Table 1.

Performance of the five FG-based models plus the Ensemble one to estimate brain age in terms of MAE and $R^2$. The last four rows provide the CAPB, CAPA, CADB and CADA, respectively. The best performing model is identified by star symbol. The last four rows provide the CAPB, CAPA, CADB and CADA, respectively. The best performing model is identified by star symbol.

Matrices	Association	Brainstem	Commissural	Limbic	Projection	Ensemble
Mean ${\text{R}}^2$	0.26	0.11	0.26	0.29	0.25	$\star$ 0.42
STDV ${\text{R}}^2$	0.02	0.01	0.01	0.02	0.03	0.015
Mean MAE	5.24	5.86	5.23	5.08	5.28	$\star$ 4.55
STDV MAE	0.1	0.09	0.11	0.12	0.13	0.08
CAPB	0.51	0.33	0.51	0.54	0.5	0.65
CAPA	0.91	0.95	0.91	0.9	0.91	0.89
CADB	$-$ 0.85	$-$ 0.94	$-$ 0.86	$-$ 0.83	$-$0.86	$-$0.75
CADA	$-$ 0.001	$-$ 0.003	$-$ 0.001	$-$ 0.001	$-$ 0.001	$-$ 0.006