Neural correlates and candidate mechanisms of suicidal thoughts and behaviors in youth: A review of task-based fMRI studies

J Affect Disord. 2026 Jun 7:122091. doi: 10.1016/j.jad.2026.122091. Online ahead of print.

ABSTRACT

Suicidal thoughts and behaviors (STBs) increase sharply during late childhood and adolescence, yet the neurodevelopmental mechanisms conferring risk remain poorly characterized. Mechanistic models of suicide emphasize disruptions in emotion regulation, self-referential processing, reward sensitivity, and cognitive control, but task-based neuroimaging evidence supporting these frameworks has not been systematically consolidated. This scoping review synthesizes task-based functional magnetic resonance imaging (fMRI) studies of STBs in youth to evaluate neural correlates and candidate mechanisms associated with suicidal ideation and attempts, following PRISMA guidelines for 18 studies (N = 9902; ages 9-20 years). Across neurocognitive domains (emotion regulation, self-referential processing, reward sensitivity, cognitive control), findings implicate distributed circuit-level dysfunction rather than focal deficits. Suicidal ideation was most strongly associated with inefficient or context-dependent recruitment of prefrontal control and self-referential networks, whereas suicide attempt history was linked to broader and more stable disruptions in salience, limbic, and action-oriented systems. Altered social and reward processing further suggest heightened sensitivity to rejection and reduced responsiveness to positive outcomes. Effects were most evident in clinically severe samples and largely absent in younger community cohorts, indicating that neural alterations scale with symptom severity and developmental stage. Importantly, patterns diverged between ideation and attempts, suggesting partially distinct neurocognitive pathways that may differentiate risk for thinking about suicide from progressing to suicidal behavior. Overall, current evidence supports models of youth suicidality as emerging from inefficient regulation and motivational systems that compromise adaptive responding under stress. Task-based fMRI may therefore help identify mechanism-targeted intervention points that distinguish ideation from attempts.

PMID:42259486 | DOI:10.1016/j.jad.2026.122091