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Schizophrenia, a brain disorder, stems from a mix of genetics and environmental factors. It's not about multiple personalities. It alters thinking and behavior, often leading to delusions, hallucinations, and social isolation. Diagnosis relies on clinical interviews, not brain scans or neurotransmitter measurements. It's most common in people aged 16-30, affecting males and females equally. Its onset is often preceded by a prodromal period of declining function. Consequences can include suicide, homelessness, and incarceration. Created by Arshya Vahabzadeh.

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  • spunky sam blue style avatar for user Kaylene
    Really enjoyed, but have a question.
    What exactly is the procedure of diagnosing Schizophrenia? Mri's?
    (4 votes)
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    • piceratops tree style avatar for user Yiran Wang
      DSM -5 Schizophrenia Diagnostic Criteria:
      Step 1: Two or more of the following for a 1-month period:
      --- Delusion;
      --- Hallucination;
      --- Disorganized Speech (e.g. clanging, derailment, incoherence);
      --- Grossly disorganized or catatonic behavior;
      --- Negative symptoms (e.g. avolition, alogia, anhedonia);

      Step 2: Disturbance in functioning (e.g. self-care, interpersonal, work);

      Step 3: Continuous signs of disturbance for at least 6 months, with at least one month of active symptoms;

      Step 4: Schizoaffective disorder and Bipolar disorder ruled out.

      Step 5: Rule of substance and medical condition.
      (18 votes)
  • male robot hal style avatar for user Corbin
    At , He says that people with Schizophrenia have a higher chance of going to prison. If the police knew that said person was mentally ill, would they not instead go to a mental hospital?
    (6 votes)
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    • duskpin sapling style avatar for user Kelly
      Unfortunately, in the United States, many states cannot afford appropriate mental health facilities. People with schizophrenia or other mental disorders may not be properly diagnosed, or they may just not have anywhere to go to be treated. These people may break laws due to their mental illness, and they are taken to jail as anyone else would be.
      (10 votes)
  • blobby green style avatar for user John McCarthy
    If brain scans can pick up on elevated levels of dopamine, how come schizophrenia can't be diagnosed via these tests?
    (1 vote)
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    • leaf green style avatar for user Dave Kerling
      I do not believe we can reduce such a complex and ambiguous mental disorder to dopamine concentration. If we were to scan an individual and the test showed decreased levels of dopamine but the same individual expressed neither positive or negative external symptoms, should we diagnose them as schizophrenic? There are also considerable epigenetic considerations that are still not fully understood.
      (9 votes)
  • blobby green style avatar for user alrafae8091
    why is it less severe in developing countries than in developed ones(i googled it and not totally getting it) ?
    (2 votes)
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  • blobby green style avatar for user Ana Laura Estrada
    What are the positive and negative symptoms of schizophrenia?
    (1 vote)
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  • blobby green style avatar for user alikosarian99
    Is there an actual separating line between schizophrenia and the prodrome (clinically, behaviorally)?
    Thank you.
    (1 vote)
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  • leafers ultimate style avatar for user Justin
    One of my professors insists that schizophrenia is NOT a brain disease. It drives me crazy listing to him, in part because he insists that current research has totally debunked the brain disease model and I know that is not true. Part of his augment is that many with Schizophrenia recover fully without medication. Such as in less developed counties, where social support is higher for those with the disease as they believe it is curable. I feel as if that data could simply be inaccurate as the disease could be in remission, was misdiagnosed or that the varied symptomatology of schizophrenia creates the possibility of misdiagnosis (such as the argument in increase in autusim or ADHD rates).
    (1 vote)
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  • blobby green style avatar for user Charles Freewill
    There have been several studies and meta-analyses demonstrating robust clinical improvements of negative symptoms using rTMS, iTBS, and deep TMS. Such neuromodulation techniques show a lot of promise in treating schizophrenia symptoms (positive and negative). In Israel and Europe, deep TMS is officially approved by health authorities as a treatment for negative symptoms of schizophrenia. Please spread the word so that those treatments can go mainstream! I suffer from (unbearable) anhedonia and am looking forward to trying any one of those techniques to find some relief, because no medication works on negative symptoms. (There is a medication called min-101 currently in clinical trials that shows promise for the treatment of negative symptoms but is years away from being available to the public)
    (1 vote)
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Video transcript

- [Instructor] Schizophrenia is a disorder of the brain. What it is absolutely not, it has nothing to do with multiple personalities. When we think about the brain, we think about things that can cause schizophrenia and there are likely to be many different causes, but we know that it's likely to be a combination of genetics and environmental causes that will be at play, and when I say environmental, that may include things like the experience in the womb and also growing up, childhood experiences, so it's really a combination of these two big factors that leads to abnormalities in the brain, and these abnormalities in the brain can actually be picked up by some of the tests that we have today. Some of our brain imaging tests can show some abnormal changes in some individuals with schizophrenia. We know that some of the neurotransmitters, the brain chemicals, are also abnormal in schizophrenia. In particular, there is a neurotransmitter called dopamine that is often thought to be too high or elevated in certain parts of the brain in schizophrenia, and quite a number of the medicines I use to treat schizophrenia, the anti-psychotic medicines, aim to work against dopamine. Unfortunately, brain scans, measuring neurotransmitters, none of these tests ever diagnose schizophrenia. Schizophrenia is actually diagnosed based on a clinical interview, and that means taking a history, hearing from the patient or their family exactly what's been happening over time, and also observing the patient. Well, why would we observe the patient? Because we know that these brain changes may actually cause changes in how a patient behaves. Their behavior may be altered, and we can further break this down into changes in the way they think and changes in the way they act, and we think about ways that people with schizophrenia may think differently. We start to think about having abnormal beliefs, something that we actually call delusions, and they may also happen to see and hear things that aren't there, something that we refer to as hallucinations. Now, people can have delusions and hallucinations in other conditions, but these are some of the symptoms of schizophrenia. Also, the way that they act may be different. They may isolate themselves socially. They may be somewhat disorganized or somewhat confused in their actions, especially to people looking at them from a distance. They may have something that we call a flat affect, and that basically means they lack emotions on their face. This is by no means an exhaustive list, but we can start to see that the way that they think and the way that people with schizophrenia act, there's a lot of changes here that people would start to feel maybe abnormal or different. Now, let's think a little more widely about schizophrenia. How common is this condition? Well, we know that approximately one percent of people have schizophrenia. The exact number is actually a little bit less than that in the US; it's actually 0.7%, and we know that males are typically affected as much as females, and we know that this is a condition that affects people between the age of 16 and 30. Although it can happen in childhood and in older individuals, this is the most common age group, with males being affected at a younger age than females. When we think about schizophrenia, we should also think about the fact that there is something called the prodrome and the prodrome represents a period of time before schizophrenia, the symptoms are fully present, but it's actually a kind of deterioration in a person's behavior and functioning. Things are starting to go downhill and in the prodrome, typically what may happen is that people will start to demonstrate some of the signs of schizophrenia, but what you will notice is their academic or schoolwork may suffer, and I say schoolwork because if you think about between 16 and 30, and if the prodrome precedes that, you're talking about individuals that are often still in the educational system, but if they're working, the work can suffer. Also, their relationships may suffer. They may exhibit some paranoia or suspiciousness towards other people. Some of their thoughts may be that people are working against them, so they may develop some of these delusional ideas and they may start to act differently. The prodrome then often leads to schizophrenia and we know that if somebody has schizophrenia, they are at risk of having lots of different consequences. For example, they're at a higher risk of suicide, a higher risk of being homeless, and a higher risk of being in prison or in jail. So these are some basics to think about when we start to hear the word schizophrenia. Schizophrenia is a brain disorder that's neurodevelopmental, a combination of genetics and environment, and we can notice that there's differences in brain scans and neurotransmitters, but it's really diagnosed on clinical interview and it affects how people think and act. It's preceded by this prodrome period where we notice a decrease in functioning and schizophrenia has a lot of repercussions. It stops people engaging in society, results in higher rates of suicide, homelessness and incarceration.