[Correlation study on sensory gating P50 and Wisconsin card sorting test in schizophrenics with violent behaviors].

OBJECTIVE: To analyze the variations of sensory gating and executive functions in schizophrenics with violent behaviors, and the relationship between sensory gating and executive functions. METHODS: Thirty-five schizophrenics with violent behaviors (Group V) and 32 healthy control persons (Group C) were recorded by P50 with EGI 256 high density EEG. They were also examined by Wisconsin card sorting test (WCST) and followed up for 3 months. The relationship of sensory gating P50 and WCST was evaluated by Person's analysis. RESULTS: (1) Compared with Group C, Group V showed a higher amplitude of S2-P50 [baseline: (1.8 ± 1.1) vs (0.9 ± 0.6) µV; 3-month treatment: (1.9 ± 1.6) µV]. There was a higher S2/S1 ratio, a lower S1-S2 difference and 100 × (1-S2/S1) at baseline and after 3 months (P < 0.05) [baseline: S2/S1, S1-S2 and 100 × (1-S2/S1) in both groups respectively [(89 ± 49) vs (42 ± 25), (0.7 ± 2.5) vs (1.4 ± 1.2), (11 ± 49) vs (58 ± 25); 3 months treatment: (170 ± 277, -0.0 ± 1.8, -70 ± 277)]; (2) At baseline and after a 3-month treatment, two groups had no difference in learning [baseline (t = -0.585, P = 0.561), 3 months (t = -0.021, P = 0.983)] (P > 0.05) and there were significant differences in other indices (P < 0.05); (3) No relationship was found between S2/S1 ratio, S1-S2 and WCST in two groups at baseline and after a 3-month treatment by Person's analysis. CONCLUSIONS: The schizophrenics with violent behaviors have sensory gating deficits and abnormal executive functions before and after treatment. Sensory gating and executive functions may reflect different brain functions in schizophrenics.

[Sensory gating P50 in schizophrenic patients with and without homicide].

OBJECTIVE: To investigate the change of sensory gating P50 in schizophrenic patients with and without homicide. METHODS: The auditory evoked potentials P50 were recorded from 26 schizophrenic patients with homicide (Sch group), 27 schizophrenic patients without homicide (non-Sch group) and 32 normal controls (NC) using conditioning/testing paradigm presented with auditory double click stimuli by EGI 256 dense array. And the same time, their clinical symptoms were evaluated by positive and negative symptom scale (PANSS). RESULTS: (1) Compared with NC, two Sch groups showed no significant difference in amplitude and latency of S1-P50 [amplitude: NC, Sch group, non-Sch group at Fz: (2.4 + or - 1.6) microV, (2.5 + or - 1.5) microV, (3.4 + or - 2.7) microV; latency: NC, Sch group, non-Sch group at Fz: (68 + or - 19) ms, (67 + or - 20) ms, (61 + or - 19) ms; respectively], but a higher amplitude and delayed latency of S2-P50 [amplitude: NC, Sch group, non-Sch group at Fz: (0.8 + or - 0.7) microV, (2.5 + or - 1.6) microV, (3.3 + or - 2.2) microV; latency: NC, Sch group, non-Sch group at Fz: (50 + or - 26) ms, (75 + or - 19) ms and (70 + or - 24) ms respectively] (P < 0.01), and no significant difference in amplitude and latency of S2-P50 between two Sch groups. (2) Compared with NC, two Sch groups showed a higher S2/S1 ratio [NC, Sch group, non-Sch group at Fz: 35 + or - 26, 153 + or - 137, 125 + or - 85, respectively], lower S2-S1 [NC, Sch group, non Sch group at Fz: 1.69 + or - 1.55, 0.08 + or - 2.41 and 0.17 + or - 2.30, respectively] and 100 (1-S2/S1) [NC, Sch group, non-Sch group at Fz: 65 + or - 26, -53 + or - 137 and -25 + or - 85 respectively] (P < 0.01). And there was no significant difference in S2/S1 ratio, S2-S1 and 100 (1-S2/S1) between two Sch groups. (3) Two Sch groups showed no significant difference in PANSS total, P scale, N scale, and G scale [Sch group: (110 + or - 27), (26 + or - 10), (29 + or - 7), (55 + or - 12); non Sch group: (105 + or - 27), (24 + or - 8), (28 + or - 10) and (53 + or - 12) respectively] (P > 0.05), and no significant correlation with S2/S1 ratio, S2-S1 and 100(1-S2/S1) (P > 0.05). CONCLUSION: Sensory gating deficit exists in schizophrenic patients with and without homicide. And it can be quantified by measuring auditory evoked potential P50, but sensory gating P50 has no difference between schizophrenic patients with and without homicide.