Fig. 3.

Positive relationship between apathy levels and white matter disturbance in the three tracts of interest.

Bivariate plot displaying the significant association between global apathy and mean diffusivity (MD) in the (A) right frontostriatal tract (FST) and (B) right uncinate fasciculus (UF). Apathy is measured with the short-form Lille Apathy Rating Scale (LARS-s), ranging from −15 to +15, where larger and more positive scores indicate more severe apathy. Larger MD values indicate more severe damage to white matter microstructure. Bivariate plots displaying the associations between apathy domains and the MD of the dorsolateral prefrontal cortex to caudate nucleus tract (dlPFC-cn), FST, and UF, respectively. Cognitive apathy demonstrated a strong association with both the left dlPFC-cn (C) and right FST (D), while auto-activation deficit exemplified a significant relationship with the right UF (E). Correlation coefficients (r) and raw P-values (P) for each hemisphere are shown in upper left. Linear regression line is fit for each scatterplot to aid interpretation. *P-value survives false discovery rate correction at q = 0.05.