Some remarks on etiological aspects of early-onset schizophrenia

Neurophysiological, neuropsychological, neuroanatomical, and neuroradiologi cal findings in schizophrenic psychoses demonstrate that subcortical (e.g., mesolimbic and diencephalic regions) as well as neocortical structures (e. g., dorsolateral prefrontal cortex, superior temporal and inferior parietal cortices) are involved. Special significance is accorded to the neuroanato mical connection between limbic structures and the dorsolateral prefrontal cortex. Here myelinization begins relatively late in humans, during the sec ond and third decade of life - a particularly vulnerable period for schizop hrenic onset. The nature of prepsychotic behavioral abnormalities in patien ts with early-onset schizophrenia as well as the existence of typical cogni tive dysfunctions preceding the manifestation of psychotic symptoms points to the importance of a dynamic imbalance of neocortical-subcortical interac tions in the etiology of schizophrenia. Based on the crucial importance of the prefrontal-hippocampal circuitry a stimulus barrier model of schizophre nic psychoses is elaborated, which integrates recent neurobiological findin gs as well as results of research in modern developmental psychology. One o f the implications of this model is the multidimensional treatment of schiz ophrenic patients.