Question

What is the vulnerability model of schizophrenia? How does it account for schizophrenia developing in an individuals with a low genetic predisposition? How does it account for schizophrenia NOT developing in some with a high genetic predisposition?

Answer 1

• In schizophrenia, vulnerability may include genetic predisposition, birthing complications, and CNS viral infections. Stressful life events (e.g. being fired from work, terminating a relationship, or moving to a foreign environment) and biological stressors (e.g. substance abuse) may exacerbate the illness by triggering the emergence or reoccurrence of symptoms. However, protective coping mechanisms may safeguard vulnerable persons by weakening or eliminating symptoms.
• Some people are biologically vulnerable to certain psychiatric disorders: bipolar disorder, major depression, schizophrenia etc.
• This vulnerability is determined early in life by a combination of factors, including genetics, prenatal nutrition and stress, birth complications, and early experiences in childhood (such as abuse or the loss of a parent). This is why some families are more likely to have members with a particular psychiatric disorder.
• With schizophrenia it is becoming increasingly evident that having the gene associated with schizophrenia is just a starting point. If you have the genes, but don't experience the environmental contributing factors or "triggers" for schizophrenia then evidence suggests that you'll never get schizophrenia. However, if you are exposed to certain environmental factors - then the chances seem to increase (and the more environmental factors a person experiences, the higher the risk) that the person will ultimately get schizophrenia.
• So even if the person has a high biological vulnerability but still if the environment they are living and brought up in is healthy they are less likely to develop schizophrenia.