The inferior parietal lobule is associated with suicidal outcomes in adolescents and youths with non-suicidal self-injury.
Authors
Affiliations (4)
Affiliations (4)
- Peking University HuiLongGuan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China.
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.
- Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
- Peking University HuiLongGuan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China. Electronic address: [email protected].
Abstract
Non-suicidal self-injury (NSSI) is a leading predictor of suicidal thoughts and behaviors in adolescents and youths, yet the neurobiological mechanisms underlying this transition remain unclear. The Integrated Motivational-Volitional (IMV) model links NSSI to suicidal outcomes, but its phases have rarely informed neuroimaging work. We examined 173 adolescents and youths (117 NSSI, 56 non-NSSI) recruited from a psychiatric hospital who underwent structural MRI. Nine theory-driven regions of interest (ROIs) informed by IMV phases were analyzed using ANCOVA, bootstrap mediation, sequential path analysis, and machine-learning classification. Sensitivity analyses controlled for borderline personality disorder, depression, anxiety, image quality, and age range. Four ROIs showed significant group differences after false discovery rate (FDR) correction: transverse temporal gyrus, putamen, posterior corpus callosum, and inferior parietal lobule (IPL). Only IPL thickness showed an FDR-corrected indirect association with suicidal ideation through NSSI frequency (behavior-frequency composite score); its group difference was modest, whereas transverse temporal thickness was the most robust across sensitivity analyses. In an exploratory path model informed by the IMV framework (IPL thickness → NSSI frequency → suicidal ideation → suicide attempts), the serial indirect effect was significant; anxiety and depression were each associated with the IPL-NSSI link. Exploratory machine learning classified NSSI at modest accuracy but not suicidal outcomes. This study provides preliminary IMV-informed structural neuroimaging findings in adolescents and youths. The IPL emerges as a candidate neural correlate associated with suicidal outcomes through affective symptoms, NSSI, and ideation. Brain features classify NSSI but not suicidality outcomes.