Table 5.

Moderated mediation models examining the mediating effect of ventromedial caudate microglial activation (PAM) on the relationship between physical activity and (Model 3, N = 134) global cognitive outcomes or (Model 4, N = 131) synaptic integrity markers in the VM caudate

	Effect	SE	p	95% CI
Moderation effect (physical activity × microinfarct → PAM VM caudate)
Age	0.001	0.002	0.16	−0.0004, 0.0026
Sex	0.004	0.009	0.63	−0.0136, 0.022
Education	0.001	0.0017	0.32	−0.002, 0.005
motor10	0.033	0.031	0.30	−0.030, 0.095
Microinfarcts	0.044	0.018	0.016	0.008, 0.079
Physical activity	−0.003	0.005	0.51	−0.013, 0.006
Physical activity × microinfarcts	−0.015	0.007	0.042	−0.030, −0.005
Model 3: Direct effect (physical activity → cognition)
Age	0.005	0.002	0.001	0.002, 0.008
Sex	−0.009	0.017	0.61	−0.043, 0.026
Education	−0.007	0.003	0.058	−0.013, 0.0002
motor10	0.10	0.057	0.078	−0.012, 0.216
PAM VM caudate	0.005	0.17	0.98	−0.330, 0.339
Physical activity	0.020	0.008	0.010	0.005, 0.035
Model 3: Conditional indirect effects (physical activity → PAM VM caudate → cognition, with or without microinfarcts)
Index of moderated mediation	Index: −0.001	0.0024	—	−0.004, 0.005
Microinfarcts			—
No	0.000	0.009		−0.002, 0.002
Yes	−0.001	0.003		−0.005, 0.006
Model 4: Direct effect (physical activity → synapse VM caudate)
Age	0.018	0.014	0.19	−0.009, 0.045
Sex	0.073	0.159	0.65	−0.243, 0.388
Education	0.068	0.032	0.63	−0.003, 0.005
motor10	0.029	0.032	0.04	0.004, 0.132
PAM VM Caudate	−1.685	1.557	0.28	−4.77, 1.40
Physical activity	0.084	1.39	0.16	−4.72, 0.771
Model 4: Conditional indirect effects (physical activity → PAM VM caudate → synapse VM caudate, with or without microinfarcts)
Index of moderated mediation	Index: 0.0234	0.0261	—	−0.021, 0.082
Microinfarcts			—
No	0.005	0.012		−0.016, 0.036
Yes	0.029	0.030		−0.026, 0.094

Models estimated indirect effects of PAM VM caudate (mediation) conditional on microinfarct burden (moderation) using 5000-sample bootstrapping.