Sleep talking: Why do we do it?

Almost all of us have at some point been told that we were talking in our sleep the night before. There's that niggling worry that we've blabbed some deep subconscious desire of which we are normally unaware. Graihagh Jackson - professed sleep talker and walker - wanted to understand why we sleep talk and whether there is any hidden truth behind the babble. She spoke to Karen Slavick-Lennard whose husband Adam went through a phase of prolific sleep-talking and Dr Ian Smith, director of the Sleep Clinic at Papworth Hospital to find out more about the condition...

Karen - It sort of started slowly. It went like a bell curve. The more amused I was, the more often he did it. We did get to a point at the pinnacle of his career where Adam was saying many times a night, nearly every night.

Graihagh - I asked Karen to pick out some of her favourites, but she said there were just too many to choose from. Instead, we opted to pick one recording from each category of which there seem to be three. There's the horrendous insults, most of which I couldn't possibly play on the air, but there is this one about vegetarians.

Adam - You know, the world would be a much better place when we get to eat vegetarians. You'll get your five a day with one of those.

Graihagh - Incidentally, Adam has nothing against vegetarians when conscious. The next topic falls into the bracket of how amazing he really is.

Adam - Here's my CV. Why don't you just file it under awesome!

Graihagh - And then there's the absurdly random.

Adam - Jelly fish are attacking! Everybody grab your ice cream guns!

Graihagh - They're just classic. I feel like they're things that you can't even write. They're so random.

Karen - And the thing is that, awake Adam could never come up with these things. People often ask why I think he came and then why he went. I can only ever theorise about that but what I think is that at this time in our lives, we were under extraordinary stresses. We were having visa problems. Adam was having trouble finding an appropriate job and I couldn't work because I was a visitor in the UK. We were in a very painful and difficult battle for visitation with his kids in court. We were in and out of court. So, we were under extraordinary stress and that's when Adam started talking in his sleep. What I think is that sleep-talking man just became this really healthy way for Adam to turn through all of this anxiety and sort of spit it out in a funny healthy way and in a way that was really well-received. I found every single thing he said totally delightful. I never once minded being woken up. I never got enough of sleep-talking man and I miss him terribly. I really do miss him.

Graihagh - Where could sleep-talking man have gone and why did he come and go in the first place? These are questions I put to Dr Ian Smith, director of the Sleep Clinic at Papworth Hospital in Cambridgeshire. But first, why do we sleep talk?

Ian - So, we don't know why people sleep talk. It seems to be an inherited condition. It's very closely linked with sleep walking and these conditions usually only happen in a particular phase of sleep which is very deep sleep.

Graihagh - So, I'm a sleep talker and a sleep walker, but I don't sleep walk and talk every night. Is there a certain trigger that might be happening during the day that triggers me some nights but not others?

Ian - Well, different people have different triggers. Most people are more likely to have one of these episodes if they're stressed. For other people, it will be a noise then they'll start doing their automatic behaviour, the talking or the walking. For other people, it's more likely if they are sleep deprived. So, if they're very sleepy then it's more likely to happen.

Graihagh - Is it something you might take someone into a lab for, for sleep talking and walking if it really was that disruptive in their night cycle, but also I guess for their partner perhaps?

Ian - So yes, we see quite a lot of people in the sleep laboratory because sometimes they are associated with quite violent behaviour where people are acting as if they're defending themselves but they are striking their partner or kicking out. And sometimes it's not absolutely clear that it is straightforward sleep walking or talking. There are other things that happen in sleep. People can have epileptic phenomena. So, it's important to differentiate them and make sure that we're identifying the people with simple sleep walking and talking where we can reassure them. The other conditions, we may need to investigate them further and consider medication.

Graihagh - Investigating patients further involves a night at the sleep lab. Ian gave me a tour.

Ian - There are six rooms and we try and make it a  halfway house between a hospital environment and a home environment.

Graihagh - It does actually look pretty comfortable. It's bigger than a single bed. It's much bigger than my bed at home. Much more comfortable and you've even got a TV and sink, and a little sofa as well.

Ian - Yeah and the patients will come in in the evening and we wire them up, and if you see at the end of the bed there, the complex electronics are then attached. We record brain activity from electrodes on the scalp and eye movements with electrodes on the eyes because one of the things we're trying to work out is when they're dreaming, we would need to record rapid eye movements. We do that by recording from the muscles around the eyes. We measure breathing because one of the things that sets off lots of behaviours at night is interruptive breathing. We record muscle activity to see when they're moving. The whole thing in the corner, that red light is because there are cameras and infrared cameras. So, they switch off the light and they think they're in darkness, but actually, we can still see what's going on.

Graihagh - Given that there's a camera, does that mean you sit up and watch them all night?

Ian - No. So, in some sleep laboratories, they do that. We keep people under surveillance in case they need any assistance in the night, but usually, all of the information is downloaded and scored the next day. We usually have the answer by lunch time.

Graihagh - That quick?

Ian - Yes. It's all processed the next day. So the patients don't have to make more than one trip.

Graihagh - In terms of treatments then, is it more a case of changing your lifestyle rather than medication or is that often a combination of both until they're better?

Ian - So, we would always with any sleep condition, we would start, first of all, with trying to get people to have the best sleep pattern. So, we would always start with those basics. And only if they're unsuccessful, then we would escalate to think about medication.