Is it common for people with complete dementia to have hours of clarity?

I look forward to reading lea’s article.
I have known of two cases. My DIL father had Parkinson and LBD. He had a couple of times where he was completely lucid. Much as you described. The family thought it was due to a new med but it did not last. This was in later days of his illness.
One day out of the blue my cousin called me on her way home from a Parkinson’s covention with her mom who is on hospice with Parkinson’s and dementia. Said she had exciting news and wanted to surprise me. I wasn’t home so she said that her mom had started talking again. Cousin said after her mom went on hospice she decided to try CBD oil to see if it would make a difference. I was very skeptical. I wanted to tell her about my DIL father because I didn’t think this would last but didn’t have the heart to do anything but encourage her to enjoy it. Her mom who has been nonverbal when I saw her in May had started talking in July within a week of starting the oil. She lost her Parkinson’s shuffle and flat expression. She made amazing improvements for over a year. Then she fell and lost a lot of ground. Stopped talking again. Had to have a hospital bed etc. Slowly she is improving again but not as dramatically as the first time. So, I know it does happen. The CBD oil appeared to be what was helping but the disease marches on. My cousin felt like it gave her mom back to her for a magical period of time. I would record her if I were you and you have the capability to enjoy in the future. Hugs to you and mom.

I have heard of episodes such as you describe which can happen in the hours, days and weeks before death. Check out this article which sheds light on the phenomenon:

https://www.scientificamerican.com/article/awakenings-in-advanced-dementia-patients-hint-at-untapped-brain-reserves/

Wishing you the best of luck with your mom. I hope you both continue to enjoy these periods of lucidity because it's a wonderful thing!

I have noticed that in the past with my LO when she was in the earlier stages. On some days, she might be rather chatty, recall events, act like herself......and I'd wonder if I had lost my mind. Was she really ill or had she recovered from dementia? But, it was momentary and the next day she's be back to the same dementia level. Just good days and bad days. Eventually, the good days stopped happening, though.

Yes, With Alzheimers and other forms of Dementia you can have moments of lucidity. They sometimes last for an entire day. They ocurred with my mother in the last years of her life. I certainly enjoyed them while they lasted. I made sure to have the Assited Living Community where she livedm call me to come when she was experiencing these episodes. It gave me small windows of time where we could interact -almost like in the past. It was joyful.

Yes, just recently. I too love those times with my LO.
Her diagnosis is Alzheimer’s, but I know that there are little idiosyncratic events in every case. I’m happy to have this be one of hers.

I have read an awful lot about dementia & alzheimers as I kneeded to educate myself since I cared for my Mother Who had Alzheimer's, and these times are referred to as moments of lucidity where by the Sufferer can engage perfectly in conversation and show a very improved alertness. Enjoy and allow the conversation flow as it may not happen that often.

I'm not saying that what you're talking about is this, but there is a condition called terminal lucidity that LO's & caretakers should be aware of: "Terminal lucidity, rally before death or end-of-life rally, refers to an unexpected return of mental clarity and memory, or suddenly regained consciousness that occurs in the time shortly before death in patients suffering from severe psychiatric or neurological disorders." (See Wikipedia)

I've also read that it's possible in cases of physical illnesses, where there seems to be a sudden and miraculous lucid recovery from a condition which had a grave prognosis (such as sepsis or coma), but shortly after the lucidity, the patient reverts and dies.

Of course! Anything from better blood perfusion to the brain, better eating so blood sugar is stable, better sleep the night before... can lead to these more lucid periods. Enjoy the times you can connect.

Yes, it is fairly common.

As another has mentioned, if she is close to the end, she could be having moments of terminal lucidity. Only time will tell.

Yes.