Botox: long term side effects

There was a paper published recently, late last year, on an investigation of the effects of botox on CNS neurons using a 3D tissue culture model. See: https://pmc.ncbi.nlm.nih.gov/articles/PMC11022717/pdf/ADVS-11-2305326.pdf

I had a bad experience with Botox. I started treatment with it in late 2019, and by early 2021, I was complaining of symptoms that I describe as a form of dementia. One of several deficiencies that I noticed was that I was no longer able to do mental mathematical calculations and estimates which were customary and routine for me. I also experienced atypical (for me) mood disorders. This was a huge red flag, and I discontinued Botox treatments in early 2021. I have now (mid-2025) mostly recovered from the symptoms that were the subjects of my complaints. The initial onset of symptoms was subtle and delayed. It was at least 9 months into my treatment before I noticed any cognitive problems. Recovery was gradual with distressingly slow progress. I am now mostly recovered; I can do my customary mental math with little difficulty.
My suggestions for others: Do NOT use Botox *At ALL*, for *ANY* reason.