Sunday, 2 June 2013

Schizophrenia Overview

I came across schizophrenia from the book: The Brain That Changes Itself and decided to investigate more. A quote from the book stood out in my mind; "Brain exercises may be as useful as drugs to treat diseases as severe as schizophrenia". So here's everything I found out anyway.

There are many sub-types of schizophrenia suggesting that it is not a single disease but rather made of many smaller components. In general schizophrenia can be considered a disease of cognitive abnormalities, consisting of abnormal sequential thought known as loose association. The average schizophrenia sufferer will struggle to understand metaphors and follow logical stories. Instead of going through a story and displaying it chronologically they may become distracted and veer off in seemingly random processes of thoughts. This can also be referred to as tangential thinking. It is common to become confused by multiple meanings of words and when talking about one topic or word they may divert between alternative meanings of terms without realising.

Common physiological differences between the average person and the average schizophrenia-sufferer are that the latter normally has a smaller brain and enlarged brain ventricles. Surprisingly, this does not mean that schizophrenics are all less intelligent than other individuals and studies suggest that they span the full range of IQ levels.

In brain scan studies where schizophrenics were given cognitive tests it was shown that they had abnormal brain activity in response to these tasks. One expert said: "Instead of activating very specific and focal regions that are necessary for that particular task, they don't activate the regions that they are supposed to activate and instead they activate other regions... indicating that there is something wrong in the network of the brain that is designed to deal with specific tasks and challenges in everyday life."
Symptoms of schizophrenia are divided into positive and negative categories. Positive symptoms describe those symptoms which reflect an excess or distortion of normal functions, whereas negative symptoms reflect an absence of normal functioning.

The positive symptoms are:

- Hallucinations - auditory hallucinations are a common sign of schizophrenia (hearing voices)

- Delusions

- Disorganised speech

Negative symptoms are:

- Lack of will

- Social withdrawal

- Loss of speech

- Loss of pleasure

Despite what some may think, statistically, schizophrenics are less dangerous than 'normal' individuals in society. The rates of violent crime committed by schizophrenics are extremely low but, they are more prone to cause themselves harm.

As schizophrenics get older, positive symptoms tend to alleviate and negative symptoms become more pronounced.

Schizophrenia is normally diagnosed between the ages of 18 to 30. This may due to the maturation of the frontal cortex which usually receives a massive boost in maturity between ages 18-25. If you make it to age 30 without developing symptoms of schizophrenia then it is highly unlikely that you will ever have it. Normally, the symptoms are brought on by major stressors such as environment change or bereavement. Roughly 1-2% of the general population become schizophrenic in their lifetime.

There are a number of ideas as to what causes schizophrenia. Three ideas that are based on different neurotransmitters have come to my attention.

Firstly, serotonin. Serotonin is similar in structure to many strong hallucinogens and these hallucinogens fit into serotonin receptors. Having an excess of serotonin would explain why schizophrenics experience auditory and visual hallucinations.

Secondly, glutamate. Whenever people take the drug PCP they begin experiencing thoughts and sensations such as feeling detached from their environment which is quite common in schizophrenics. PCP works by wildly stimulating a certain type of glutamate receptor.

Lastly, and more widely researched, Dopamine.The dopamine hypothesis is that somewhere in the brain of a schizophrenic there is an excess of dopamine in the synapses. This is supported by elevated levels of breakdown products associated with dopamine being present in the blood, urine and cerebrospinal fluid. Also, all of the classic drugs that work with schizophrenia block dopamine receptors. Generally, if you give a schizophrenic a drug that reduces the activity of dopamine receptors, their symptoms alleviate. Autopsies too, have shown that there are greater amounts of dopamine receptors in the frontal cortex of these patients. However, some anti-psychotic drugs increase dopamine signalling with alleviation of symptoms.

Examples of abnormalities relating to the brain:

- Whenever a person with schizophrenia is hallucinating there is an extremely high level of metabolic rate throughout the brain.

- When performing memory tasks hippocampal metabolism does not increase as much as a healthy individual.

- Due to enlargement of the brain ventricles the amount of available space for the brain to grow is reduced and this results in contraction of the cortex, particularly in the frontal cortex.

- The thalamus tends to be atrophied (smaller / shrunken).

- There is a reduction of a protein called reelin, a protein involved in cortical maturation. This may indicate that schizophrenics' brains don't mature fully in late adolescence / early adulthood.

- Finally, in studies of the frontal cortex some studies have shown that there are fewer neurons or fewer glia or fewer of both in comparison to healthy individuals.

Stages of Schizophrenia

1) Prodrome:

- Suspiciousness, unusual thoughts, unrealistic beliefs of abilities - grandiosity

- Changes in sensory experience (hearing, seeing, feeling, tasting or smelling things that others don't experience)

- Disorganized communication (difficulty getting to the point, rambling, illogical reasoning)

35% of individuals presenting one of these symptoms develop psychosis within 2.5 years. Substance use including alcohol and marijuana increase the risk of developing psychosis.

Prodrome can last for up to 3 years and is the perfect time to intervene.

2) Active phase:

- Delusions

- Hallucinations

- Noticeable differences in thinking, behaviour and feelings.

During a lifetime some people suffering from schizophrenia may become actively ill once or twice or many times.

3) Residual phase:

After the active phase, people with schizophrenia may be weary, unmotivated, have trouble concentrating and withdraw from other people. This phase is similar to the prodrome phase. Unfortunately effects of the residual phase may increase with each occurrence. The best thing to do therefore, is attempt to avoid a relapse into the active phase.

People with schizophrenia appear to cope best with a regular routine of meals, sleep, work and recreation. Living with people who are calm, matter-of-fact and warm without being intrusively close seems to be very beneficial. Patients who went to live with families that were more emotionally involved (highly EE - emotionally expressive) showed greater likelihood of relapse, this may include members of the family that were more easily stressed or showed greater hostility.

Some research is being done on the effectiveness of certain therapies such as music-making, art, dancing and writing poetry. It seems that non-rational expression can be helpful to those suffering from schizophrenia, perhaps as a way of emotional output.

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