Fig. 2

Three-way interaction plot of motor symptom asymmetry, UA and sex on cognitive and psychiatric outcomes. Significant three-way interactions were noted for immediate memory (A), delayed memory (B), processing speed (C) and sleepiness (D). Analyses were performed using the PROCESS macro for SPSS (Model 3). Model includes the following covariables: age, education, levodopa medication and racial background. HC healthy controls, HVLT Hopkins Verbal Learning Test, LPD patients with Parkinson’s disease (PD) who exhibit predominantly left-sided motor symptoms, RPD patients with PD who exhibit predominantly right-sided motor symptoms, UA uric acid