Orchid is a new reader to this blog and she posted a comment on the last posting, it was so interesting I thought I'd move part of her comment up here into the main section so it doesn't get missed!
Here is what she wrote:
First, Okaasan can't remember so many things, yet she remembers if the piles of laundry and garbage in her room are moved/altered. How is it that something so unremarkable can be remembered and she becomes angry? Surely the composition and height of the piles is something even people who don't suffer from dementia would not remember well. Also, she has been angry with you for long spans of time for cleaning her room, but how is it that she remembers what she is angry about for such a long period of time? Why does she remember her paranoid beliefs that you stole a magazine when she can't keep many other memories at hand for a minute?
Is dementia highly selective in this way? Is she storing new memories with an emotional component (those that make her angry or anxious) differently than those which have a neutral component? If so, can that be used to make sure she remembers things of importance which are positive?
I've studied neurobiology a tiny bit, and I know that memories are stored such that both the details and the emotions are locked in together. It is impossible for one to be elicited without the other, and ironically, when a memory is jogged by external stimuli, sometimes the details of the memory are not brought forth but the feeling is. This is why people have anxiety and don't know why in certain situations. The emotion stored with the memory of a similar experience comes out, but the memory itself doesn't make it. I don't know if this relates to dementia, but if your reading has revealed any answers about this selective memory situation, I'd be very curious to know.
1. I think she remembers what is important to her - and the "you stole my magazine" 2 years ago was a good example of that. Magazines are important to her. She makes special trips to the shops to buy the latest, she sits and looks at them in detail and copies down recipes from them. That time I probably removed a recently bought magazine...now I am much more careful and I take out magazines from the BOTTOM of the piles....!
I don't think she notices the changes in piles of clothes/newspapers/trash around her room - but if she can't find a particular item of clothing WHEN she is looking for it - then maybe the knowledge that we go into her room when she isn't there comes crashing to the fore.
She appears to remember the real angry times for about 5 days - or at least the emotion continues for about 5 days...and then it is gone again.
I reckon she DOES know we go in and remove clothes for washing and take out trash - but she accepts it basically.
2. Positive or Negative emotions, are they stored differently? I don't know! But I think the positive are easier to retrieve if SHE is basically happy in her days.
So every single time we eat okonomiyaki (savory pancake) it brings to life her happy memories of eating it after school as a child. I guess we ALL bury negative memories...
3. I think dementia sufferers do have selective memory - and for carers it can be disconcerting - you are never quite sure if she has remembered or not.
I've even seen her lose the memory of one of her own favorite stories...she is telling it as usual, and then the next piece of information isn't there. The following day - same story and the missing bit reappears! Once or twice I've supplied the forgotten details - but that confuses her because of course there is no reason why I should know HER story (except I've heard it a million times already).
It's all very strange....and interesting...funny...and frustrating....