5 - (3-MIN 2) Nonlinear Escalation of Suicidal Ideation: Testing a Threshold Model of Cognitive-affective Instability

Suicidal ideation in adolescence is typically conceptualized and modeled as a linear function of cognitive vulnerability (e.g., hopelessness) and affective distress. However, clinical observation and ecological data suggest that suicidal thoughts often emerge abruptly rather than gradually, consistent with nonlinear threshold processes. Drawing on dynamic systems theory and catastrophe models, the present study tests whether suicidal ideation reflects a nonlinear “phase transition” resulting from the interaction of cognitive hopelessness and affective instability.
A sample of 212 adolescents (ages 14–18) with elevated depressive symptoms completed ecological momentary assessment (EMA) surveys three times daily for 30 days assessing suicidal ideation, hopeless cognitions, and negative affect intensity. Multilevel cusp catastrophe modeling was used to compare linear, quadratic, and nonlinear threshold models of suicidal ideation. In this framework, hopelessness was specified as the asymmetry (bifurcation) variable and affective instability as the control variable hypothesized to produce sudden shifts in ideation once a critical threshold was crossed.
Results indicated that the cusp catastrophe model provided superior fit relative to linear and quadratic models. Suicidal ideation remained relatively stable at low levels of affective instability; however, when negative affect variability increased beyond a critical value in the context of elevated hopelessness, abrupt discontinuous increases in ideation were observed. These findings suggest that suicidal ideation may not simply intensify proportionally with distress, but instead may “flip” into high-risk states when cognitive and affective systems destabilize.
Conceptually, this model challenges traditional linear mediation frameworks in CBT research and highlights the importance of identifying destabilizing conditions preceding rapid escalation. Clinically, findings underscore the need for interventions that target both cognitive vulnerability (e.g., hopeless belief structures) and affect regulation processes to prevent threshold crossings. Monitoring affective volatility in real time may allow for earlier detection of imminent risk states.
By applying nonlinear dynamic modeling to adolescent suicide risk, this study advances a precision-oriented, mechanism-focused framework for understanding abrupt changes in suicidal ideation and offers novel implications for sustainable, equitable CBT interventions that prioritize early destabilization detection.