Table 2.

Descriptive indices of ERP components for contamination and neutral cues in two groups of individuals with contamination OCD and healthy control.

Component		P2		N2		P3		ELPP
Electrode	Group	Mean		Mean		Mean		Mean
		Contamination	Neutral	Contamination	Neutral	Contamination	Neutral	Contamination	Neutral
Fz	Obsession	2.85	2.55	−3.11	−0.47	4.24	1.99	−0.62	−0.56
	Normal	2.23	2.12	−0.93	−0.39	1.67	1.24	0.84	0.12
Cz	Obsession	2.96	2.81	−2.61	−1.99	3.76	3.10	−0.59	−0.46
	Normal	2.75	2.69	−1.49	−1.76	2.78	2.68	−0.07	−0.08
Pz	Obsession	3.00	2.89	−2.23	−1.16	3.33	3.01	−0.86	−0.87
	Normal	2.98	2.85	−1.51	−1.28	2.32	2.34	−0.06	−0.54
F3	Obsession	3.11	3.06	−1.61	−1.29	2.87	2.75	0.33	0.32
	Normal	2.79	2.57	−1.53	−1.33	2.46	2.11	−0.17	−0.14
F4	Obsession	3.57	3.48	−1.30	−0.88	3.17	3.13	0.32	0.31
	Normal	2.98	3.05	−1.36	−0.80	2.17	2.53	0.19	0.20
C3	Obsession	3.00	2.89	−1.50	−1.45	3.16	3.07	−0.38	−0.18
	Normal	2.78	2.79	−0.08	−0.50	2.64	2.67	−0.05	0.08
C4	Obsession	3.31	3.19	−1.28	−1.18	3.55	3.46	−0.37	0.09
	Normal	3.16	3.22	−1.16	−1.01	3.36	3.11	−0.02	0.09
P3	Obsession	3.68	3.36	−0.62	−0.46	4.40	3.75	−0.49	−0.36
	Normal	3.34	3.14	0.30	0.09	3.74	3.64	−0.45	0.09
P4	Obsession	4.22	4.18	−0.57	−0.49	4.37	4.27	−0.82	−0.66
	Normal	3.57	3.48	−0.21	−0.24	3.63	3.56	−0.48	−0.44

P2 = positive component 2; N2 = negative component 2; P3 = positive component 3; ELPP = early lateral positivity peaket; Fz = frontal midline; Cz = central midline; Pz = parietal midline; F3/F4 = left and right sides of the frontal lobe, respectively; C3/C4 = left and right sides of the central lobe, respectively; P3/P4 = left and right sides of the parietal lobe, respectively.