When we humans are children, we probably want to try to experience everything, everything is new, we are learning all the time after our brains stop growing. Take a look at a young child, they will put everything in their mouth; eventually the word 'no' is attached with this behavior, and the behavior stops. That to me is called basic learning, if you're told 'no' often enough, or if you are spanked when you do something that your parents don't want you to do, you eventually get it. But all these 'events' are a function of a learning, experiencing, being...one eventually learns how to go to the bathroom, how to use utensils for eating, what the rules of school are, how to look both ways before crossing the street so you don't get hit by a car; they're all things that we learn to mold our behaviors into appropriate ways to act for the environment we are in.
Look at children in a church, for example; you'll see the behaviors of younger ones and their older siblings and they are different, the older ones have learned that appropriate behavior is to be quiet, move according to cues, etc. This to me means that the child has learned how to suppress reactions to certain stimuli, you still have the stimuli, you just learn how to deal with it, and eventually it becomes second nature; your brain 'filters out' some of the stimuli, and use the other stimuli to do something appropriate.
Its like toilet training perhaps, young humans just let things go and flow, we have diapers for that. Eventually older people 'train' children in the 'ways' of toileting, and it can be complicated, sense the urge, get to toilet, take off appropriate clothing, accomplish toileting and cleaning, put clothes back, wash hands, this kind of stuff.
Dementia, as I see it with Mom, is a condition known by problems with ordering and sequencing, and I think this can be evidence of the breakdown of the 'learning connections', the connections that we learn over time about how to 'accomplish' tasks. I've noticed it with Mom and toileting, most of the time she will understand the 'urge' to toilet, but then things break down, she'll not understand that clothes have to come off to make toileting happen, she won't understand or respond correctly to the 'its all done' feeling, and then she won't accomplish the the cleaning and reclothing part of the task correctly.
I'm sure that this can explain a lot of Mom's other behaviors, there's too much 'unfiltered' stimulation coming in for Mom to understand; this morning at Mass she was really confused, she knew that there were prayer books and song books in the pew ahead of her, but didn't know what to do with them except take them out of the little holder, put them in the pew, and then put them back (just like I've seen with very young children). When she couldn't figure out what the books said, she pointed at the cover of one and read her name in it.
At Communion time, Mom turned to me and said 'do we get one of those things too?', the contextual subleties of Communion and church are now lost on her.
I've got a window open over here, one can hear cars from the highway, but the drapes are closed. Mom heard the cars, went to where the noise was coming from, the window, peered through the drape, then turned to me and asked 'what's this?'. Again, a pretty simple thing for many of us to understand, cars make noise, open window lets in noise.
Things that we take for granted, like a shower, I can see become too much stimulation for dementia people, there's a temperature difference with the tile on the shower floor, you've got your clothes off, there's sounds, there's running water, big temperature swings, running water on a body; those of us with 'full minds' know the stimulation to expect and filter out the the other things that are not important for us to understand during a shower. We also understand the ordering and sequencing of what we do in the shower, its a very complicated place and procedure.
For a little 'self-test', try to do a flow-chart of 'going to the bathroom' for yourself, and then look at what could happen if you get one of the actions just a little bit out of sequence. Like if you forgot to wipe when you're finished, you're looking at a mess, or if you don't remember to get the toilet paper and try to use something else, like your hands, then what happens?
There are times I'm sure that Mom has filtering problems resulting in too much stimulation, and there are other times when I think that Mom just gives up, and filters everything out. Those are the blank times!
Autistic and Asperberger's people have similar 'problems' with filtering stimulation and ordering and reacting, I'm still learning about these 'brain' conditions.
I'd love to see some reactions to my little words from those in the early phases of dementia, as well as people who are caring for elders with dementia.