Striatal circuit function is associated with prior self-harm in remitted major depression

- The neural mechanisms underlying risk of self-harm are incompletely understood.
- Striatal circuit function is associated with past self-harm in remitted depression.
- Previous studies have found a similar association during depressive episodes.
- Striatal circuits may play a key role in the neural mechanisms of suicide risk.

The neural processes underlying suicide risk are incompletely characterized. This project utilized functional MRI (fMRI) to determine whether a history of self-harm was associated with striatal circuit function in recurrent major depression in remission. Twenty unmedicated subjects with recurrent major depression and 21 controls were studied using fMRI and a motor activation paradigm. We used functional connectivity analyses to identify circuits with aberrant connectivity. We also used correlational analyses to determine whether functional connectivity was associated with a history of self-harm. There was a significant association between history of self-harm and functional connectivity of a striatal-motor circuit. Additionally, striatal and cortical midline circuits exhibited decreased functional connectivity in remitted unipolar depression as compared to controls. Our previous study of individuals experiencing an episode of depression indicated an association between striatal circuitry and a history of self-harm. That study, along with the results reported herein suggests striatal circuit function may play a key role in the neurobiology of suicide and self-harm risk in recurrent major depression. Our results also indicate that both striatal and CMS circuit dysfunction persists in the euthymic state of recurrent major depression and thus may represent trait pathology.