Cognitive impairments are considered a component of the extended clinical syndrome of schizophrenia. the aim of the current project was to investigate putative cognitive deficits in individuals with Early Onset Schizophrenia (EOS; defined herein as onset before the age of 18) and their relatives.

53 EOS probands and 117 unaffected first-degree-relatives were examined on memory (Wechsler Memory Scale-Revised), verbal learning and recognition (California Verbal Learning Test), and attention (SPAN of apprehension test and degraded-stimulus continuous performance test (DS-CPT)). the Structured Clinical Interview for DSM-IV yielded four diagnostic groups: EOS probands; relatives with Mood Disorders; other Axis I diagnoses; and no diagnosis (healthy). Analysis of co-variance was performed with diagnosis as fixed factor and age as covariate.

EOS probands under performed on General Memory, Verbal Memory and Delayed Recall indices (WMS-R) compared to their relatives. both EOS and relatives with a mood disorder performed less well on Visual memory and Attention/Concentration indices [p< 0.001]. Relatives without Axis I diagnosis differentiated from EOS on all indices [p< 0.01]. Verbal learning and recognition impairments segregated in EOS and differentiated patients from their relatives. EOS probands and relatives with an Axis I diagnoses showed rapid visual information processing impairments (SPAN) compared to healthy relatives, while sustained attention (DS-CPT) remained relatively preserved in EOS and relatives.

Genetic predisposition to schizophrenia may be mediated by visual information processing impairments, which differentiates healthy relatives from relatives with an Axis I diagnosis. Sustained attention seems to be a selective strength in EOS and relatives.