Eli5 What is the differences between early dementia and normal forgetfulness?


Eli5 What is the differences between early dementia and normal forgetfulness?

In: 18

I’m not a doctor.

Forgetfulness is forgetting where you dropped your keys or leaving your lunch on the counter instead of taking it with you to work.

With dementia I think the distinction I’ve seen in family members is forgetfulness with confusion.

Edit: the movie Still Alice does a really great job showing the decline.

Forgetfulness: You’re about to go on a walk, and as you’re getting ready you move your water bottle from the kitchen table to the small table by the door. You grab a couple more things, and as you’re ready to leave you go back to the kitchen to grab your water bottle but can’t find it. After a little bit of searching you see it by the door and go “Oh yeah that’s right, I put it by the door, duh!”

Dementia: You do the same thing as before, but this time you go back to the kitchen and your water bottle that you clearly remember setting on the kitchen table isn’t there. After some searching you find it somehow moved to the table by the door. Obviously *you* didn’t move it, because that’s something you would have remembered, so that means *someone else* must have moved it, but you live alone so who could have done it? Someone must have broken into your house and moved it!

In the first example, you forgot you moved your water bottle, but after you saw it by the door you remembered moving it. This is completely normal. In the second example, you were confronted with the complete impossibility of your water bottle moving by itself, and since our brains are built to fill in the blanks, your brain rationalized it as the only thing it could think of: someone else must have done it, and then your brain worked backwards rationalizing it from there. This is a common symptom of dementia.

One of the differences is that healthy older brain works differently compared to a healthy younger brain – that would be forgetfulness – and the other is the result of some type of pathology

So as you get older it is true that you don’t have the same memory span for nonsense things, but you can still do the things that you did do in your field of expertise well. So a chess master is much better still than younger people at figuring out chess plays and remembering where chess pieces are on the board, but an older one of those is still worse than a younger person at memorizing random shapes and keeping them in short term memory

Processing speed is also not as good and neither are a lot of your senses, and you have to concentrate more on things like keeping your balance so the cognitive load is higher just for doing normal tasks. That means that you aren’t really paying attention to a lot of things also like where you put your keys so they never really get put into a short term memory which means you forget about them

Dementias are the results of some type of pathology. It can be things like Alzheimer’s disease or other frontotemporal dementia‘s. But there are also vascular dementia‘s and other types of pathology. These are really not the same as healthy aging.

You may start to lose the ability to really speak and understand words you may be suddenly just confused and disoriented, not just about special things and directions, but also why are you were even in a particular place. It becomes harder to plan out a series of tasks. Like for example in order to make food, you have to make a grocery list you have to get in the car you have to drive to the grocery store you have to do the shopping you have to pay for the shopping at the package shopping in the car – you get it. For many people with dementia it’s not just about forgetting where you parked, it’s about a complete in ability to plan and carry out that series of actions. That’s really different than forgetfulness

Another thing that people mostly forget about dementia is, is that they come with emotional and mood dysregulation

Most normal healthy aging, even that associated with forgetfulness or mild cognitive deficits, are not really associated with violence or social withdrawal or severe depression or mood swings or inability to regulate emotions or inability to suppress actions and make choices

So there physical differences is there are operational differences and there are emotional and social differences

I would also argue that there’s a lot of circadian differences, particularly in Alzheimer’s type dementias, but also in others, where there are sleep disruption and altered circadian rhythms of activity and hormones

One thing I noticed with my grandpa is that normal forgetfulness he would own up to. When he started to develop dementia he would hide that he didn’t know or remember things. He would make a mistake but then try to cover it up.