Fig. 2.

Density plots of longitudinal cognitive changes versus age and log transformed baseline WMH load. The colors indicate predicted cognitive scores by the mixed effects models, with warmer colors representing higher scores, and cooler colors representing lower scores. The transparency in the figures indicates the density of the data, i.e. areas of low transparency indicate regions where there are no subjects and the model is extrapolating (e.g. young subjects with high WMH loads, or old subjects with low WMH loads). The contour lines imply the direction of changes (i.e. horizontal orientation indicates predominance of age effects and vertical orientation indicates predominance of WHM load effects). WMH=White Matter Hyperintensities. HC = Healthy Control. PD = Parkinson's Disease. MoCA = Montreal Cognitive Assessment Score. HVLT = Hopkins Verbal Learning Test Revised Total Score. Benton = Benton Judgement of Line Orientation Score. Exec = Executive Function Score.