Figure 2From: Components of acquisition-to-acquisition variance in continuous arterial spin labelling (CASL) imagingPrincipal components maps. From top to bottom, component images of the first four components of acquisition-to-acquisition variance, overlaid on template brains. On the right, histograms of the component scores (unitless). The scale and sign of these images is arbitrary. The coefficients of the first component are positive across the brain; for better contrast, a different colour scale was used than for the remaining components.Back to article page