Table I.

Demographic, neuropsychological, clinical, and control measures of the total sample and the small (sHCV) and large hippocampal volume groups (lHCV)

	Total sample (N = 58)		sHCV group (N = 29)		lHCV group (N = 29)		Inferential statistics sHCV vs. lHCV
	M	SD	M	SD	M	SD
Age (years)	21.64	2.57	21.97	2.21	21.45	2.23	t(1,56) = 0.71, P = 0.48
Sex: female/male	20/39		10/19		10/19		χ2 (1) = 0.00, P = 1.00
Education (years)	12.29	1.81	12.54	1.64	12.14	1.94	t(1,55) = −0.31, P = 0.76
Intelligencea	114.61	13.34	114.86	14.83	114.39	12.21	t(1,54) = 0.97, P = 0.34
Memoryb
Immediate recall	60.91	8.93	60.79	8.64	61.55	9.05	t(1,55) = −0.96, P = 0.34
Delayed recall	13.58	2.15	13.40	2.00	13.92	2.23	t(1,48) = −0.61, P = 0.54
Difference short	1.23	1.75	1.48	1.55	1.03	1.94	t(1,54) = 0.49, P = 0.63
Difference long	0.73	1.86	0.96	1.33	0.50	2.30	t(1,47) = 0.29, P = 0.77
Childhood traumac	7.56	1.85	7.78	2.24	7.35	1.37	t(1,55) = 1.13, P = 0.27
Trait‐Anxietyd	35.82	8.57	35.39	7.44	36.39	9.79	t(1,54) = 0.37, P = 0.71
Chronic stresse	1.35	0.53	1.32	0.53	1.39	0.54	t(1,56) = −0.42, P = 0.68
US‐intensity	7.12	0.59	7.12	0.60	7.12	0.55	t(1,56) = −0.20, P = 0.85
US‐unpleasantness	6.86	1.03	6.81	1.03	6.87	1.04	t(1,51) = −0.09, P = 0.93
US‐SCR (μS)	0.26	0.16	0.23	0.14	0.30	0.18	t(1,51) = 0.46, P = 0.65

sHCV, relatively small hippocampal volume; lHCV, relatively large hippocampal volume.

^aCulture Fair Intelligence Test (CFT‐20).

^bCalifornia Verbal Learning Test (CVLT); difference short, difference between immediate free recall and short delayed free recall; difference long, difference between immediate free recall and long delayed free recall.

^cChildhood Trauma Questionaire (CTQ).

^dState‐Trait‐Anxiety Inventory (STAI).

^eTrier Inventory for Assessment of Chronic Stress (TICS); US, Unconditioned Stimulus; SCR, Skin Conductance Response.