So, the next class of disorders that we are going to discuss is the category of anxiety disorders. Now, anxiety is sort of this vague feeling of fear and apprehension and everybody experiences this. Having some anxiety is just part and parcel of living a life. But it could become a problem when it's irrational, when it makes no sense, when it's uncontrollable, and when it's disruptive. The primary thing that categorizes anxiety disorders is distressing, persistent anxiety obviously enough, but also the possibility of maladaptive behaviors that serve to reduce anxiety. So, the anxiety is one problem but to match people act in certain ways to make the anxiety go away, and these ways themselves cause problems. So, one major type of anxiety disorder is called generalized anxiety disorder, worrying about things all the time. About one in every 20 people get this at some point in their lives and the worry interferes or you're functioning, and at least the physical symptoms like headaches, stomach aches, muscle tension, and irritability. Now, we know that just like everything else we've discussed, generalized anxiety disorder has some genetic component. It is related to genetically to major depression that is if you have family members who have major depression, you are more likely to get generalized anxiety disorder. It's sometimes seen also as possibly caused by childhood trauma. So, the logic here, one way to think about it is that something early in life, either genetic predisposition or a trauma, something terrible that happens, makes you super vigilant, you're on the watch for bad things to happen. Then, when some bad thing does happen or just some major event, some big life change, this could trigger full-blown generalized anxiety disorder. This model that we see here is similar to what we see for other types of mental illness which is one starts out with a vulnerability, a vulnerability to schizophrenia, vulnerability to depression, and then some event triggers it and then makes a disorder emerge. Another type of anxiety disorder, our phobias, which are intense irrational fears and they could focus on objects, they could focus on events or situations and they're often social. Social phobias might manifest themselves as sort of a severe form of shyness. They tend to emerge in adolescence during the teenage years and they're more common in women than men. There's sort of a picture to give you a feeling for how common different phobias are so you can see many people are afraid of snakes or being in high places but not many people are afraid of cats, for instance. We've talked about phobias before in the context of behaviorism and learning theories, and there is a classical conditioning model of phobias where you have something which is initially a neutral stimulus like a dog, but then dog bites you and the pain of the bite, that's an unconditioned stimulus, and so you associate the dog with a bite and all of a sudden, you're afraid of dogs. It's not a crazy theory but it has many problems. For one thing, people typically have no memory of a traumatic experience. I'm kind of have a bit of a phobia about mice and rats just between us, but I've never had a bad experience with them. I know people who are terrified of heights but it's not that they ever fell from something. Moreover, there are many cases where you could have a traumatic experience but it doesn't lead to phobia. A dog would bite you, maybe many of you have been bitten by dogs, but you are not afraid of dogs. So, instead, psychologists lean towards what's called a preparedness theory which is that you're psychologically ready for phobias due to evolution, due to certain other factors, you're ready to be phobic, and then certain things might trigger it off. One of the advantage of the preparedness theory is it explains why the things that we're most afraid of are the things that would be dangerous to us in our ancestral environment. So, spiders and snakes are very common phobic objects even though in a modern world, they're pretty harmless. While cars and guns are not typical objects or phobias even though in the modern world, they're quite dangerous. Another anxiety disorder is obsessive compulsive disorder. Obsessions are irrational disturbing thoughts. These give rise to compulsions which are repetitive actions that exists to alleviate the obsessions. So, for instance, some common obsessions would be checking and washing, so you're obsessed with the idea that you forgot to lock your doors or that you've left one of your children behind so you check them and you count them. Everybody does this to some extent or take washing. You could be obsessed with the idea you're filthy and dirty, and so the obsession leads to compulsion of washing. Now, again, obviously, this sort of makes sense in real life. I think my hands are dirty and I want to wash them. But the problem with obsessive compulsive is they're obsessed with it, they can't stop washing their hands even though at some intellectual level, they know they're not dirty. We know that there are some genetic predisposition to OCD and we know that there's a biological basis it involves to some extent in some mysterious way the neurotransmitter serotonin. So, we know that drugs that reduce serotonin may often help treat people with obsessive compulsive disorders.
