I think I may have FND. I have these jerks and subtle lurches that would not fall under PD (and I have not been diagnosed with PD). I have been diagnosed with REM Sleep Behavior Disorder, which is likely a sign of something not good coming, but I am working on heading that not good thing off at the pass.
From what I can find, FND is not degenerative and some people recover: Functional neurological disorders: acute presentations and management ncbi.nlm.nih.gov/pmc/articl...
Also, I had read about 8 months ago that intranasal Oxytocin helps with symptoms of FND: The Effect of Intranasal Oxytocin in Patients With Functional Motor Symptoms: A Preliminary Open-Label Case Series sci-hub.ru/10.1097/JCP.0000...
I've been using Oxytocin, one squirt per nostril twice a day, for about 8 months. I think it helps calm my body: OxyPure Oxytocin Spray - 12IU walmart.com/ip/OxyPure-Oxyt...