Table 1.

Participant demographics and clinical characteristics

	Sample 1 (n=43)	Sample 2 (n=38)
Demographics	Mean (SD) or %	Mean (SD) or %
Age (years)	25.2 (7.6)a	31.2 (11.9)a
Sex (% female)	68.2%a	70.7%a
Race (% Caucasian)	61.9%a	52.5%a
Clinical Variables
Current Major Depressive Disorder	36.6%a	53.7%b
Current Anxiety Disorder	58.1%a	31.7%b
Current Comorbid Anxiety Disorders	27.9%a	0.0%b
Current Comorbid Depression and Anxiety	44.2%a	31.6%a
Lifetime Major Depressive Disorder	51.2%a	53.7%a
Lifetime Anxiety Disorder	62.8%a	31.7%b
Lifetime Alcohol Use Disorder	9.3%a	26.3%b
Lifetime Substance Use Disorder	11.6%a	31.6%b
Taking Psychiatric Medication	0.0%a	10.5%b
Startle Variables
Startle Potentiation to U-Threat	12.9 (22.1)a	18.7 (19.4)a
Startle Potentiation to P-Threat	16.4 (28.0)a	19.0 (17.3)a
IAPS fMRI Image Ratings Arousal (Mean; Range)
U-threat Negative Images	-	4.9 (1.9); 1.0 – 8.9
U-threat Neutral Images	-	2.7 (1.7); 1.0 – 7.4
P-threat Negative Images	-	4.7 (1.9); 1.0 – 8.9
P-threat Neutral Images	-	2.8 (1.6); 1.0 – 7.2
Valence (Mean; Range)
U-threat Negative Images	-	3.3 (1.4); 1.2 – 8.5
U-threat Neutral Images	-	5.8 (0.9); 4.0 – 8.1
P-threat Negative Images	-	3.3 (1.4); 1.0 – 8.4
P-threat Neutral Images	-	5.7 (0.9); 4.1 – 7.7

Note. Means (and standard deviations) or percentages with different subscripts across rows were significantly different in pairwise comparisons (p < .05, chi-square test for categorical variables and Tukey’s honestly significant difference test for continuous variables). IAPS = International Affective Picture System.