Schizophrenia Neurodegenerative Model

Schizophrenia is a psychological disorder that involves hallucination, delusions, and depression.There has been a continuing debate regarding the nature of the illness. The first model, also the more longstanding and prevalent one, is the neurodevelopmental model of schizophrenia. It asserts that before onset, there are genetic and environmental factors that inhibit the normal development of neurons in the brain (Bloom 1993; Weinberger 1987). More recently, a neurodegenerative model was claimed.

Initially, there was less support of the degenerative model because there was a lack of technology to analyze brain matter and thereby studies that could document the loss of brain matter. But, once the capacity of non-invasive neuroimaging technology increased in the late 20th century, there was a boom in such studies. The degenerative model argues that over the course of illness, normal structures in the brain deteriorate (Davis 1999, Liberman 1999, Wyatt 1991). Conducting more research to look for the deterioration of the brain could make diagnosing schizophrenia more efficient.

Positive symptoms include hallucinations and hearing voices, while negative symptoms include depression and withdrawal. The disadvantage of this diagnostic method is that it makes the family and friends, of the subject, responsible. They must identify a problem and take the initiative to ask for help which results in a large number of unidentified schizophrenics who get worse (http://www.webmd.com/schizophrenia/guide/schizophrenia-tests).

Recently, enough data accumulated and created a promising method of diagnosis: anatomic pathology. A greater number of diverse studies have been implicating structural changes within the brains of chronic and first episode schizophrenics.As far back as 1992, Lieberman and colleagues concluded that there were higher overall rates of abnormal brain morphology in schizophrenics. Although chronic patients had higher abnormal morphology rates than first-episode patients, the differences were not statistically

And there is a potential to do just that, if the anatomic pathology of schizophrenia becomes linked to treatment response.

Neurobiological predictors of treatment response in schizophrenia have not been well defined because the lack of controlled trials with first episode schizophrenics (long term schizophrenics have been/are exposed to many other drugs which have confounding effects on the results).

In the present study we scanned a unique group of first-episode schizophrenia patients with little or no antipsychotic exposure enrolled in a double blind 12 week clinical trial of risperidone versus aripiprazole and age- and sex-matched healthy volunteers at baseline and following 12