What Causes Schizophrenia?
Schizophrenia is a serious disorder which affects how a person thinks, acts and feels. It is best described as a mental disorder which is characterized by abnormal social behavior and failure to understand what is real.
An individual suffering from Schizophrenia has common symptoms where they regularly hallucinate. It is also not uncommon for those with this disorder to have false beliefs that the people around them are continuously planning to attack or harm them. The two main regions of the brain that are involved in schizophrenia are both the hippocampus and the prefrontal cortex. The prefrontal cortex is involved in working memory, paying attention, staying focused, and organizing our thoughts. Individuals who suffer from this disorder have dysfunction in this particular area of the brain. Secondly, individuals who are schizophrenic often have smaller hippocampi. This affects both the memory and learning of the patient and can result in some of the disorganized thinking that is seen in cases of schizophrenia.
The signs and symptoms of schizophrenia are pretty unique to humans, or at least they’re hard to imagine or notice in animals like mice or rats. One clue is that the majority of antipsychotic medications that improve schizophrenia symptoms block the Dopamine receptor D2, which reduces dopamine levels in neurons. This suggests that the condition has something to do with increased levels of dopamine. These medications, however, are neither universally nor completely effective. They do not work for everyone with schizophrenia, which adds to the confusion and means there is probably more to it than just the D2 receptors. Interestingly, one of the most effective antipsychotic drugs ‘Clozapine’ is a weak D2 antagonist, which suggests that other neurotransmitter systems like norepinephrine, serotonin, and GABA are involved.
Twin studies have shown support for a genetic basis as well, even though there haven’t been any specific genes conclusively linked to schizophrenia yet. Also, environmental factors, like early or prenatal exposure to infection, and certain autoimmune disorders like celiac disease have been linked with schizophrenia. Another important set of clues involves the epidemiology. Schizophrenia seems to happen slightly more in men than women. Onset of the condition is often in the mid-twenties for men but late-twenties for women; and the clinical signs of schizophrenia are often less severe. Some studies suggest this difference might be due to an estrogen regulation of dopamine systems. There doesn’t, however, seem to be any differences among race.
Dopamine Hypothesis of Schizophrenia
The dopamine hypothesis proposes that schizophrenia involves an excess of dopamine activity. One of the reasons this hypothesis came about was from the observation of people who overdose on certain major stimulants, such as cocaine and methamphetamine. These individuals have similar behaviors and cognitions as those individuals with schizophrenia. Indeed, physicians have reported that it is difficult upon initial observation to determine whether somebody is schizophrenic, or whether they are experiencing an overdose from a major stimulant. Another factor that supports the idea of the dopamine hypothesis, in regards to this disorder, was that drugs that block dopamine appear to be effective in treating the positive symptoms present in schizophrenia.
Another neural transmitter that does seem to play a role in schizophrenia is Glutamate. It appears that deficiencies of Glutamate may also be an explanation for the symptoms found in schizophrenia. That is, Glutamate is important for memory, learning, neural processing, and the development of the brain. It also allows us to make some stimuli more important than others. Therefore, glutamate is crucial to selective attention, such as focusing attention on some items of information while ignoring others. It may also explain why patients who are suffering from this disorder have trouble with cognitive control, sustained attention, and working memory.
Epigenetic Factors for Schizophrenia
In spite of the fact that genetic factors play a large role in the development of schizophrenia, simply possessing a genetic predisposition does not mean that someone is going to develop the disorder. However, research studies have shown that children who are exposed to neglect and abuse early in life are more likely to have schizophrenia later in their life. An individual can possess a genetic predisposition and still go throughout their lives without ever developing the disorder. It is also possible that they can possess the genetic predisposition, be exposed to an environmental event, and then develop the disorder as a result.
Just as drugs can serve as epigenetic agents, neglect and abuse can also serve as epigenetic agents. These agents are responsible for the onset of this disorder.
Risk Factors for Schizophrenia
The more closely a person is related to someone who suffers from schizophrenia, the more likely that person is also to suffer from the disorder. So, we know from this that there is a genetic component to schizophrenia, however, this is not enough on its own. There also needs to be some type of stressful environmental experiences that the individual suffers from. These two things together are really what are required and we refer to this as the diathesis stress model. Diathesis means the biological predisposition, while the stress means a certain type of environmental event. One of the risk factors that is involved, environmentally, in the potential development of schizophrenia is maternal infection. This means that if a pregnant woman is exposed to diseases or infections, her baby, later on in life, actually has an increased risk of having schizophrenia. Some of the infections and diseases include influenza, herpes, toxoplasmosis, and rubella. Toxoplasmosis is found in feline feces, which is one reason why doctors always recommend that pregnant women stay away from cat litter. Other environmental risk factors include chronic stress and taking certain drugs.
By default, these environmental risk factor don’t cause or even increase schizophrenia. It is when they are combined with a genetic predisposition that it can lead to schizophrenia. It is for this reason why it is best advised for any individual to stay away from drug consumption, and opt for regular health checkups and doctor’s appointments.
The Bottom Line
Because of the severity of the symptoms associated with schizophrenia, there has been a great deal of research to look at the causes for this disorder. While the best solution of curing Schizophrenia lies in preparing yourself to have a calm temperament, another solution lies in indulging in meditation. From various researches based on the disorder, we can clearly conclude that schizophrenia is both a fascinating yet tragic disorder. Schizophrenia is a result of the dynamic interplay between both nature and nurture.
