The treatment for schizophrenia prior to the 1950s was very limited and often involved harsh and ineffective methods.
Insulin-induced seizures (a) were a form of shock therapy used to treat schizophrenia in the early 1900s. The treatment involved injecting insulin into the patient, causing a coma and seizures, which was believed to alleviate symptoms of schizophrenia. However, the treatment was not effective, and it often caused significant harm to patients.
Restraint (b) was another method used to treat schizophrenia in the past. It involved physically restraining the patient to a bed or chair, sometimes for extended periods, as a means of controlling their behavior. This method was highly controversial and inhumane and is no longer used as a treatment for schizophrenia.
Phenothiazines (c) were one of the first effective medications used to treat schizophrenia in the 1950s. They are still used today and have been a significant advance in the treatment of schizophrenia.
Prefrontal lobotomy (d) was a surgical procedure used to treat schizophrenia in the past. The procedure involved removing parts of the prefrontal cortex of the brain, which was believed to alleviate symptoms of schizophrenia. However, this treatment was highly controversial and often had significant negative consequences for patients, including personality changes and reduced cognitive function. The procedure is no longer used as a treatment for schizophrenia.
Therefore, the correct answer to the question is (c) phenothiazines were not a treatment used for schizophrenia prior to 1956, as they were first introduced as an effective medication for schizophrenia in the 1950s.