Finally, we addressed the question whether these findings were specific to auditory hallucinations by also taking into account if patients were experiencing other (i.e., visual, olfactory, somatic/tactile, persecutory) but not auditory hallucinations. Because of the small number of patients exhibiting other forms of hallucinations (as indicated by SAPS) prevented forming specific subgroups of comparable size, patients not reporting auditory hallucinatons (NH) were regrouped into those reporting any other hallucinations (OH) and those without reporting any hallucinations (WH). The repeated measures ANOVA for the pooled N1 sink estimates of the combined sample (AH, n = 26; WH, n = 23; OH, n = 26; HC, n = 46) indicated that auditory hallucinators had significantly reduced N1 sinks (AH: −.85 ±1.22) compared to all other groups (WH: −1.52 ±1.16; OH: −1.66 ±1.95; HC: −1.66 ±1.40), who did not differ from each other (between group contrasts: AH vs. WH, F[1,117] = 3.78, p = .05, AH vs. OH, F[1,117] = 5.90, p = .02, AH vs. HC, F[1,117] = 7.38, p = .008; all other, F[1,117] < 1.0, n.s.).
