الهام الجماس

Elham Aljammas

18/9/2013
Etiology of Mental disorders

Objectives:

1.to understand the relationship between different etiological factors
2.To analyze the possible &treatable causes.
3.To define the responsibility of the family & or the community .
4.To tackle the exact area in the treatment.

No single paradigm suffice =multifactorial

Some important etiological issues in psychiatry :
1.complexity of causes
2.classification of causes
3. concept of stress
4. concept of psychological reaction

In psychiatry the study of causation is complicated by 3 problems

1.lack of temporal association (childhood experience ,adult emotional disorder )
2.cause & effect
Parental deprivation in childhood & later antisocial behavior
3. indirect mechanism(genetic predisposition) may be mediated in part through psychological factors .

Models of aetiogical factors

1-Biological Model
2-Social Model
3-Psychological ModeL


Aetiological factors could be divided into :
1.Predisposing factors
Family history
Disturbed childhood

2.Precipitating factors:

Loss of jobs
Physical illness
Loss of loved one

3.Perpetuating factors

Biological Models

1 .Mental process are derived from operations of the brain ,resulting in behavioral disturbances.

2.Gene through their protein product ,have important effect on brain function & therefore exert a significant control over behavior.
3. social &behavioral effect exert their impact on the brain in part through changes in gene expression
Changes in gene expression & the consequent pattern of synaptic connectivity underlie the ability of experiences such as learning &psychotherapy to change behavior.

a.Monamine theories

f.Genetic:

Heritability estimates for for selected psychiatric disorders are :
Schizophrenia 80%
Major dep. 40%
Bipolar disorder 80%
Generalized A D 30%
Panic disorders 40%
Phobia 35%
Alcohol problems 60%

1-Family studies:.

60% of schizophrenic have no family history of the illness.
If one parent is schizophrenic 15% of offspring develop the illness .
If both parents are schizophrenic, 46% of them suffer
2-Twin studies
Mz twins have 42% concordance rate
Dz twins have 10% concordance
3.Adoption studies

Pychologicalmodel