Anomalous self-experience in substance-induced and primary psychotic disorders: a cross-sectional comparative study using the EASE interview.
Annals of general psychiatry November 25, 2025 Luisa De Risio, Alessio Mosca, Arianna Pasino et al.
Anomalous self-experiences (ASEs), disturbances in the sense of a minimal self, are considered a core feature of primary psychotic disorders (PPDs) like schizophrenia, but it was unclear whether they also occur in substance-induced psychosis (SIP). This study compared ASEs in 27 clinically stable patients with schizophrenia spectrum disorders (SSD, mean age ~27) and 27 with SIP (mean age ~28) using the EASE interview. Total ASE scores did not differ between groups. However, SIP patients showed significantly higher disturbances in self-world boundary (Domain 4), while SSD patients trended higher in self-awareness and presence (Domain 2) and existential reorientation (Domain 5). These findings suggest ASEs are not exclusive to primary psychoses and challenge the assumption that self-disorders are unique to endogenous psychosis.