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The neurodevelopmental hypothesis
The neurodevelopmental hypothesis suggested
that schizophrenia in which the pathological changes of the disorder are laid down early in life, presumably through genetic influences, and then modified by maturational and environmental factors (Murray et al, weinberger 1987).
M.Bleuler- 4A symptoms：

Association disorder Apathy Ambivalence Autism
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History（3）
Schneider：first rank symptoms
1.Thought hearing 2. Third-person hallucinations 3. Hallucinations in the form of a commentary 4. Thought withdrawal or insertion 5. Thought broadcasting /diffusion 6. Forced feeling 7. Forced impulsive 8. Forced behavior 9. Somatic passivity experience 10. Delusional perception
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Part 2 Etiology
Biological factors
1．genetics 2．The neurodevelopmental hypothesis 3．Changes in brain structure 4．Biochemical abnormalities
Personality factors Psycho-social factors
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Genetics (4)
The results of adoption studies
The
rate for Schizophrenia is greater among the biological relatives of the Schizophrenia Adoptees than among the relatives of control. The finding supports the genetic hypothesis.
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Outcome evaluation(multi-dimensions)

Clinical outcome Social function Quality of life Living condition Family condition others
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History（1）
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Some findings compatible with the neurodevelopment hypothesis of schizophrenia



Non-progressive structural brain lesions Non-progressive cognitive impairment Cytoarchitectural disturbances without gliosis Cognitive and social impairments in childhood ‘Soft’ neurological signs Excess of winter births
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Epidemiology( 3)


Age：the age of onset in 50% of patients is 20~30 year old，over 80% of patients is 16~35year old. Gender： Schizophrenia occurs equally in men and women(in abroad) The prevalence in men is more than women (1.6:1) in China. The mean age of onset is about 2 to 5 years earlier in men than women.
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Part one
Introduction
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The definition of Schizophrenia in CCMD-3
Schizophrenia comprises a group of psychotic disorders of unknown specific etiology often presented with a gradual onset of abnormalities in perception, thought, motion and behavior since young adulthood. Consciousness is usually maintained. Intelligence is intact, but in some cases, there is some degree of cognitive impairment. The natural course of the disorder is chronic remitting but sometimes deteriorating.
1. Demence precoce(Morel,1857) 2. Hebephrenia(Hecker,1871) 3. Catatonia(Kzhlbaum,1874) 4. Kraepelin(1896)thought all above descriptions are different types of the same disease-dementia praecox
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Genetics (3)
The results of twin studies concordance rates among MZ pairs is higher than that among control(35-60 times) concordance rates are about 50% for MZ and about 10% for DZ. It might be expected that some environmental factors relevant to etiology. The risk of schizophrenia in the offspring of an unaffected twin is the same as that of an affected twin.
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Epidemiology (1)
Prevalence ： Point prevalence in China (1982): 4.75‰（rural area 3.42‰，urban 6.06 ‰ )。 Total prevalence in China(1982):5.69‰，(6.55 ‰ 1999)。 Lifetime prevalence in USA（1988）13‰。
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Molecular genetic studies
Two main approaches: 1. linkage analysis It is applied to multiply affected families, but no linkage markers have been clearly identified. 2. Candidate gene approaches Genes for biological mechanisms that may be involved in Schizophrenia have been localized and cloned. Using this technique, a number of genes coding for DA and 5-HT receptors have been excluded from linkage to Schizophrenia in various pedigrees.
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Genetics (1)
Studies Method: Family studies Twin studies Adoption studies
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Genetics (2)
The results of family studies The risk of Schizophrenia. Schizoaffective disorder, and schizotypal personality is increased in firstdegree relatives of patients with Schizophrenia. The risk of both Schizophrenia and mood disorder is increased in first-degree relatives of patients with schizoaffective disorder. The risk of bipolar illness is not increased in firstdegree relatives of patients with schizophrenia.
精神病学
Schizophrenia and Other Psychotic Disorders
L分裂症的临床表现、诊断和鉴别诊断、 治疗和预防复发策略 2．了解精神分裂症疾病的分型、预后特征 3．了解精神分裂症疾病的病因学 4. 了解其它精神病性障碍的概念