Randomized trial of cognitive speed of processing training in Parkinson disease

Objective: To examine the efficacy of cognitive speed of processing training (SOPT) among individuals with Parkinson disease (PD). Moderators of SOPT were also examined. Methods: Eighty-seven adults, 40 years of age or older, with a diagnosis of idiopathic PD in Hoehn & Yahr stages 1-3 and on a stable medication regimen were randomized to either 20 hours of self-administered SOPT (using InSight software) or a no-contact control condition. Participants were assessed at baseline and after 3 months of training (or an equivalent delay). The primary outcome measure was useful field of view test (UFOV) performance, and secondary outcomes included cognitive self-perceptions and depressive symptoms. Results: Results indicated that participants randomized to SOPT experienced significantly greater improvements on UFOV performance relative to controls, Wilks lambda = 0.938, F (1,72) = 4.79, p = 0.032, partial eta(2) = 0.062. Findings indicated no significant effect of training on secondary outcomes, Wilks lambda = 0.987, F-2,F-70 < 1, p = 0.637, partial eta(2) = 0.013. Conclusions: Patients with mild to moderate stage PD can self-administer SOPT and improve their cognitive speed of processing, as indexed by UFOV (a robust predictor of driving performance in aging and PD). Further research should establish if persons with PD experience longitudinal benefits of such training and if improvements translate to benefits in functional activities such as driving. Classification of evidence: This study provides Class III evidence that SOPT improves UFOV performance among persons in the mild to moderate stages of PD.