Fig. 5

Microstructural alterations within the LC and LC-M1 tract correlate with LC-noradrenergic neuronal loss. a Increased FA of the LC was significantly correlated with reduced LC cell density in the whole cohort. Upper inserted image was from a control case showing low FA of the LC with high LC-noradrenergic cell density, lower image was from a PD case showing high FA of the LC with only a few LC-noradrenergic cells. Scale bar, 100 µm. b Increased LC FA was significantly correlated with reduced LC noradrenergic fiber load in the whole cohort. c Increased FA of the LC-DLPFC tract was significantly correlated (uncorrected) with reduced LC-noradrenergic fiber load in the LC of AD and control cases. d Increased FA of the LC-M1 tract was significantly correlated (uncorrected) with reduced noradrenergic cell density in the LC in PD and control cases