“The underlying processes of episodic and autobiographical memories impairments in schizophrenia”

Abstract

I-ABSTRACT Schizophrenia is a severe psychiatric disorder marked by profound cognitive deficits, among which episodic memory (EM) and autobiographical memory (AM) impairments are particularly debilitating and linked to social functioning. This thesis investigates the underlying memory processes implicated in EM and AM dysfunction in schizophrenia. Two studies were conducted. Study 1 explored the roles of recollection and familiarity in relational and self-referential memory encoding in a healthy adult population (N=54) using a modified version of the RISE and an original Self-Referential Memory (SRM) paradigm. Recognition performance was assessed through receiver-operating characteristic (ROC) analyses. Results showed higher recognition accuracy for single item stimuli compared to paired items and demonstrated that familiarity—rather than recollection—supported the self-reference memory effect. Study 2 employed a quasi-experimental design to compare individuals with schizophrenia (n=27) to healthy controls (n=27), matched by age, sex, and socioeconomic status. Patients exhibited deficits in both recognition accuracy and dual-process parameters (familiarity and recollection), with impairments most pronounced under relational encoding demands. Notably, recollection—but not familiarity—supported self-referential memory in both groups. Across the combined sample, EM performance, particularly under self-referential encoding, predicted AM retrieval beyond the contribution of diagnostic status. These findings indicate that recollection and familiarity contribute differentially to self-referential memory across populations and suggest that impaired self-based encoding of episodic information may partially account for autobiographical memory dysfunction in schizophrenia. The results highlight cognitive mechanisms with direct relevance for targeted remediation strategies and psychotherapeutic interventions aiming to strengthen memory and personal identity in schizophrenia.