Objective
This study aimed to discover the complicated effects of impulsivity and traumatic stress on suicidal ideation mediated by negative cognitive processing bias and depression, through which we may detect the suicide signs as early as possible, to advance the preventive measures.
Methods
We recruited 1,798 undergraduates as participants. Self-rating Idea of Suicide Scale (SIOSS), Barratt’s Impulsiveness Scale (BIS), Negative Cognitive Processing Bias Questionnaire (NCPBQ), and PTSD Checklist Civilian Version (PCL-C) were applied as measuring tools. A moderated mediation latent path model was conducted, among which negative cognitive processing bias and depression were mediation variables and traumatic stress was moderation variable.
Results
Impulsivity was considered separately as three dimensions, namely, non-planning, motor and cognitive impulsivities. We found that all the models fitted well (RMSEA < 0.08, CFI > 0.90, TLI > 0.90, and SRMR < 0.08), in which traumatic stress moderated the direct effects of depression on suicidal ideation (p < 0.01, p < 0.001). For the model of non-planning and cognitive impulsivities, traumatic stress also moderated the effects of impulsivities on depression (p < 0.01) and of negative cognitive processing bias on suicidal ideation (p < 0.05). The simple indirect paths of “impulsivity→negative cognitive processing bias→suicidal ideation” and “impulsivity→depression→suicidal ideation” and the chain indirect path of “impulsivity→negative cognitive processing bias→depression→suicidal ideation” were all significant (p < 0.001) on different (i.e., high, medium, and low) levels of traumatic stress. Traumatic stress positively moderated the indirect effects (p < 0.001, p < 0.01, p < 0.05) except for the path of “motor impulsivity→negative cognitive processing bias→suicidal ideation”.
Conclusions
The present study confirmed that negative cognitive processing bias and impulsivity were closely correlated and worked together as trait-like vulnerability-schema structures in the development of suicidal ideation. For suicide prevention, we could monitor the dynamics of the vulnerability-schema structure and intervene in negative cognitive processing bias, which was easier and more practical to change compared with impulsivity. This might advance the time course of finding the suicide signs.
