Categories of mental disorders

- [Voiceover] In this video I want to talk briefly about the different types of mental disorders. There is an enormous number of mental disorders, many of which may have overlapping features. For most categories of mental disorders there is usually a stipulation that the mental abnormalities are not due to the use of medications, substances, or another medical condition, in which case the mental abnormalities are considered to be symptoms of that underlying cause rather than a mental disorder in and of itself. Also, because features of mental disorders often overlap with mental and behavioral aspects of some people considered to be within the bounds of what is normal for a person's culture, another general consideration is that the mental abnormalities cause distress or disability. Distress or disability. Distress or disability. This is a key point because that means that a person that's just unusual or eccentric does not have a mental illness, so that a person that's a little weird is not mentally ill. So to give a very superficial overview of the types of mental disorders I'll go through some of the top level categories, and recall that there are two main systems in use currently to categorize the mental disorders. There is the ICD-10 from the World Health Organiazation, and then there's the DSM-5 from the American Psychiatric Association. I'll go through the categories of the DSM-5 just because I'm a little bit more familiar with that system, but there would be a lot of similarities between the two systems. The DSM-5 has 20 top level categories. I'll start with the neurodevelopmental disorders. These disorders involve distress or disability from an abnormality in development of the nervous system that causes mental dysfunction. Let me just draw a little baby here. Let me just draw this little guy, and we'll put some diapers on him to represent a developing nervous system, and particularly a developing brain. There's all sorts of things that can happen to the brain during its development that can lead to abnormal, mental function. Some of the disorders in this category of neurodevelopmental disorders include intellectual disability which was previously called mental retardation. The autism spectrum disorders are in this category, and attention deficit hyperactivity disorders are in this category. Like all the other categories of mental disorders there is also a group within the neurodevelopmental disorders called "other neurodevelopmental disorders" for any that don't fit all the criteria of one of the specific disorders in this category, but when this category is the best fit for the disorder, so I won't mention that again, but just keep in mind that every one of these big categories has an other category at the end of it. The next big category is called the "neurocognitive disorders" which involve distress or disability from the loss of cognitive and often other functions of the brain after the nervous system has developed. Let me just draw a little old person walking along, walking with a cane, and the distinction here between these neurocognitive disorders, and the neurodevelopmental disorders is that with the neurocognitive disorder the nervous system developed, and then lost functions as opposed to the neurodevelopmental disorders where usually the function was never gained in the first place because the abnormality of the nervous system happens during development. There are a couple of big categories of disorders within the neurocognitive disorders. One is called "delirium," and delirium is the name for a reversible episode of abnormalities of cognitive and other higher brain functions from many potential causes such as certain drugs, abnormalities of certain components of the blood, or certain types of infections. Major neurocognitive disorder which is also called "dementia," and its milder versions usually involve irreversible and often progressive loss of cognitive and other higher brain functions from many potential causes such as Alzheimer's disease, or stroke. The sleep-wake disorders involve distress or disability from abnormalities related to sleep. So let me just draw this person over here who's got their eyes closed and they're very sleepy. We'll just say they are sleeping, so here they're snoring away, and this will represent our sleep-wake disorders. Disorders in this category include insomnia, and breathing related sleep disorders that involve insufficient amounts of uninterrupted sleep, and there are other disorders in this category that cause abnormal sleepiness when awake. Additional disorders in this category involve abnormal behaviors during sleep such as sleep walking. The anxiety disorders involve distress, or disability from abnormal amounts of worry or fear. So for these let me just draw a little kind of worried person over here, just looking very worried about this whole situation. Some of the anxiety disorders are specific to certain stimuli which are known as phobias, like a lot of people have a phobia of spiders or snakes. While other disorders in this category are not specific to certain stimuli including a common one called "generalized anxiety disorder." Panic disorder is in this category which involves panic attacks which are episodes of intense anxiety that may cause people to be afraid to leave their homes. The depressive disorders involve distress, or disability from abnormally negative mood. Let me put a frowny face right here to represent abnormally negative mood. The term "mood" is used in several ways. One way the term mood is used is to refer to a long-term emotional state which may be positive or negative. In this way the word "mood" is related to emotions, but emotions are thought of as usually brief experiences often related to specific stimuli like getting something you want, whereas mood is more persistent, and may or may not be related to specific events in a person's life. The second way the term mood is used is as the subjective experience a person has of their emotions, and another term "affect" is often used to describe how a person's emotional state appears to others, so that mood may refer to what a person is saying they feel like they may say they feel sad, while affect may refer to the person crying. In addition to negative mood the depressive disorders often involve related symptoms such as feelings of hopelessness, or loss of enjoyment in activities. These disorders carry a particularly high risk of suicide which is a major cause of death in people with many types of mental illness. Bipolar and related disorders involve distress or disability from abnormal mood similar to the depressive disorders, but the difference is that these disorders may have periods of abnormally positive mood which are called "mania." So let me draw, in addition to this frowny face here, let me draw a very happy face, and maybe a too happy face, kind of a way too happy face for mania. During periods of mania people will often sleep little, talk fast, and may make bad decisions from impaired judgment about the risks of activities, or their own abilities, and this can lead to all sorts of social or legal problems with this category of disorders. Schizophrenia spectrum, and the other psychotic disorders is the next category which involves distress, or disability from what is called "psychosis." So for that let me draw this person up here, and we'll say "up in their brain "they are hearing voices," which is a common symptom of some psychotic disorders. Psychosis involves certain features such as delusions or hallucinations. Delusions are fixed false beliefs not explainable by a person's cultural background such as having special powers, or the idea that one's thoughts are controlled by somebody else. Hallucinations involve sensory perceptions without real stimuli such as hearing voices that are not there. With psychosis disorganized thinking may occur as well as what are called negative symptoms which may involve decreased emotional expression, motivation, or social behavior. Schizophrenia may have any of these features, and the other disorders in this category usually have some of them. The trauma-and-stressor-related disorders involve distress or disability that may occur after mentally traumatic, or stressful events leading to mood, emotional, behavioral, and other abnormalities. Post-traumatic stress disorder is the prototype disorder in this category which has had many previous names because it has been common after wars throughout history. Let me just draw a soldier here carrying his gun to represent somebody who may have post-traumatic stress disorder. I'll give him a helmet, too, but this can occur after many different types of stressors in addition to war or combat. These disorders are common after all kinds of traumatic experiences such as rape, assault, and natural disasters. Substance-related and addictive disorders involve distress or disability from the abnormal use of substances that affect mental functions. Let me just draw a glass of some kind of alcohol here to represent the different substances that can be related to this category, but there are a lot of substances that can affect mental functions, and cause a substance related disorder. These include alcohol, caffeine, cannabis, hallucinogens, inhalants, opioids, sedatives, hypnotics, anxiolytics, stimulants, and tobacco, amongst others. The mental affects of these substances may cause mental abnormalities similar to the other types of mental disorders including mood abnormalities, anxiety symptoms, or psychosis. Other addictions like gambling are also included in this category because they share many aspects of addiction to substances. The personality disorders involve distress, or disability related to personality. Personality involves long-term mental and behavioral features that are characteristic of a person. There is a huge spectrum of personality types that are generally considered acceptable by a person's culture. Personality disorders involve personality features that are outside generally accepted societal norms, and which cause distress or disability. These have traditionally been grouped into clusters. Cluster A often has odd or eccentric behavior. Cluster B often involves intense emotional, and relationship problems. Let me just draw this very intense person over here to represent somebody in cluster B, and cluster C is often anxious, avoidant or obsessive. Disruptive, impulse-control, and conduct disorders involve distress or disability from behaviors that are unacceptably disruptive or impulsive for a person's culture. Let me just draw this person over here shouting very loudly in an inappropriate setting. Obsessive-compulsive and related disorders involve distress or disability from obsessions or compulsions. Obsessions are thoughts that recur involuntarily, and which are often unwelcome. Compulsions are activities that a person feels they must do and which are often related to an obsession. A common example is someone having an obsession that their hands are dirty, and then a compulsion to wash their hands many more times a day than would be normal. Somatic symptom and related disorders involve distress or disability from symptoms similar to those that may occur with illness unrelated to a mental disorder, but the symptoms are of psychological origin with or without also having symptoms of a general medical condition at the same time. An example of this could be someone that has abdominal pain, so they're saying "ow, my abdomen hurts," but there's actually not anything physically wrong with the abdomen. The tissues of the abdomen are just fine, and it's really caused by psychological factors like stress. Feeding and eating disorders involve distress or disability from mental, or behavioral abnormalities related to food. Disorders in this category include anorexia nervosa, where a person takes in an insufficient amount of food. So we'll say this person is turning down a perfectly nice slice of pizza even though they're actually way below their healthy body weight, and another common disorder in this category is bulimia nervosa which involves binge eating and purging. The elimination disorders involve distress or disability from urination or defecation at inappropriate times or places. I'll just draw this person over here who has had a urinary accident, and they're trying to cover it up. The dissociative disorders involve distress or disability from abnormalities of identity or memory. So let me just draw this person over here asking "who am I?" Some of the people with these disorders seem to have multiple personalities, or may have lost memory for parts of their lives. The sexual dysfunctions involve distress, or disability from abnormalities and/or performance of sexual activity. So I'll just write R-Rated over here. Gender dysphoria involves distress or disability caused by a person identifying themself as a different gender than that identified by society, so as an example let me just draw a person here who society identifies as being male, and I'll just represent that with pants, but they themselves feel that they are female, and I'll just represent that with a skirt. This category requires an important distinction to be made. If people experience distress or disability regarding gender identity the distress and disability constitutes the disorder. A person identifying with another gender without distress or disability does not have a mental disorder. Previously, there was much stigmatization surrounding this issue, and older categorization systems that did consider identification with another gender as a mental disorder in and of itself. The paraphilic disorders involve people that have distress or disability related to having sexual arousal to unusual stimuli, or what would be considered unusual for that person's culture, so I'll also just point this over to the R-Rating over here. So now similarly to gender dysphoria people that have sexual arousal to unusual stimuli do not have a mental disorder unless it causes distress or disability, or for this category activities related to it could cause harm to another, particularly children or other people without sufficient decision-making capacity for proper consent. The last category is just called "other disorders." I'm just going to draw a big question mark here for this one. The entire purpose of this category is for any person that appears to have a mental disorder causing distress or disability, but one that doesn't fit well in any of these other categories of mental disorder. The vast majority of people with a mental disorder will fit in one of these big categories of mental disorders, but very rarely a person just won't fit, but does clearly have a mental disorder, and that's what this other disorders category is for. So that's all I have time for now, and, obviously, there's a lot more information with all the specific disorders that are contained within these top level categories of the DSM-5, but to keep this video to a reasonable length I'm just going to stop right here.