QUESTION: What would a sibling of a person with schizophrenia function like? What are the traits of a schizophrenic family bind that I used to hear about?ANSWER: Because schizophrenia is a biological disease, siblings of people with schizophrenia are 10 times more likely to develop the disorder than other people; they are also at greater risk for schizophrenic spectrum disorders like schizotypal personality disorder and schizoaffective disorder. In other words, some siblings may have schizophrenia-like tendencies of their own, even if they don't have the full-blown disorder.
Double-bind theory is Gregory Bateman's 1950's-era proposition that what causes schizophrenia is repeated no-win dilemmas in the child's family life. In other words, the child was repeatedly confronted with statements that contained two contradictory statements (i.e. a double bind). Because of the child's attachment to the caregiver, he was eager to do as the caregiver asked -- the problem was that by meeting one demand, he would be defying the other. Because he was presented with such double binds on a regular basis, and because he doesn't have the cognitive maturity to know how to choose one statement over the other to escape the double bind, he eventually escapes from the extraordinary stress the double bind causes by retreating from the "real world" and into psychosis (i.e. delusions and hallucinations).
Double-bind theory has fallen out of favor with regards to schizophrenia for two reasons. First, we have so much data that demonstrates a biological cause for schizophrenia, not an environmental one (though typically the biological tendency is triggered by environmental stressors). Second, double-bind theory is nearly impossible to test, so there is little empirical research that can support it.
There is research, however, to support the idea that a problematic family environment can contribute to the relapse of someone who's been treated for schizophrenia. Most notably, people with schizophrenia are likely to relapse when their family is high in expressed emotion (EE). Expressed emotion consists of three parts: criticism, hostility, and emotional overinvolvement.
People with schizophrenia are extremely sensitive to stress, and being treated with constant dislike, disapproval, rejection, disrespect, and the assumption that they are not capable human beings is enough to stress anyone out!
So even if the siblings in your story don't have schizophrenic tendencies themselves, you could make them somewhat critical and hostile people who show a lot of expressed emotion toward their brother or sister!
Hope that's helpful!
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