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Depression and bipolar disorder

Bipolar disorder, previously called manic depressive disorder, involves extreme emotional highs and lows. It includes periods of depression and mania, an overexcited, unrealistically optimistic state. Mania can lead to poor decision-making and risky behavior. Bipolar one disorder involves full mania, while bipolar two involves hypo mania, a milder form. Created by Brooke Miller.

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Video transcript

- [Instructor] One disorder that is very related to depression is bipolar disorder. And this disorder used to be referred to as manic depressive disorder. But this term, bipolar disorder, it describes a condition where an individual swings from extreme emotional highs to extreme emotional lows. And people generally have ups and down in their life, and that is totally normal. But this is something that's different. The individual will have periods of depression with all of the symptoms that we would see with major depressive disorder. But in addition to this, they will also have periods of mania, an over excited unrealistically optimistic state. People experiencing mania have a ton of energy. They are euphoric and optimistic, and they have very high self esteem. And maybe you're thinking to yourself, that really doesn't sound that bad. Sounds like it would be a good time, and I could probably get a lot of work done. And for mild forms of mania which are sometimes referred to as hypo mania, this can be true. They do have a lot of energy and they don't really need to sleep a lot so they get a lot done. And they also feel good so they might also deny that anything is wrong. But if the manic stage continues, if it becomes full blown mania, then all of this is taken to the extreme. And they begin to make poor decisions without any regard for the consequences. They might max out their credit cards while shopping. Or they could end up in financial distress or lose their life savings, because they impulsively backed an unrealistic business venture. They also might engage in reckless behavior. Things like driving too fast or engaging in risky sexual behavior. And while they might have initially benefited from the creative out-of-the-box thinking that can come on with the onset of mania, these thoughts can soon transform into delusions of grandeur and completely unrealistic ideas. So if depression feels like everything is going in slow motion, mania would be everything going in fast forward. They don't sleep. Their heart races. They have racing thoughts. And after all of this, they crash, because mania is often followed by intense depressive episodes. But as we implied before, not all hypo manic episodes develop into full mania. And when they do, we refer to it as bipolar one disorder. And when they don't, when they cycle through hypo mania without going into a full manic state, we refer to this as bipolar two disorder. The way I like to think about these two disorders, and how they relate to major depressive disorders is using a graph. And let's say that this line here represents the normal mood of a completely average person. So here we have positive moods, and down here we have negative moods. And let's say that average Joe is basically a happy guy. He usually has a good mood, and he also has the normal ups and downs that happen in life. Maybe he gets a job and then loses that job, and maybe he meets someone he loves. But through everything that occurs, he basically has normal cycling around this average line. Individuals with depression might also cycle normally for a bit, but sometimes their moods can plunge down to incredibly negative moods. Well below what we would expect to see. And then we have bipolar disorder, and let's look at bipolar disorder one first. And I'll use this pink color for it. And these individuals might also start off cycling normally, but sometimes they will also show periods of mania as well as periods of depression. Bipolar two disorder has a somewhat similar trajectory. These individuals can also cycle normally, but then they have periods of depression and periods of hypo mania. And so this part up here represents hypo mania. And you can see that it's higher than the normal positive moods that average Joe has. But it's also lower than what we would see with bipolar one. And obviously this chart is not up to scale. There is no line here indicating exactly how positive someone's mood is or how negative it is. But if you're trying to picture how these disorders relate to each other, this graph is a pretty good way to do it.