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Delusional disorder

Visit us (http://www.khanacademy.org/science/healthcare-and-medicine) for health and medicine content or (http://www.khanacademy.org/test-prep/mcat) for MCAT related content. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video. Created by Tanner Marshall.

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  • piceratops seed style avatar for user Jarum
    How does someone determine if someone is "functioning socially"?
    (8 votes)
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    • starky tree style avatar for user thecatinthehat1421
      In the DSM-IV-TR has specific axis used for clarifying information about the diagnosis. This includes what other things may be affecting the person. In the DSM-IV-TR the 5th axis is known as the Global Assessment of Fucntioning and assigns you a score from 0-100 depending on how well you are functioning, with 100 being normally and scores around 10 meaning that they cannot be left alone as they present a severe danger to themselves, or others and cannot attend to personal hygene.

      However, under the new DSM-V-TR they basically combined the first three axis (Clinical disorders, Personality Disorders, and Medical causes) and put the fourth and fifth Axis under different categories. Nevertheless, this shows that there are and have been attempts to try and assess functioning onjectively, yet in the end it will almost always be a subjective assessment.
      (1 vote)
  • leaf blue style avatar for user Challenge1student
    How can someone be "functioning normally" when they're having delusions?
    (5 votes)
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    • piceratops seed style avatar for user Jarum
      Great point. I wonder if it's like a Taxi driver thinking she's the Queen of Sheba. She may still be able to drive you to your destination, but she also might request that instead of tipping her, you fan her with palm leaves...
      Functioning at her job, but not so great at the whole inter-personal thing.
      Just my thoughts.
      (9 votes)
  • purple pi purple style avatar for user Residuum
    Are psychotic disorders exclusive to humans, or is there evidence of any of these in other intelligent animals? And if there were, how would you even test for any of it?
    (3 votes)
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    • leaf green style avatar for user Joanne
      You can observe behavior. There are animals that exhibit fearfulness in areas that they have previously had a terrible experience. There are animals that try to catch things that are not present, appearing to snap at flies for example. There are animals that in the boredom of a cage or stall gain repetitive behaviors such as sucking on their own flank or sucking on an object such as the cage door or the stall door for comfort., as well as swaying, circling or walking back and forth. Fly snapping is probably what you are looking for. People think that might be seizures, stomach troubles, cancer etc. Here is one article:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3500118/
      (2 votes)
  • duskpin sapling style avatar for user Dovewing
    What if a person showing all symptoms of delusional disorder actually does one of the non bizarre acts like being guilty of burning a house down or stealing. Then how would we be able to help that person
    (2 votes)
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  • ohnoes default style avatar for user Jazmyne  Deither
    what is flat affect
    (1 vote)
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  • starky sapling style avatar for user elizabeth
    Is genetics part of the cause of delusional disorder?
    (1 vote)
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  • orange juice squid orange style avatar for user Kutili
    What kind of psychotherapy is effective in treating delusional disorders?
    (1 vote)
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    • starky tree style avatar for user thecatinthehat1421
      ^To add to the above information, Humanistic therapy is based on the idea that people are naturally good, and that you are going to help them think out loud so that they can achieve their best self. It generally works best with Depression, but can be helpful in many other disorders.

      The perspective and technique that I could see being most helpful with this kind of disorder is rational-emotive behavior therapy, a kind of cognitive-behavioral therapy. This basically amounts to the therapist playing the "what if" game, where they are reminding the patient that the event (In this case, their delusions) being true is a very remote possibility, but that even if it was true, then it would not be as bad as they think.
      (1 vote)
  • blobby green style avatar for user Lu
    Where is the line between Delusional and Anxiety/Panic disorder with the belief that you're sick in some way? Is it just method of elimination, if the Anxiety symtoms aren't fulfilled it's Delusions, or is there another difference?
    (0 votes)
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Video transcript

- [Voiceover] So people with delusions have these unusual beliefs that are clearly false but they hold firmly to this notion that the belief is actually true. Various mental disorders including schizophrenia and schizoaffective disorder leave all patients with delusions of some kind. Although a lot of times, these patients will present with other symptoms of psychosis like hallucinations. Delusional disorder on the other hand, is characterized by someone having just persistent delusions. Now every delusion someone has can either be considered non-bizarre or bizarre. In non-bizarre, delusions are plausible, meaning that whatever their belief is, is actually possible but it's incorrect. An example of a non-bizarre delusion could be thinking that you're constantly being followed by someone or thinking that you have an infection when you really don't. A bizarre delusion is one that's clearly not possible. A classic example would be thinking that someone has removed all of your internal organs without leaving any sign of it or leaving a scar of some kind and really sticking to this. It's clearly not possible if the organs are missing without leaving some kind of trace of removal, right? So delusional disorder involves a delusion of some kind either bizarre or non-bizarre without any other symptoms of psychosis like hallucinations, disorganized thoughts and behavior, or other mood disorder symptoms like mania or depression. It's only delusions. Now another big difference here between delusional disorder and other psychotic disorders like schizophrenia is that despite these delusions, the person is able to otherwise function pretty normally in many areas of their life, like socially or in relationships, or at work. Now there's this like whole list of sub-types of delusions that are usually associated with either non-bizarre or bizarre delusions though these sub-types aren't always just in one or the other. Now to kinda get started, delusions of control are delusions that somebody's controlling their thoughts or behavior like, for example, thinking that they're being controlled by aliens and these are usually bizarre as being controlled by someone is considered not quite plausible. Nihilistic delusions are these ideas around the non-existence of themselves or of parts of themselves or even the world so they might hold on to the belief that meteorites are going to destroy the Earth and that the world is actually ending. And delusions of thought broadcasting are where the patient thinks that their thoughts are being broadcasted for everyone to listen to. Delusions of thought withdrawal, on the other hand, is thinking that some of your thoughts have been taken out of your mind and that you have no control over this. And these are all really considered bizarre delusions usually but they don't necessarily have to be. In some of the other types of delusions that are considered non-bizarre and could potentially be possible are ones like persecutory delusions which are actually the most common type of delusions and these involve the theme of someone being followed or cheated or conspired against. An example of this could be thinking that the government's following them because the government incorrectly thinks that they're actually a spy. Delusional jealousy or sometimes called delusions of infidelity is this firm belief that your spouse or significant other is having an affair. Delusional guilt or sin is this belief that you're guilty of some crime and you should be punished severely. An example of this could be thinking that they're responsible for some catastrophe like a house fire or something when they clearly weren't. Delusions of reference are thoughts that some sort of remark or event or broadcast is directed at them or has some sort of special significance like thinking that the news anchor on television is actually trying to communicate directly with them. Somatic delusions are delusions that have to do with bodily functions or physical appearance. Usually something to do with their body being diseased or changed in some way. So it could be thinking that your body is infested with parasites. Erotomania is this delusion that another person, usually like a celebrity, is in love with them. Grandiose delusions are those where the person exaggerates themselves and thinks that they have these special talents or abilities. And finally religious delusions are any delusions with a spiritual aspect although it's important to remember that beliefs that are in line with the person's culture aren't considered delusions. And furthermore, any of these delusions that have been mentioned might be mixed with each other as well. Ok, so just like many other types of mental disorders, the cause of developing these delusions is essentially unknown and research has been pretty difficult because many people with delusional disorder don't seek out treatment or diagnosis. And also, because the definition of delusional disorder has evolved over time. Currently, though, from the Diagnostic and Statistical Manual for Mental Disorders, the fifth edition or the DSM-5, the following criteria are given for our delusional disorder: the delusions must have been present for longer than one month, and they aren't accompanied by any other psychotic symptoms like hallucinations, disorganized speech or movements or negative symptoms like flat affect. Also, functioning hasn't been affected except where it relates to the particular delusion like, for example, if you avoided opening your mail because you thought the post office was trying to poison you. Finally, other causes of the delusions have been ruled out like medical conditions or other psychiatric disorders. As to the treatment, this can be challenging. People with delusions often deny any problems or that there is anything wrong with their beliefs. So sometimes anti-psychotic medications might be prescribed to reduce the delusions but also psychotherapy can be a very effective treatment. Finally the prognosis for delusional disorder is usually pretty good considering that most of the delusions don't significantly impair their daily life. Some patients, though, might get more involved with their delusions and could risk further disfunction or risk harming themselves or others.