Table 1.

Participant characteristics for sample used to examine effect of UCS variations on SCR conditioning (n = 135)

Participant Characteristics	Factor 1: Single UCS vs. Compound UCS			Factor 2:500-msec Shock vs 1000-msec Shock
	Single UCS (n = 70)	Compound UCS (n = 65)	Comparison of two groups	500-msec Shock (n = 69)	1000-msec Shock (n = 66)	Comparison of two groups
Age {Mean (SD), years}	22.9 (10.0)	23.5 (10.0)	t(133) = −0.39, p = .70	23.7 (10.4)	22.7 (9.1)	t(133) = 0.58, p = .56
Gender (% female, n)	54%, n = 38	65%, n = 42	χ2(1, 135) = 1.49, p = .22	61%, n = 42	58%, n = 38	χ2(1, 135) = 0.15, p = .70
Education (% completed college, n)	14%, n = 10	20%, n = 13	χ2(1, 135) = 0.78, p = .38	16%, n = 11	18%, n = 12	χ2(1, 135) = 0.12, p = .73
Ethnicity (% Hispanic, n)	4%, n = 3	11%, n = 7	Fischer’s exact p = .20	9%, n = 6	6%, n = 4	Fischer’s exact p = .74
Race (% African American, n)	6%, n = 4	3%, n = 2	Fischer’s exact p = .68	4%, n = 3	5%, n = 3	Fischer’s exact p = 1.00
Unconditioned Stimulus Intensity {Mean(SD) mA}	1.6 (0.5)	1.7 (0.4)	F(1, 130) < 1, p = ns	1.6 (0.4)	1.7 (0.5)	F(1, 130) < 1, p = ns