The Role of the Reward System in Suicidal Ideation and Behavior

Psychiatric hospitalizations are often shaped by diagnosis and self-reported symptoms, but these approaches do not always capture the underlying patterns that influence recovery or forecast how long someone will be hospitalized. Suicidal ideation is one area where this gap becomes especially important. While it is a central factor in determining level of care, it is often treated as a single, uniform experience. In reality, two individuals may both report frequent or severe suicidal thoughts, yet differ in ways that matter for treatment (e.g., whether those thoughts are longstanding or more recent; how much they interfere with daily functioning; or how they relate to broader difficulties like emotion regulation or disability in work, social, or cognitive domains). These differences can shape how someone responds to care and how long they may need to remain in a hospital setting, but they are not always visible through diagnosis alone.

With their AFSP-funded grant, Dr. Ramiro Salas and his team studied 455 adult psychiatric inpatients, combining clinical assessments, which included detailed measures of suicidal ideation, with brain imaging data to test for groups of patients based on shared patterns rather than diagnosis alone. The imaging focused on structural connectivity, or how different regions of the brain are physically connected through white matter pathways that support communication across systems involved in emotion, thinking, and behavior.

The team identified 23 distinct patient profiles, each associated with different lengths of hospital stay. Of these 23 groups, only two showed similarly high levels of suicidal ideation but differed in their underlying brain connectivity: one linked to the cingulum–cingulate gyrus, which plays a role in emotional processing and regulation, and another to the corticospinal tract, a pathway involved in movement and the coordination of voluntary action. Both groups were associated with longer hospitalizations, suggesting greater clinical complexity. The findings also showed that functional disability (i.e., how much symptoms disrupt daily life) was a strong predictor of extended stay, highlighting how suicidal ideation may be better understood within broader patterns that shape treatment needs and recovery.

Citation: Toranzo, J. M., Zwir, I., Poblete, G. F., Fernández, F. J. A., Teixeira, A. L., Salas, R., & de Erausquin, G. A. (2025). Structural Connectivity and Clinical Features Allow Classification and Outcome Predictions in Psychiatric Inpatients. Neuropsychiatry (London), 15(2), 2, https://www.researchgate.net/publication/399624498_Structural_Connectivity_and_Clinical_Features_Allow_Classification_and_Outcome_Predictions_in_Psychiatric_Inpatients