Mondays with Jean Vol II

K:  I know comparison is the thief of joy.  But,  when it comes to dementia v. Alzheimer's, what's the diff?

Last evening we hosted our weekly dinner with my mother-in-law.  We also welcomed home my son who recently graduated from law school and has returned to Dallas to work with my husband.  Upon his arrival my mother in law inquired if he was still in school and we explained that he had just graduated and her response was "I feel bad I didn't send a card".  We assured her she did but then for the rest of the evening the question arose about 15 more times on whether she sent a card.  She was always so current on birthdays. anniversaries and graduations with the hand  delivered or mailed card with $10 enclosed.  These are things SHE remembers at 91.  My parents don't have this ability to recall, let alone ask the same question twice in a day.  They have no idea my oldest graduated from law school.  They don't know to inquire what my kids are doing, granted not seeing them for long periods of time makes this more understandable.

So it begs the question.  Dementia v. Alzheimer's.  How can one brain slip so quickly and be categorized as one diagnosis, and another brain slowly slip into "dementia"?  I'm sure there are medical answers to this question, but in briefly discussing this with my sister this morning, she assured me our parents have it all.  And in a funny way, I thought, they really do!!