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Schizophrenia symptoms

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Video transcript

- [Voiceover] Schizophrenia is essentially this disorder that's present all the time, or sometimes we say that it's chronic, and it's characterized by someone not being able to tell what's real and what's not real. And it affects about 1% of the general US population, or about three million Americans, with an onset typically happening around the late teens to early 20s. And this is onset is usually brought on by some sort of stressful life event, like starting a new job or going off to college. But about 15 to 20% of cases account for either late onset, which is above 40 years old, or very late onset, above 60 years old. Clinically though, schizophrenia's actually a syndrome, meaning that people can have different types of symptoms. So even like different types of hallucinations, or delusions, but they're all associated with schizophrenia. So when we talk about symptoms of schizophrenia, we can separate them into positive and negative symptoms. And when we say positive and negative though, we don't mean like these positive symptoms are good symptoms, and negative are bad, we mean that these positive symptoms are usually like exaggerations of normal processes that we typically wouldn't see in a quote, unquote, healthy person. So you can sort of think of it like you're adding to, and exaggerating normal behaviors to where they become abnormal. Negative behaviors, on the other hand, are called negative because there's this, like, absence, or reduction in normal processes and behaviors. It's like you're subtracting from normal processes to where they become abnormal. Okay, so positive symptoms, which are also symptoms of psychosis, are things like delusions, which are these false beliefs that someone feels very strongly about, and they won't change their mind even though there's strong evidence against it. For example, a delusion of control where they think some outside force, or person, or thing, is controlling their actions, or maybe like a delusion of reference, where they think that someone is trying to speak directly to them through a television news program, or something similar. And another positive symptom is hallucinations, which are any kind of sensation, usually hearing, or seeing something, that appears very real, but in fact, isn't real. So maybe like hearing voices, or commands, that aren't actually there. And finally there's disorganization, which is either in your behavior, which someone can directly see by the way you act, or thinking, which can be observed through your speech. And this could be like having trouble staying on topic, or having trouble answering the actual question that was asked. So those were all positive symptoms, right? Where normal behaviors and processes are, like, added to, and exaggerated. But negative symptoms, where there's this, like, reduction, or subtraction in normal processes can be split into primary and secondary negative symptoms. And primary negative symptoms are the core features of schizophrenia, and the first major one is apathy. And this is where the patient lacks interest, or enthusiasm, or care towards something or someone else. For example, not caring whether you pass this huge exam at school shows apathy toward that class, and this is negative because they have less interest or care than what would be considered normal. Another major symptom is flat affect, and this is where a patient doesn't have an emotional response, like anger, or sadness, to situations that would normally cause strong emotions. For example, if someone is fired unexpectedly from their job usually you'd expect them to be pretty angry, right? But maybe someone with schizophrenia's reaction would be completely unchanged, or essentially flat. And some other symptoms are lack of energy, and anhedonia, which is an inability to experience pleasure from activities that you used to enjoy. So like for example, if you used to really enjoy going on roller coasters, and you'd have a really awesome time doing this, but now maybe you're unable to experience the same feeling of awesomeness as you did before. So those were primary negative symptoms. Secondary negative symptoms are any symptoms that result from other manifestations of schizophrenia. So maybe something like social isolation, or staying inside because you're paranoid that someone is watching you. This is negative because your actions are reduced compared to a quote, unquote, healthy individual, and secondary because it's caused by paranoid delusions. All of the symptoms listed though are mental symptoms, but there can be physical manifestations too, which is something called catatonia. This is characterized by changes in muscle tone and muscle activity, and this can happen though with a lot of different disorders, psychiatric or not, including schizophrenia, and it may be caused by medications, but other times it could be caused by something unknown. And one type of this is catatonic stupor, which is a decreased reaction to stimuli, like not talking, or being motionless, or just staring off into the distance. And another type is excited catatonia, where you have excessive motor activity and movements, but these movements don't serve any real purpose. It's just like this general state of restlessness.