Table 2.

Coefficients in regression models

Model	Beta (SE)	Beta′	t	p
1b
1
Age	0.013 (0.004)	0.574	2.844	0.010
GM	0.344 (0.857)	0.081	0.402	0.692
2
Age	0.018 (0.004)	0.815	4.612	0.0002
GM	−0.918 (0.775)	−0.216	−1.185	0.251
Glutamate	0.261 (0.076)	0.640	3.446	0.003
GABA	−0.121 (0.060)	−0.321	−2.003	0.060
2b
1
Age	0.009 (0.005)	0.382	1.704	0.103
GM	0.237 (1.004)	0.053	0.236	0.816
2
Age	0.016 (0.004)	0.674	3.583	0.002
GM	−1.262 (0.870)	−0.282	−1.451	0.163
Glutamate	0.297 (0.085)	0.690	3.489	0.002
GABA	−0.190 (0.068)	−0.480	−2.812	0.011
3b
1
Age	0.007 (0.005)	0.337	1.473	0.156
GM	0.735 (0.905)	0.186	0.812	0.426
2
Age	0.014 (0.004)	0.670	3.947	0.001
GM	−0.702 (0.694)	−0.178	−1.012	0.324
Glutamate	0.275 (0.068)	0.724	4.053	0.0007
GABA	−0.216 (0.054)	−0.617	−4.004	0.0008

Dependent variable: PCC/PCu deactivation during WM task; model 1 predictors: (constant), age, GM; model 2 predictors: (constant), age, GM, glutamate, GABA.

Beta (SE), unstandardized coefficient (SE); and beta′, standardized coefficient.