Efficacy of Personalizing Cognitive Remediation for Schizophrenia by Targeting Impairments in Early Auditory Processing

Early auditory processing (EAP) deficits are common but not universal in schizophrenia, are linked to impairments in higher cognitive functions and when improved are associated with downstream cognitive improvements. Assessment of baseline EAP training need provides an opportunity for cognitive remediation (CR) programs to personalize treatment and optimize impact. This confirmatory efficacy study examined the differential benefit of EAP training for those with and without baseline EAP deficits. Hypotheses were: (1) Only EAP impaired (EAP-) patients would benefit more from CR that included EAP training, (2) cognitive gains made by EAP- patients during CR that included EAP training would mediate the relationship between gains in EAP and functional capacity.

184 outpatient adults diagnosed with schizophrenia were classified as having intact (n = 91) or impaired (n = 81) EAP and randomized to CR with restorative exercise plans that either included EAP training (n = 89) or did not (n = 83). Cognitive and functional outcomes were measured post-treatment and 3 months later.

Across CR treatment conditions, cognitive gain effect size was moderate. Treatment condition did not significantly impact EAP, cognitive, or functional outcomes for either EAP group at final endpoint. EAP improved significantly but modestly for EAP- patients across conditions. Cognitive gains did not mediate the relationship between EAP gains and functional capacity.

These findings support the value of CR for people with schizophrenia, demonstrate that EAP deficits are malleable, and that cognitive and functional gains can occur for EAP impaired patients, regardless of whether EAP training is provided.