A serial mediation pathway linking parental socioeconomic status, cerebellar connectivity, verbal cognition, and alogia in psychosis

Both socioeconomic status (SES) disadvantage and cerebellar dysconnectivity are crucial contributors to cognitive deficits in schizophrenia. Our recent work has revealed a mechanistic pathway in which verbal ability fully mediates cerebellar-frontoparietal connectivity and alogia severity. However, how this pathway is upstream influenced by demographic risk such as parental SES is unclear. This study investigated 100 patients and 49 healthy controls drawn from the Human Connectome Project for Early Psychosis (HCP-EP) dataset. Effects of parental SES on cerebellar connectivity and verbal ability were estimated in patients and controls with linear regression models. A serial mediation pathway linking parental SES, cerebellar connectivity, verbal ability, and alogia severity was examined with structural equation modeling. We observed significant group by SES interaction on cerebellar connectivity ( p = 0.003) and borderline interaction effect on verbal ability ( p = 0.055). Both cerebellar connectivity and verbal ability were significantly associated with parental SES in patients ( p < 0.001) but not in healthy controls. Moreover, a significant serial mediation effect was detected involving cerebellar connectivity and verbal ability as key intermediate mechanisms bridging parental SES and alogia (i.e., SES -> cerebellum -> verbal ability -> alogia, p = 0.008). These findings support a potential sequential mechanism linking parental SES, cerebellar connectivity, verbal cognition, and negative symptoms in patients with psychosis. They also highlight a hierarchical pathway in which demographic risk may give rise to psychopathology through its impacts on brain organization and downstream cognitive processes.