My mom seems to be getting more confused with things such as determining if it is day or night, opening her medicine dispenser that has already been prepared for her, and turning her oxygen condenser on and off. So far, her doctors don't seem concerned about her mental status as she knows who she is, roughly when it is (season), and where she is. I know all of those things are important, but I also know something is seriously off with her. She does not have any kind of infection (they did check that when I had her at the doctor the other day).
But don't confuse social skills (or ability to have a polite conversation and chat) with rationale, like capnhardass said. My dad could sit and have a social conversation with someone, 'Hi, how are you?' type of thing but then put two shirts on a half an hour later.
You're noticing those little things and your mom is lucky that you do notice those things. You'll be on the lookout for things that might be a danger to your mom because of her dementia, even if it's in the early stages. We often don't realize that someone is a danger to themselves until they put themselves into a dangerous situation (leaving on the gas burners or wandering outside alone).
.Like OncehatedDIL said phone dialing, checkbook.. But then it's like on steroids...
I know now I have to keep reminders for myself to check on things my Mom should be doing..Now it's daily she asks me what pills she should take, she doesn't want to shower, if she naps she doesn't know if it's morning or night when she wakes...She gets confused about what season it is..Turns on the TV remote and looks at the phone answering machine to come on..
She doesn't have much interest in seeing anyone or family.. If she is in a social situation she can't follow the conversation and would rather sit alone in front of the TV..
But ask her about where she went to high school or her Mom & Dad, she'll remember all that...
You notice it's short term memory they have trouble with...
She could still use her old phone on the wall, her cell phone became impossible for her.
She couldn't remember whether or not she had taken her meds, so she took them again.
The biggest marker was her checkbook. Writing checks became more and more difficult, math became impossible. We could see how far back the dementia had started being a problem by looking through several years past checkbook registers.