Objective: To get new insights into the role of oscillatory brain activity recorded non-invasively in patients with Parkinson’s disease (PD) and impulse control disorders (ICDs).

Background: ICDs is commonly associated with dopaminergic agonist (DA) treatment and trait impulsivity. Other psychiatric and neurological disorders related with impulsivity has shown alterations in brain oscillations (cortical θ and β, and the θ/ β ratio). In these disorders, β oscillations is correlated with ICD severity and an increased θ/ β ratio is associated with higher risk-taking behaviours.

Method: We included 36 participants divided into three groups: healthy controls (HC) (n=12), patients with PD and ICDs (PD+ICDs) (n=12) and patients with PD without ICDs (PD-ICDs) (n=12). Resting state EEG was collected from the 3 groups. PD patients underwent two recording sessions, one under their regular dopaminergic treatment (ON) and another after an overnight washout of their usual dopamine replacement therapy (OFF). Independent component analysis was used for blind source separation and spectral decomposition focused our analysis on the study of differences in three variables: θ and β, and the θ/β ratio.  Correlation analysis of clinical features and demographic information with the EEG variables was also conducted. Source localizations of these three measures of interest were estimated with low resolution brain electromagnetic tomography (sLORETA).

Results: Increased θ power in the central region was observed in PD+ICDs patients in the OFF condition compared to HC (p=0.005). These patients also showed decreased central θ activity (p= 0.007) and θ/β ratio (p=0.023), as well as increased central-parietal β activity (p=0.036) in ON. Trait impulsivity correlated with frontal θ/β ratio (p=0.006) in ON condition PD+ICDs, and with frontal (p=0.026) and parietal θ/β (p=0.039) in OFF condition PD-ICDs. We detected differences in central θ between PD+ICDs in OFF and HC in frontal regions; and in PD+ICDs ON and OFF condition. Also, parietal sources of β oscillations showed a treatment effect in the PD+ICD group with increased β activity.

Conclusion: PD+ICDs patients show a distinctive neurophysiological profile compared to patients with ICD and this profile is sensitive to dopaminergic treatment. The profile found shares similarities with other disorders with high trait impulsivity.

« Back to MDS Virtual Congress 2021

MDS Abstracts - https://www.mdsabstracts.org/abstract/a-neurophysiological-profile-associated-with-impulse-control-disorders-in-parkinsons-disease/