Dissociable impairments of verbal learning differentiate childhood risk profiles for schizophrenia

Elsevier, Schizophrenia Research: Cognition, Volume 28, June 2022, article 100239/
Authors: 
Emma J. Carpendale, Alexis E. Cullen, Hannah Dickson, Kristin R. Laurens

Poor verbal learning and memory function is well-documented among individuals with schizophrenia and those at clinical high-risk for psychosis. This study aimed to identify these impairments among children aged 9–12 years with different schizophrenia risk profiles (family history or antecedents of schizophrenia, each of higher[H] or lower[L] risk load) relative to typically developing peers. These three groups were recruited via community-screening, and differentiated for analysis into: typically developing children (TD = 45); children who had 1 first- or ≥2 second-degree affected relatives (FHxH = 16) or one second-degree relative (FHxL = 15); and children presenting multiple replicated antecedents of schizophrenia whose clinical symptoms persisted at 2- and/or 4-year follow-up (ASzH = 16) or remitted during follow-up (ASzL = 16). Verbal learning/memory measures assessed at baseline (age 9–12 years) included: (i) total recall; (ii) trial 1 recall; (iii) learning score; (iv) intrusions; (v) total words lost; and (vi) serial position patterns. Analyses of variance indicated that FHxH and ASzH youth demonstrated impaired total recall compared to TD and ASzL children and lost significantly more words between trials than TD and FHxL children. Learning score was impaired among both FHxH and FHxL relative to TD and ASzL children. Thus, among putatively at-risk children, total words recalled and lost distinguished those with higher risk load (by family history or persistent antecedent symptomology), whereas learning score indexed familial vulnerability. Follow-up of the sample is needed to determine the capacity of verbal learning deficits to predict later illness and provide a potential avenue for early remediation to improve clinical or functional outcomes.