Does implicit learning in non-demented Parkinsons disease depend on the level of cognitive functioning?
We investigated the influence of the level of cognitive functioning on sequence-specific learning in Parkinson’s disease (PD). This was done by examining the relationship between the scales for outcomes in Parkinson’s disease-cognition [SCOPA-COG, Marinus, J., Visser, M., Verwey, N. A., Verhey, F. R. J., Middelkoop, H. A. M.,Stiggelbout, A., et al. (2003). Assessment of cognition in Parkinson’s disease. Neurology, 61, 1222-1228] and the serial reaction time (SRT) task [Nissen, M. J., & Bullemer, P. T. (1987). Attentional requirements for learning: Evidence from performance measures. Cognitive Psychology, 19, 1-32] in a homogeneous sample, consisting of 25 PD patients diagnosed in Stage 3 of the Hoehn and Yahr [Hoehn, M. M., & Yahr, M. D. (1967). Parkinsonism: onset, progression, and mortality. Neurology, 17, 427-442] scale. Six patients in the low scoring cognitive group, 11 patients in the average scoring and eight patients in the high scoring group, conducted a SRT task with a determ
