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Introduction to mental disorders

Created by Matthew Barry Jensen.

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Video transcript

- In this video, I want to introduce mental disorders. Mental disorders. And that refers to disorders of the mind. That's what this term mental means. Mental disorders. And people use a number of different terms for the mental disorders. You'll hear people talk about mental illness and psychological or psychiatric disorders. And, for the most part, people mean the same thing when they're using those different terms. The mental disorders are a major public health problem involving mental abnormalities, abnormalities of the mind, that cause distress or disability. And can sometimes even shorten a person's life span from suicide or negative impacts on other medical conditions a person might have. Mental dysfunction affects the higher functions of the nervous system performed by the brain. Functions that can be grouped into categories, such as cognition, emotion, and consciousness. Mental disorders tend to come to the attention of other people by abnormalities of behavior. Or, sometimes, when somebody's describing experiences that they're having that are obviously abnormalities of the mind. There are many ways that people have thought about the causes and the classifications of mental disorders. A big picture distinction that's useful to consider is what has been called the biomedical versus biopsychosocial approaches. Let me write those out. So the first is the biomedical, biomedical. And the second is called biopsychosocial. So, bio, psycho, social. Now the bio part of both of these terms is short for biological. Or, I like to think of, as physical abnormalities. Physical abnormalities. And this can be things like abnormalities in the molecules of the cells of the brain that affect how they function. Or abnormal patterns of connections between the neurons in the brain. The biomedical approach really focuses on these physical abnormalities, these biological abnormalities. And the biopsychosocial approach also considers physical abnormalities that may contribute to the cause or be useful for classifying a mental disorder. But then also tries to include psychological, and the psycho is short for psychological, and social, or cultural factors. The males would be important contributors, either to the cause of the mental disorder, or classifying the mental disorder. Now whatever approach you take to trying to categorize mental disorders can be very difficult. Because for most of them, there are few or no useful tests, such as brain scans or blood tests, and the diagnosis must be made clinically based on symptoms and signs, the time course, risk factors, and epidemiology. As of 2014, when I'm making this video, there are two classification systems that are most commonly used for mental disorders. And that's the ICD-10 and the DSM-5. The ICD-10 is short for the International Classification of Diseases Tenth Revision. And this is a system from the World Health Organization, I'll just write WHO for short, which is headquartered around here in Europe. Although, really, people that work for the World Health Organization work all over the world. And the other system in common use is called the DSM-5, which is short for the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. And this is from a group called the American Psychiatric Association. And I'll just write APA for short. And they're headquartered in the United States, around here. Although they also have people really that work all over the world in mental disorders. And these two categorization systems are similar but they're not exactly the same. For example, the DSM-5 has more top level categories than the ICD-10. So, that the ICD-10, here, has an 11 top level categories. Whereas the DSM-5 has a 20. So, there are some differences in just the way the systems are set up in regards to how many categories there are, where the different disorders get placed into the categorization system. Now before I end this very short introductory video on the mental disorders, I just want to give a couple of numbers to give you a feel for how common these are and how big of a public health problem. According to the National Institutes of Health, which is based in the United States, around here, each year in the United States, just among adults, about 25% will meet criteria for at least one mental disorder. And about 6% of US adults will have a serious mental illness that causes significant distress or disability. And some people may even have more than one mental disorder at a time. So that mental illness is very common problem and a leading cause of disability having a major public health impact.