Abnormal connectivity in the fronto-striatal network in adolescent depression with psychotic symptoms

Adolescent depression patients with psychotic symptoms have a worse prognosis and higher risk of suicide compared to those without psychotic symptoms, however, the neurophysiological underlying pathway is still unclear. The fronto-striatal network (FSN) may play an important role in the association between depression and psychotic symptoms. This study aims to investigate the specific alterations of the FSN in adolescent patients with depression, both with and without psychotic symptoms, and determine whether it could serve as an underlying neuropathological underlying pathway contributing to clinical symptoms.

Based on the presence or absence of psychotic events such as hallucinations or delusions, adolescent depression patients were divided into a psychotic depression (PD) group (n = 32) and a non-psychotic depression (NPD) group (n = 41). All participants underwent comprehensive clinical assessments, including the Brief Psychiatric Rating Scale (BPRS) for general psychopathology and the Patient Health Questionnaire-9 (PHQ-9) for depressive symptom severity. Resting-state functional magnetic resonance imaging data were acquired using a 3.0T scanner. These data were preprocessed and analyzed using independent component analysis (ICA) to identify the FSN for subsequent between group comparisons and correlation analyses.

In contrast to NPD, PD group demonstrated decreased connectivity in the bilateral striatum (bilateral caudate and putamen) (cluster-based family-wise error 0.05 correction). Furthermore, a significantly negative correlation was observed between the left striatum and BPRS scores (r = - 0.385, P = 0.030) in PD group, while no correlation was found in NPD group. The mediation analysis results showed that no mediating effect of PHQ-9 scores was found in the left striatum and the BPRS scores of PD group, nor was any mediating effect of PHQ-9 scores in the right striatum and the BPRS scores of NPD group.

Our results indicate a distinct alteration in the function connectivity in the bilateral striatal between PD and NPD, providing insights into the potential pathogenesis of psychotic symptoms in adolescent depression.