Diagnosing depression

- [Voiceover] I wanna take a minute to talk about how clinicians diagnose depression or put in different way, I wanna talk about how clinicians can separate depression from normal and appropriate emotional responses. And they do this by using the DSM-5, which is the Diagnostic and Statistic Manual of Mental Disorders, and this manual outlines the criteria that someone has to have in order to be diagnosed with depression. And there are nine different criteria that I wanna focus on in this video. The first criteria is that they must have the depressed mood every day for most of the day. And this has to last over an extended period of time. And whether or not someone actually has a depressed mood is something that can be determined with self-report, but it can also be determined by observations from people around them or by the clinician. With depression, we also expect to see a loss of interest and enjoyment in activities that they once found pleasurable. And this also must be present for most of the day and over an extended period of time. Depression is also associated with a number of cognitive symptoms. And this could include intense feelings of worthlessness and guilt, so feeling like you won't amount to anything or not understanding why anyone would even wanna be friends with you. And of course this can lead them to not going out with their friends and then feelings of guilt for not calling, and so this can kind of become a cycle. People with depression can also have a hard time concentrating. So they might have a hard time focusing on the things that they need to do, things like getting their schoolwork done. These problems with concentration are also associated with an inability to make decisions, and this could be for big life events like choosing a college, but this indecisiveness can also affect small, seemingly insignificant decisions, things like figuring out what to order for dinner at a restaurant. Another cognitive symptom that individuals with depression might have are thoughts about death and dying, and this could include having an actual plan for suicide, but it can also include thinking about death more generally or just not wanting to be around anymore. And this next part might surprise you, but depression also has a number of physical symptoms. It doesn't just impact people on a psychological level, so there could be significant changes in weight, and that could include either weight loss or weight gain. And this can go along with a corresponding increase or decrease in appetite. Individuals with depression might also develop insomnia, so they might have trouble getting to sleep, or they might wake up frequently throughout the night, but it's also possible that they might develop the opposite problem. They might start sleeping too much, enough that it significantly gets in the way of their day-to-day responsibilities. Another physical symptom can be psychomotor agitation or retardation, and let's break this one down a little bit. Psychomotor agitation is an increase in unintentional movements, so this could include things like pacing around a room or wringing your hands or tearing and picking at the skin on your fingernails. Psychomotor retardation is generally the opposite, so this is a slowing down of movements, and I don't mean running in slow motion. It is more like an inability to get out of bed or dress oneself or shower, or maybe a person might feel completely unable to cook for themselves or to return a phone call or an email. And I really wanna be clear that this is not out of laziness. An individual with depression might really feel like these tasks are impossible. And individuals with these symptoms are typically pretty confused about this, and they're really angry about this symptom, and they might feel a lot of guilt about it. The last physical symptom I wanna mention is fatigue or a loss of energy or feeling like they don't have the energy to do the tasks that they like, much less the tasks that they have to do, the tasks that need to get done. So these are the symptoms of depression as listed in the DSM-5, but they have a few caveats. They have a few qualifiers. The first is something that I mentioned earlier, but didn't really wanna repeat with every symptom, and that's that each of these symptoms need to last for most of the day and need to be present nearly every day, generally for at least two weeks. Another thing to note is that someone doesn't need to have all nine of these symptoms in order to be diagnosed with depression. They actually need to have as few as five. But now matter how many symptoms they have and often people do have more than five, they always have to have at least one of these first two, so they either have to have a depressed mood or a loss of interest in pleasurable activities or both. Another criteria is that these symptoms must cause distress, meaning that they must disrupt a person's normal functioning in some way, so maybe they're interfering with someone's work or their grades or their social life. And lastly, these symptoms can't have been brought on by another disorder or as a side effect of medication. One last thing that I wanna bring up is that these criteria have changed over time, so I've gone over a list of symptoms from the DSM-5, which is the most recent version. But prior to the publication of that manual, we had the DSM-4. And while most of the symptoms of depression have stayed the same from the DSM-4 to the DSM-5, I want to mention one big change, and that's the bereavement exclusion. So just like we talked about how you can't meet the criteria for depression if that depression is brought on by a different illness, it used to be that you couldn't immediately meet the criteria for depression if that depression came after a significantly negative life event. So if someone felt depressed after the death of a loved one like a parent or child or spouse, they couldn't immediately meet the criteria for major depressive disorder. Instead, their experience with grief would have to last a lot longer in order to get the diagnosis, and that's something that's been removed from the DSM-5. And of course as our understanding of depression increases, our knowledge about how to diagnose it and how to treat it will also to continue to evolve.