ABSTRACT
Objective:To explore the impact of negation effect on color judgment of the color-word pairs and the impairment of cognitive inhibition function of the patients with schizophrenia (SCH) through embedding negation into the Stroop task.Methods:From January to December 2021, " Affirmative/ negative + color words" as the experimental materials, classical Stroop paradigm as the experimental paradigm, a mixed experimental design of 2 (groups: the SCH group vs the normal control group)×2(phrase polarity: affirmative phrases vs negative phrases)×2 (word-color congruence: consistency vs inconsistency) was designed to explore the inhibition function of negative phrases of the SCHs under bipolar negation conditions (Experiment 1) and multi-polar negation conditions (Experiment 2) respectively. The schizophrenic patients in Experiment 1(28 patients and 28 normal controls) and Experiment 2(30 patients and 30 normal controls) were sampled from the inpatients of Tangshan Kailuan Mental Health Center and Suzhou Guangji Hospital respectively, and the healthy controls were recruited from the community. SPSS 25.0 software was adopted as statistical analysis, and accuracy, response time of Stroop and the Stroop effect were analyzed by repeated measurement analysis of variance. Results:(1) The group main effects of response time were both significant in bipolar negation conditions(Experiment 1) ( F=49.22, P<0.001, ηp2=0.48) and multi-polar negation conditions (Experiment 2) ( F=37.58, P<0.001, ηp2=0.39). In bipolar negation (Experiment 1) conditions, as for the Stroop effect of response time, there was a significant interaction between the groups and polarities( F=4.42, P<0.05, ηp2=0.08), and there was a statistically significant difference between the affirmative Stroop effect (-0.137±0.522)and the negative Stroop effect(0.082±0.169) in the schizophrenia group( F=7.15, P<0.05, ηp2=0.12). In multi-polar negation conditions (Experiment 2), there was a marginal significant of the interaction between Stroop conditions and polarities in accuracy( F=3.81, P=0.056, ηp2=0.06). The accuracy under the word color consistency condition was higher than that under inconsistency condition((96.51±1.55)%, (90.00±2.54)%) ( F=5.15, P<0.05, ηp2=0.08). (3)In bipolar negation (Experiment 1) conditions, as for the accuracy, the interaction among groups, word color consistencies, and polarities was significant( F=6.66, P<0.05, ηp2=0.11). The interaction between word color consistencies and polarities was significant in the schizophrenia group( F=9.16, P<0.05, ηp2=0.15). In the normal group, the interaction between Stroop conditions and polarities was not significant( P>0.05). Conclusion:The impairment of cognitive inhibition function in schizophrenia is severe, which is reflected in negative processing; negation functions as cognitive inhibition, which is particularly prominent in bipolar negation.