Home-based online line bisection test detects visuo-spatial neglect and pseudoneglect in Parkinson's disease

Parkinson's Disease (PD) may lead to cognitive symptoms, including visuo-spatial attentional deficits such as unilateral spatial neglect (USN). Although there is some evidence for USN in PD patients, especially in those with left-sided onset of motor-symptoms (LPD), previous studies revealed inconsistent and highly variable results in neglect tasks using line bisection and have not systematically compared LPD with RPD (PD patients with right-sided onset) or healthy controls (HC).

We designed a fully automatized online web-based line bisection task and tested a group of 170 PD patients (81 RPD, 66 LPD) and 45 HC.

Our data reveals (1) a rightward bias on line bisection in LPD compared to HC and RPD, (2) right-sided pseudoneglect in HC as well as RPD. Our data also reveals that (3) PD patients, independent of the primarily affected side, are more variable in their line bisections.

These data provide robust evidence for systematic changes in visuo-spatial perception in PD and present a new online diagnosis and monitoring tool for USN to evaluate patients at their home.