Impaired Corollary Discharge Mechanisms in Schizophrenia: Evidence From Readiness Potential and Auditory N1 Suppression
AI Summary
Schizophrenia patients lacked the readiness potential increase during vocalisation seen in healthy controls, indicating altered pre-movement cortical activity.
Healthy controls showed coupling between RP increase and auditory N1 suppression; this relationship was absent in patients, indicating impaired CD mechanisms.
Reduced N1 suppression in patients correlated with higher IPASE scores, linking CD deficits to anomalous self-experiences and impaired sensory prediction.
BACKGROUND AND HYPOTHESIS: Altered brain activity preceding behavior may reflect a reduced ability to suppress the sensory consequences of self-generated actions in schizophrenia. The corollary discharge (CD) mechanism has been proposed to underlie this process. In the present study, we investigated CD by analyzing the readiness potential (RP) and its relationship to auditory N1 suppression in patients with schizophrenia compared to healthy controls (HCs). We also examined the association between RP activity and anomalous self-experiences (ASEs).
STUDY DESIGN: Event-related potentials were recorded from 48 patients with schizophrenia and 55 HCs during a vocalization paradigm including talk and listen conditions. RP amplitude and N1 suppression were quantified as the amplitude difference between listen and talk conditions. Regression analyses assessed the relationship between these components within each group and examined associations between RP and N1 amplitudes and ASEs, measured using the Inventory of Psychotic-Like Anomalous Self-Experiences (IPASE) scale, in the schizophrenia group.
STUDY RESULTS: In the talk condition, HCs showed greater RP amplitude compared with the listen condition, a difference that was absent in the schizophrenia group. In HCs, this RP increase was followed by suppression of the N1 component. A significant correlation between RP amplitude and N1 suppression was observed in HCs but not in patients. Importantly, reduced N1 suppression in patients with schizophrenia was associated with higher IPASE scores.
CONCLUSIONS: These findings suggest that schizophrenia involves impairments in early cortical processes related to efference copy and corollary discharge mechanisms, reflected in reduced RP amplitude and the lack of coupling with N1 suppression. Such alterations may contribute to deficits in sensory prediction and to anomalous self-experiences in schizophrenia.
Schizophr Bull. 2026 Apr 10;52(3):sbag064. doi: 10.1093/schbul/sbag064.ABSTRACTBACKGROUND AND HYPOTHESIS: Individuals with schizophrenia report that time can feel discontinuous. Difficulties in benefiting from the passage of...
Schizophr Bull. 2026 Apr 10;52(3):sbag068. doi: 10.1093/schbul/sbag068.ABSTRACTSTUDY DESIGN: In this secondary analysis of a randomized controlled trial, individuals aged 18-65 with a psychotic disorder and...
Schizophr Bull. 2026 Apr 10;52(3):sbag048. doi: 10.1093/schbul/sbag048.ABSTRACTBACKGROUND: According to predictive processing models, hallucinations can arise from over-weighting of prior expectations relative to sensory input. Individuals...
Schizophr Bull. 2026 Apr 10;52(3):sbag062. doi: 10.1093/schbul/sbag062.ABSTRACTBACKGROUND AND HYPOTHESIS: Persistent negative symptoms (PNS) often emerge early in the course of schizophrenia spectrum disorders, significantly impair...
Schizophr Bull. 2026 Apr 10;52(3):sbag067. doi: 10.1093/schbul/sbag067.ABSTRACTBACKGROUND: People with severe mental illness (SMI) are at an increased risk of infection mortality compared to the general...
Schizophr Bull. 2026 Apr 10;52(3):sbag049. doi: 10.1093/schbul/sbag049.ABSTRACTBACKGROUND AND HYPOTHESIS: The early phase of psychosis is critical for interventions to modify long-term outcomes. It is unclear...
