One symptom of Alzheimer's can be hallucinations. I have never really had them, but I do hear things. The things I hear are not voices but "sounds that don't belong" -- like a door slamming when it shouldn't be or a car honking its horn when there are no cars around.
Quite frequently I hear a door in our house slam. I am usually in the back part of the house when I hear this and go out to see if my husband may have come in and I didn't hear his car pull up. But no, when I go look he is not home and there is no one hear but me and the cats. And, the door that I swear I hear slam is already shut and I knew it was all day long. I've mentioned this several times to my husband because it is so annoying but he always tells me not to worry about it -- it is probably a sound coming from the neighbor's house and it just sounds like it is coming for our house. So, I haven't mentioned it in awhile.
This weekend, our son was in Atlanta spending the night and expected to arrive home around noon on Sunday morning. At around 5:00 a.m. my husband "heard a door slam" and woke me up when I heard him say "Alan is home". When I looked at the clock, I knew there was no way Alan would be coming in at 5:00 a.m. when he was spending the night in Atlanta. I rolled over and tried to go back to sleep. My husband did not hear Alan come in or go to his room so he got up and went to look in the garage to see if the car was there. Alan was not home -- Ralph was "just hearing my noises"! I told him that it was the exact same sound I would hear during the day and how annoying it was. He was convinced someone had slammed that door. Now his explanation is "maybe we have ghosts"!