- Mental Health
The Psychosis of Schizophrenia: Causes and Treatment
The Psychosis of Schizophrenia
3. The Psychosis of Schizophrenia: Causes and Treatment
Analysis of brain functioning of people with schizophrenia with Positron Emission Tomography (PET) has shown that a lowered frontal lobe activation of the brain during a working memory task poses the risk of increased activity of a neurotransmitter called “dopamine” in the synaptic junctions where neurons meet. Besides frontal lobes, functional differences in the brain activity of the schizophrenics also occur in the hippocampus and temporal lobes. Similarly, MRI (Magnetic Resonance Imaging) and other imaging technologies have shown clear differences in the brain activity of schizophrenics.
The brains of people with schizophrenia also look different than those of healthy people. MRI studies have shown that the volume of the whole brain and the hippocampus region are markedly reduced in schizophrenics, while the fluid-filled cavities at the center of the brain, called ventricles, are larger in schizophrenics as compared to healthy people.
Causes of Schizophrenia
Besides being genetically inherited, schizophrenia is also found to be triggered by some traumatic experiences during early adult life. It is now known that prenatal exposure to infections increases the risk of developing schizophrenia later in life. Besides, childhood experiences of abuse or trauma are also considered as serious risk factors for developing schizophrenia. Unsupportive parenting where children develop strained relationships with parents also contributes to an increased risk of developing this severe psychiatric disorder.
Certainly, there occur discrete biochemical changes in the brain cells or neurons of the victims that result in altered neurochemistry which is the hallmark of disintegrated thought process. The network of neurons that is spread all over the human body basically comprises billions of interconnecting neurons that pass on the neural message from one cell to the other in the form of specific neuro-chemical signals, which are nothing but biochemical modules called neurotransmitters. These substances allow brain cells to communicate with each other, and are released in very precise amounts at the junction points where the dendrites of one neuron intersect with axon terminals of another neuron. One such neurotransmitter known as “dopamine” plays a crucial role in brain chemistry. It is the excessive production of dopamine that disturbs the flow of information through the neural wiring, and thus wreaks havoc in thought process, typical in schizophrenia.
Many different genes seem to be involved in the abnormally raised activity of dopamine in the neurons. Certain genes linked to an increased risk of schizophrenia have been found, which produce defective proteins that play an important role in altering the neural signaling. Rare deletions or duplications of tiny DNA sequences in these genes make them alter their expression, thus causing the production of a defective variant of the normal protein. It is understood today that there is an increased production of dopamine receptor D2, also known as D2R, which is a protein encoded by the DRD2 gene. This is known to give rise to the positive symptoms of schizophrenia. Therefore, most of the antipsychotic drugs cause the D2 blockage or have dopamine blocking effect. However, newer antipsychotic drugs also affect the production of another neurotransmitter called serotonin. These drugs are commonly known as SSRI (Selective Serotonin Reuptake Inhibitor).
Persons at high-risk of developing schizophrenia include those having a family history of schizophrenia and undergoing some psychotic experience. Psychological treatments and medication seem to be effective in reducing the chances of such high-risk people to develop full-blown schizophrenia.
Treatment of Schizophrenia
Special class of medications known as antipsychotic drugs help in the treatment of schizophrenia, as they work by suppressing dopamine activity inside the neurons. In 1950 the drug “chlorpromazine” – the first drug developed with antipsychotic action – was synthesized. This drug indeed brought a revolutionary advancement in the treatment of schizophrenia, as hospitalization could be avoided and social rehabilitation of such persons could be done to a great extent. Chlorpromazine works on several receptors on neurons, blocking the activity of neurotransmitters that act by binding to those receptors. The side effects of this drug include sedation, constipation, hypotension and restlessness. Another drug group that blocks dopamine function is called “phenothiazines”, which can reduce psychotic symptoms.
Today, however, there are more effective antipsychotic drugs available in the market. Clozapine is the first atypical antipsychotic drugs used in the treatment of schizophrenia first introduced in Europe in 1971. Although a highly effective drug in the treatment of schizophrenia, clozapine unfortunately causes a drastic reduction in the number of the white blood cells, a condition called agranulocytosis, which can prove fatal. In 1989, the US FDA approved the use of clozapine for only in the treatment of resistant schizophrenia or to patients not responding to other antipsychotic drugs. However, periodic blood testing was made essential for patients taking clozapine to monitor the adverse effects of this drug on them.
Risperidone, first released in 1994, is also a common atypical antipsychotic drug used to treat schizophrenia. However, it induces weight gain and sexual dysfunction besides having other side effects common to most antipsychotic drugs. Similarly, another atypical antipsychotic drug, olanzapine is also associated with considerable weight gain and risk of metabolic syndrome.
Apart from medications, vocational and social rehabilitation are very important for making persons with schizophrenia lead a less traumatic life. Public education campaigns also assume great importance for reducing the burden of this disorder on human population, as information about risk factors and early symptoms of this mental disorder can help in timely treatment and social rehabilitation.
Personal counseling of the patient called psychotherapy is aimed at increasing the sense of their own well being. This involves several relationship building techniques like friendly communication and dialog for bringing about behavioral changes in the victims. Techniques like cognitive behavioral therapy and cognitive remediation help to treat psychotic symptoms, and improve social rehabilitation of people suffering from schizophrenia.