N100 Repetition Suppression Indexes Neuroplastic Defects in Clinical High Risk and Psychotic Youth

Table 1

Demographic and clinical characteristics of clinical groups.

Variable	Clinical group
	PS			CHR			HC
	()			()			()
	%	M	SD	%	M	SD	%	M	SD
Demographics
Male (% male)	86.4			44.8			52.9
Age (years)		11.4	2.8		13.5	2.7		11.0	4.2
Race/ethnicity (% non-Hispanic White)	95.2			79.3			94.1
Handedness (% left-handed)	13.6			6.9			5.9
SIB-R SS		75.6	27.9		89.6	13.0		107.1	20.9
First-degree family mental health history
Psychosis	14.3			4.4			0
Nonpsychotic major depression	14.3			21.7			0
Nonpsychotic bipolar disorder	4.8			17.4			11.8
Medication use at assessment
Antipsychotic(s)	50.0			27.6			0
Antidepressant(s)	45.5			31.1			0
Mood stabilizer(s)	18.2			6.9			0
Benzodiazepine(s)	4.5			3.5			0
Stimulant(s)	4.5			0			0

Note: PS, psychosis; CHR, clinical high risk; HC, healthy control; SIB-R SS, Scales of Independent Behavior-Revised scaled scores.
Groups noted by different superscripted letters were significantly different in post hoc pairwise Student-Newman-Keuls (SNK) tests for continuous variables and Bonferroni corrected () Fisher’s exact tests for categorical variables. The SIB-R was administered to 20 PS participants, 21 CHR participants, and 16 HC participants. One PS participant and six CHR participants were unable to provide information about family history of mental illness because they had limited contact with their biological parents or their adoptive parents were unsure of mental illness history among first-degree biological relatives.