Figure 3.

Regressions of R₁ with CBF (n=67). Results are shown for six brain ROIs associated with particular structures. For each ROI, results are shown for CBF values derived from grey or white matter. The coefficient of determination, R², of the multiple linear regression model is reported with the symbol *, indicating significance at p<0.01. Except the whole brain and cerebellum WM, all ROIs exhibited significant positive correlations between R₁ and CBF. Note that analysis was restricted to WM ROIs for R₁ and to cortical GM or WM for CBF. CBF, cerebral blood flow; R₁, longitudinal relaxation rate; ROI, region of interest.