(PS9-48) Unitary Cognitive Control and Suicide Risk: An Emphasis on Interpersonal Stress

Purpose
Suicide is a global health concern involving complex decision-making processes, which may be better understood through basic cognitive functions—such as inhibition, cognitive flexibility, and working memory—that collectively form cognitive control. However, past research has often treated these sub-functions in isolation, which may be misleading. For example, difficulty inhibiting negative information, combined with cognitive flexibility, may facilitate maladaptive thinking patterns that contribute to suicidal thoughts and behaviors (STBs). Additionally, research has largely overlooked how stress susceptibility moderates the relationship between cognitive control and suicide risk. Leveraging an experimental design, this study modeled cognitive control as a latent construct comprising inhibition, working memory, and cognitive flexibility and examined its interaction with susceptibility to interpersonal stress in relation to lifetime STBs.

Methods
Participants were 72 undergraduate students (75% Female, 48.9% non-White; Mage = 19.69, SDage = 1.33) with lifetime history of STBs. They completed behavioral tasks assessing inhibition, cognitive flexibility, and working memory, presented in a randomized order. Susceptibility to interpersonal stress was assessed via mood changes before and after a stress interview. Data were analyzed using causal indicator models within a structural equation modeling framework, with cognitive control as a latent variable and susceptibility to interpersonal stress as a moderator.

Results
The latent interaction model fit significantly better than the main effect model, χ2 (df = 20) = 388.598, p < .001. Inhibition (B = .550, β = .571, p <.001, 95% CI [.333, .767]) and cognitive flexibility (B = .298, β = .312, p <.001, 95% CI [.117, .478]) were significant casual indicators of cognitive control, whereas working memory was not (B = .152, β = .209, p =.075, 95% CI [-.015, .320]). There was a significant interaction between latent cognitive control and interpersonal susceptibility on STBs (B = .396, β = .192, p <.001, 95% CI [.318, .474]. Simple slope analysis showed that the protective effects of cognitive control on STBs was attenuated across all levels of interpersonal susceptibility.

Discussion
Findings provide partial support for cognitive control as a causally indicated construct and suggest that its influence on STBs is moderated by susceptibility to interpersonal stress. The significant results indicate that clinical interventions that target the causal indicators, specifically inhibition and cognitive flexibility, should have direct effects on cognitive control, and thereby help reduce suicide risk. Furthermore, the results support the importance of interpersonal stress management in relation to suicide risk.