Cognitive Defect in Children and Adolescents with Schizophrenia Spectrum Disorders: Psychometric and Neuropsychological Approaches to the Assessment of Cognitive Disorders

The article is devoted to the diagnostic approaches of cognitive defects in schizophrenia using psychometric and neuropsychological methods. The clinical psychological research results of different kinds of cognitive defects in children and adolescents with schizophrenia spectrum disorders (74 subjects of average age of 11 ± 2 years old, 18 of which have passed a complete neuropsychological examination) are described. We have compared psychrometric and neuropsychological diagnostics results of children and adolescents with schizophrenia spectrum disorders with the results of reference group of children with normal development. The differences of intellectual levels depending on the diagnosis have been marked and the respective types of cognitive defect are described. The total (most severe) defect has been detected in children with progredient schizophrenia (F20). While in other groups (children and adolescents with non-progredient schizophrenia) there has been revealed partial defect. Complex psychometric and neuropsychological diagnostics allows to make more detailed evaluation of the cognitive defect and its structure. Neuropsychological diagnostics has also confirmed that there are intensity differences of brain dysfunction between the diagnosed groups. Patients with сhildren schizophrenia (F20) have notable dysfunctions (or functional immaturity) of cortical structures, while in the group of children with diagnosis of episodic schizophrenia (episodic with progressive clinical course) with progressive or stable defect (F20.x) impairment of interhemispheric coordination has been observed. Children and adolescents with schizotypal disorder (F21) have showed dysfunctions of subcortical structures. Our research results support the hypotheses about the interrelation between kinds of cognitive defect and specificity of neuropsychological status in children and adolescents with different kinds of progredient schizophrenia spectrum disorders.