above cases) that the individuals were exhibiting early signs of dementia.

It may help to remember three points if you have relatives who act in a similar fashion.

First, they aren't behaving this way on purpose to annoy you. The impact of their actions on you is not a factor in their behavior. It's as if they constantly find themselves in unfamiliar territory without a map and without knowing the language spoken there. They try to make sense of the place and act accordingly - but they get it "wrong" much of the time, and don't remember what people tell them about the "right" way to behave.

Second, if they understand the gaps in their thinking and behavior, they probably find these lapses much, much more distressing than you do - although they may try to conceal this fact from you.

Third, if the changes in their behavior are early signs of irreversible dementia, that reality doesn't wipe out the meaning and value their lives have had for the previous seventy or eighty or ninety years. It doesn't erase their legacy - the impact of their lives on friends, family, the community, organizations for which they worked and so forth. It's easy to think, when a parent doesn't remember your name, that your whole relationship with them has been deleted. But it hasn't. Next week's column will talk about at least one way to help them - and others - remember and honor that legacy.