Pathways to Suicidality: Negative Urgency, Neural Threat Processing, and Daily Social Rejection in Young Adults

/ABSTRACT Suicide is the second leading cause of death among young adults ages 15-241, with rates continuing to rise2. While research has identified some broad predictive factors3, our ability to predict who will experience suicidal thoughts and behaviors (STB) and when these crises will occur remains limited4. This challenge stems from the fact that suicide risk fluctuates dramatically in response to emotional and interpersonal distress5,6, with social threats often acting as precipitating events7,8. The tendency to respond impulsively to negative emotions (e.g., negative urgency9) may help explain why some individuals engage in STB as a maladaptive attempt to escape emotional pain following social threat or rejection. Evidence from neuroscience indicates that social- affective circuitry reflects subjective affective sensitivity to social threat10,11, and overlaps with putative neural correlates of negative urgency12,13, suggesting a potential neural profile that may drive associations between social threat and STB. To test this, I will utilize data from an ongoing R01 including 6 months of ecological momentary assessment (EMA), a personalized peer social feedback fMRI task, and self-report questionnaires from 150 young adults (ages 18-30) with chronic STB to examine how function in social-affective systems and real-world experiences of social threat interact to predict STB. The Specific Aims of this study are to: (1) test associations between negative urgency and STB using both baseline and prospective EMA assessments; (2) investigate associations between functional connectivity of social-affective systems during social threat and trait-level negative urgency; and (3) examine whether individual differences in neural response to social threat moderate same-day relationships between social rejection-generated negative affect and suicidal thoughts. This project, and the associated F31 fellowship at the University of Pittsburgh, will provide critical training for the applicant to become an independent researcher investigating how neural and behavioral responses to social contexts influence suicide risk during key developmental periods. To accomplish the proposed research, this application includes a comprehensive training and mentorship plan that builds on the applicant’s prior clinical psychology and developmental neuroscience training. These Training Goals will focus on expanding the applicant’s knowledge and/or skills in: (1) neurodevelopmental pathways to suicide; (2) negative urgency as a mechanism of suicidal thoughts; (3) task-based fMRI methods, with an emphasis on functional connectivity analyses; and (4) implementing mixed-effects modeling for intensive longitudinal data. These goals will be accomplished through mentorship meetings, workshops, conferences, and coursework with a committed interdisciplinary team. Complemented by support from a dedicated research environment at the University of Pittsburgh, this fellowship will accelerate the applicant’s trajectory toward becoming an independent researcher focused on using multimodal research to identify how individual neurobiology interacts with one’s social environment to create enduring risk for STB. Project Number: 1F31MH143521-01 | Fiscal Year: 2026 | NIH Institute/Center: National Institute of Mental Health (NIMH) | Principal Investigator: Carly Lenniger | Institution: UNIVERSITY OF PITTSBURGH AT PITTSBURGH, PITTSBURGH, PA | Award Amount: $49,538 | Activity Code: F31 | Study Section: Special Emphasis Panel[ZRG1 F02A-D (20)] View on NIH RePORTER: https://reporter.nih.gov/project-details/11318316