Fig. 4.

3D error, constant error, and variable errors across targets. Filled circles (upper set, solid lines) indicate no-vision, and open circles (lower set, dashed lines) indicate vision. All error lines indicate standard errors combined within and across subjects. 3D error (A) and constant error (B) show similar patterns. Without vision, control subjects had the smallest errors, STN DBS On patients had intermediate errors, and STN DBS Off patients had the largest errors. With vision, errors are markedly reduced for all groups. Controls subjects still have the smallest errors, but the error difference between control subjects and STN DBS Off patients is reduced from that of no vision. (C) Variable errors are smaller than constant errors, and show a different pattern within the PD group. Without vision, control subjects have the smallest variable errors, but unlike for 3D and constant errors, STN DBS Off patients have intermediate errors while STN DBS On patients have the largest errors. With vision, errors are reduced and similar across groups, although PD patients have slightly higher errors than control subjects.