Liz: It's passing for normal, because people think you're normal, and you're not. I just know that I don't want people to know or even have a hint of what they can see at the top of my head. It's an absolute ritual.

All of a sudden, I will wave my hands through my hair, until I find a wiry hair or a hair that feels alien to my head. I'll pull it out. And then I'll take it, and I'll look at it. And if it's got a root that's worth eating, I'll take and I'll bite the root. And I only bite the root. And I'll swallow it. Then I discard the hair.

And it's almost like I've injected something into my body, and it just calms and soothes. It's almost like I'm taking a needle and injecting something that just takes it all away. But the thing is it doesn't take it all away, because you're just stressing yourself out more by destroying yourself.

And being a woman and having the main core of your beauty being your hair, I think that in itself is its own distraction. And sometimes I think I'll like a manged animal. And then sometimes I think I'm fine. I know I'm normal as a person. But deep in the back of my mind, looks-wise, I almost feel almost retarded. And I think that comes through the feeling that I've got from other people.

Narrator: Liz has trichotillomania. She can't resist the urge to pull out her hair. Like millions of others with this obsession, she's quite normal in every other way. But she's been pulling her hair since she was 12. And her bald patch causes her acute embarrassment.

Liz: I always normally wear my hair up, and people don't notice. It's amazing how many people don't notice. But obviously, as you get intimate with someone, they do notice. And I haven't go to that stage yet. And I don't know how I'm going to tackle it. And it's going to be very hard.

It also depends on the person, because sometimes someone brings it up. And sometimes you bring it up. But I suppose after a few drinks, you can always let it out. But it is hard, and you never know how people are going to react, and especially when you've just met someone—

Narrator: Liz has no idea why she started to pull out her hair. But research in Salt Lake City may provide a clue. At the University of Utah, they've made a very interesting discovery in mice. This mouse is perfectly normal, apart from one thing.

Doctor: What these mice do is overgroom themselves. And they initially start by just removing all the hair. For example, on this particular mouse, you can see that on the side, its hair's been removed. And what it'll do is continue to remove that hair until all its body hair that he can reach will actually be removed.

Narrator: These mice have been specially created. Scientists altered a single gene in a normal mouse, and this is the result. Having found that a single defective gene can produce this behavior in mice, they're looking to see if the same defective gene occurs in humans.

Doctor: Then, we're struck gold. We can treat the disease with different drugs to see which ones are effective and which are not effective, and then explore it in much greater detail. And then if it has that effect, then one can actually go into the patient population and see whether this would also work in human patients.

Narrator: Understanding how gene defects can lead to obsessive hair pulling would be important and not just for trichotillomaniacs. Because faulty genes may also play a part in other more common obsessive conditions.

Liz, the hair puller is also trying an unusual form of treatment. She's tried numerous treatments for her condition in the past. And she's decided to tackle her problem in a very different way.

Hairdresser: [inaudible], and it's actually growing now. We don't shove it right down, because the glue in this will grab.

Liz: It's got to have something traction.

Hairdresser: Yeah.

Liz: Is it just the outside that you glued?

Hairdresser: Yes. The middle is all free.

Narrator: She's having a hair piece made, which will be glued to the top of her head. She hopes that by wearing it for a few months, she will break the cycle of hair pulling. The color's really good. The glue will loosen up in four to six weeks. You will feel when you need to come back.

Liz: Sophia, thank you so much.

Hairdresser: No problem.

Liz: I feel like I've turned from a frump to a princess.

Hairdresser: Go ahead. There.

Doctor: It seems to have gotten really strong actually since the last time.

Hairdresser: It is. It is very bushy.

Narrator: It's been three months since Liz had her wig fitted. Now she's going to see how her hair has been doing, protected from her pulling fingers.

Liz: [inaudible], tell me what the regrowth is like. Is it quite bushy?

Hairdresser: Oh god, it's excellent. I'm amazed. I'm really amazed.

Narrator: The wig goes back home. She'll wear it for a further six months. But has this actually changed anything?

Hairdresser: Okey doke. Are you ready for the road again?

Liz: I do pull sometimes. But I know it's something that's not going to come overnight. But the pulling that I'm doing now is nothing compared to what I've been doing. And I probably pulled 20 times in the space of four weeks, so there's definitely a vast improvement. And the urge has dissipated completely.