Abstract:

Previous studies have provided evidence regarding changes in executive function in adults and maltreated children with posttraumatic stress disorder (PTSD). However, few studies have examined cognitive function in adolescents with PTSD related specifically to natural disasters. The goal of this current study is to assess the “cold” executive function and “hot” executive function in adolescents with PTSD after experiencing a magnitude 8.0 earthquake in Sichuan, China, 2008. Two experiments were designed to test our hypotheses. In study1, we investigated the “cold” executive function using the classic Stroop task. In study 2, the “hot” executive function was measured with the emotional Stroop task. The current research examined 947 junior high school students using PCL-5 questionnaires designed by trained psychiatrists. Results showed that 44 adolescents (aged 13-17 years) were diagnosed with PTSD after the Sichuan earthquake. The two tasks were administered to three groups of adolescents: (a) 28 PTSD adolescents (14 male, 14 female); (b) 28 non-PTSD adolescents exposed to the same earthquake (14 male, 14 female); (c) 28 healthy adolescents without earthquake experience (15 male, 13 female). In the classic Stroop task, the analysis of variance (ANOVA) of mean reaction time (RT) only revealed a significant effect in congruent color words, indicating that the RTs of incongruent trials were significantly longer than those of congruent trials in all three groups. The Stroop effect on the PTSD group, non-PTSD group and the controlled teenagers showed no significant differences. The results proved that adolescents with PTSD performed similarly to non-PTSD and controlled teenagers in “cold” executive function in the classic Stroop task. In the emotional Stroop task, the ANOVA of mean RT revealed a significant interaction effect between group and word type. The simple effect test showed that the RTs of earthquake-related words of PTSD teenagers were significantly longer than those of positive words and neutral words, while the RTs of earthquake-related words of non-PTSD teenagers were significantly shorter than those of positive words and neutral words. There was no significant effect in the controlled group. In addition, the ANOVA of the emotional Stroop effect revealed a significant interaction effect between group and word type. The simple effect test showed that a more robust earthquake interference effect was obtained than positive words in the PTSD group, while the earthquake interference effect was inferior to the positive words for the non-PTSD group. Once again, there was no significant effect in the controlled group. As a result, the PTSD group performed more poorly in the emotional Stroop task compared with the non-PTSD group and controlled group, exhibiting defects in “hot” executive function. In summary, the current study suggests that adolescents with PTSD relating to a natural disaster have defects only in the emotional control domain of executive function compared with non-PTSD adolescents exposed to the same disaster, and adolescents with no exposure to earthquake experience at all. However, PTSD adolescents do perform well in generic executive function compared to both the non-PTSD and control group.

Key words: PTSD adolescents of earthquake, executive function, the Stroop task, the emotional Stroop task