Overview
Parkinsonism can be caused by medications, particularly those affecting dopamine pathways. Levodopa, a common treatment for Parkinson's disease, can lead to levodopa-induced dyskinesia (LID) in the long term 1. Dopamine signaling in the prefrontal cortex is crucial for cognitive functions like working memory and can be disrupted in conditions such as Parkinson's disease 2.Diagnosis
Functional brain mapping techniques (fMRI, EEG, PET, SPECT, TMS) can explore motor network abnormalities associated with LID 1.
Patients with LID may show increased motor-related activation and functional connectivity in motor and premotor cortical areas and the putamen after levodopa intake compared to PD patients without LID 1.
Decreased activation in the right inferior frontal cortex has been observed in LID patients 1.
TMS studies suggest increased cortical excitability and blunted cortical plasticity in LID patients 1.Management
Levodopa and dopamine agonists are used to treat Parkinson's disease but can cause LID 1.
Repetitive TMS of prefrontal motor control areas and the cerebellum may produce transient anti-dyskinetic effects 1.Key Recommendations
Functional brain mapping techniques can be used to explore motor network abnormalities associated with levodopa-induced dyskinesia (LID) 1. (Evidence: Moderate)
Repetitive transcranial magnetic stimulation (TMS) of prefrontal motor control areas and the cerebellum may offer transient anti-dyskinetic effects in patients with LID 1. (Evidence: Weak)
Optimal prefrontal dopamine signaling, particularly via D1 receptors, is linked with peak cognitive function, such as working memory 2. (Evidence: Moderate)References
1 Chen Thomsen BL, Vinding MC, Meder D, Marner L, Løkkegaard A, Siebner HR. Functional motor network abnormalities associated with levodopa-induced dyskinesia in Parkinson's disease: A systematic review. NeuroImage. Clinical 2024. link
2 Weber MA, Conlon MM, Stutt HR, Wendt L, Ten Eyck P, Narayanan NS. Quantifying the inverted U: A meta-analysis of prefrontal dopamine, D1 receptors, and working memory. Behavioral neuroscience 2022. link