Table 1.

Descriptive Statistics and Correlations for the 8 Variables Included in the Current Study

Variable	n	M	SD	Range	2	3	4	5	6	7	8
1. Age	191	17.32	1.18	13–19	0.02	−0.09	−0.12	0.15	0.13	−0.09	−0.17
2. IQ	178	92.80	12.06	63–140		0.11	0.19	0.02	−0.01	0.05	−0.15
3. Substance Use	184	5.52	2.70	0–11.40			−0.01	−0.06	−0.11	0.27*	0.28*
4. Brain Volume	191	1266.47	99.55	1031–1533				−0.25*	−0.34*	−0.03	0.02
5. GMV Amygdala	191	15.71	0.82	13.32–17.94					0.16	−0.20	−0.07
6. GMV Hippocampus	191	7.60	0.76	5.53–9.73						−0.12	−0.23*
7. Fearlessness	191	5.14	2.55	0–11							0.48*
8. Disinhibition	191	5.41	1.68	0–8

Note. Age = chronological age in years; IQ = estimated full scale Wechsler IQ; Substance Use = regular substance use; Brain Volume = total brain volume (white + gray matter); GMV Amygdala = average gray matter volume for left and right amygdala x 100; GMV Hippocampus = average gray matter volume for left and right hippocampus ×100; Fearlessness = fearlessness temperament dimension; Disinhibition = disinhibition temperament dimension; n = number of non-missing cases; M = mean, SD = standard deviation; Range = range of scores in current sample.

^*p < .0018 (Bonferroni-corrected alpha: .05 / 28 correlations).