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Current time:0:00Total duration:6:22

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.