Animal Models of Schizophrenia

Chung, Young Chul

Abstract

Animal models of schizophrenia and the mechanisms of symptom-formation based on the study of those were reviewed. Firstly, in the animal models of schizophrenia, there are three subtypes: genetic, homologous, and animal assay models. Homologous models are the ones that similar symptoms as with schizophrenia were reproduced in animals. Therefore, they can be used for the exploration of the mechanism of symptom-formation by manipulating various treatments and measuring consequent results. Animal assay models evaluate physiologic or behavioral processes which are already known to be important in a disorder. By observing the effects of new drugs on the processes, they can be used as a screening test for the potential utility of those. All the animal models, however, must be regarded as the ones for specific symptoms, mainly behavioral ones, not schizophrenia itself since the symptoms of affect and thought can hardly be assessed in animals. Secondly, as far the mechanisms of symptom-formation, dopaminergic dysfunction was mainly highlighted. Main theory is that hyperdopaminergic activity in the subcortex is likely to cause a filtering defect, transmitting sensory overloading to the cortex which in turn could cause(+) symptoms such as cognitive and perceptual fragmentations while hypodopaminergic activity in the prefrontal cortex is likely to cause cognitive dysfunctions such as impaired attention, delayed response, and poor working memory test. In the future, it is hoped that with the development of the more specific and sensitive animal models of schizophrenia, the more elaborate and comprehensive mechanisms of symptom-formation would be revealed.