On Off -- "dopamine overdose hypothesis" -- tremor tydbyt

[aspergerian]

Distinct alterations in Parkinson's medication-state and disease-state connectivity. - tremor.

ncbi.nlm.nih.gov/pubmed/289...

Connections that correlate with only tremor severity are anchored by the cerebellum and the supplemental motor area, but only those connections that include the supplemental motor area predict dopaminergic improvement in tremor. Our results suggest that dopaminergic medications do not simply 'normalize' abnormal brain connectivity associated with Parkinson's disease, but rather dopamine drives distinct connectivity changes, only some of which are associated with improved motor symptoms. In addition, the dissociation between of connections related to severity of bradykinesia/rigidity versus tremor highlights the distinct abnormalities in brain circuitry underlying these specific motor symptoms.

Dopamine-related dissociation of cortical and subcortical brain activations in cognitively unimpaired Parkinson's disease patients OFF and ON medications.

ncbi.nlm.nih.gov/pubmed/300...

Dopamine-related dissociation of cortical and subcortical brain activations in cognitively unimpaired Parkinson's disease patien…ts OFF and ON medic... 2018 "novel support for the dopamine overdose hypothesis"

[sharoncrayn]

the key finding: "dopamine drives distinct connectivity changes, only some of which are associated with improved motor symptoms." IOW, not all dopamine medications are going to show or result in improved motor symptoms (tremors, etc.). Taking things one step further, "connectivity" is an extremely complex issue.

[sharoncrayn]

The 2nd study reinforces what some of us have known for some time, but many PD patients don't understand: "Despite dopaminergic depletion that is severe enough to cause the motor symptoms of Parkinson's disease (PD), many patients remain cognitively unimpaired. " And for that matter, many PD patients still retain sufficient energy levels relative to their age. The latter is often a heresy in some PD forums.

[aspergerian]

See also:

Heterogeneity of cholinergic denervation in

Parkinson’s disease without dementia.

PDF in research gate. Abstract in Pubmed.

[aspergerian]

And:

ncbi.nlm.nih.gov/pubmed/289...