Conceptual Models of Schizophrenia

Overview

Models of schizophrenia are based on a philosophical and historical background (analytical, exis-tentional, sociological and antipsychiatric) and from actual scientific findings.Genetic model - the hypothesis of heredity of schizophrenia monogenetic or polygenetic (multifac-torial) was neither confirmed nor ruled out.Model of an extrauterine timed error - developmental - assumes discontinuation of dopamineafferentation into cortex (—early silenceie).Cognitive - behavioural model - incapacity to respond to external stimuli, creates different neuralmaps in the brain with a negative impact on the developmental prognosis of the child.Infectious model - activation of endogenous retrovirus leads to cellular disorganization.Neurotransmitted model and morphological changes - assumes dopamine hyperactivity (in limbicsystem and basal ganglia), hypoactivity in mesocortex and in prefrontal area).The author describes changes of serotonin, muscarine and gabaergic neurotransmission. Reducti-on of gaba receptors is associated with cognitive deterioration, psychotic symptoms and in rareinstances with catatonic manifestations. The binding characteristics of receptors and their occu-pancy determine the antipsychotic effect and incidence of extrapyramidal symptoms of neurolep-tics. Examination by imaging methods (computed tomography, magnetic resonance, positronemission tomography, single-photon emission computed tomography and magnetic resonancespectroscopy) reveals ventriculomegaly, reduction of gray matter in the frontal and temporallobe, reduction of the amygdalohippocampal complex and in some studies also diminution of thecerebellum. Despite all these great achievements made possible by imaging methods and studiesof the human genome we still do not know why 90% of people do not develop schizophrenia.

Key words:
schizophrenia models (analytical, existentional, sociological, antipsychiatric, genetic,extrauterine timed errors, cognitive behavioural, infectious, neurotransmission).