Table 6. Results of Regressions Predicting Children's Memory from Their Age, Income, and General Sympathetic and Parasympathetic Reactivity.

	Memory Performance
	Free Recall		Total Memory
	Model 1 β	Model 2 β	Model 1 β	Model 2 β
Predictors
Age	.45***	.43***	.58***	.56***
Family income	.16	.17	.23**	.25**
PEP reactivity index	.24**	.25**	.13	.14
RSA reactivity index	−.03	−.03	−.11	−.07
Age × PEP Reactivity Index	—	−.04	—	−.09
Age × RSA reactivity index	—	.07	—	.17*

^*p < .05.

^**p < .01.

^***p < .001.

Note: Family income was scored on an ordinal scale, with 1 = <$10000 and 8 = >$60000. PEP, pre-ejection period and RSA, respiratory sinus arrhythmia. Higher PEP and RSA reactivity indices correspond to greater reactivity or consistent arousal throughout the laboratory protocol.