Gareth Fletcher regularly had sleep paralysis when he was a teenager. Although it has virtually stopped, he still experiences it very occasionally.

"I first experienced sleep paralysis when I was 16. I remember it vividly. I went to bed one night as usual, but at some point I woke up and was unable to move a muscle. I was conscious and aware that I was in my bed, but my entire body was paralysed.

"It may have only lasted a matter of seconds, but the experience was terrifying. There was a ringing noise in my ears that seemed to get louder, and no matter how hard I struggled, I couldn't move. I had a feeling of immense panic, and an urgent need to move my arms and legs.

"Then suddenly I could move again. While this was a great relief, I was still scared as I had no idea what had just happened.

"The same thing happened again a few nights later, and then it began to happen regularly. It would sometimes happen a couple of times in the same night.

"I became nervous about going to sleep - worried that every time I went to bed I’d wake up and be unable to move. Even though the paralysis was only temporary, it was very frightening.

"I would often wake up suddenly after having a vivid dream. Sometimes this was an unpleasant dream, which made the experience even scarier.

"I didn’t tell anybody about it at first. This was partly because I began to doubt that it was really happening. I thought perhaps I was dreaming it, and although it seemed very real at the time, perhaps it was just a nightmare in which I couldn’t move.

"Also, it happened as I was falling asleep early in the night. By the time I'd woken up in the morning, it didn't seem to matter so much and I tried to forget it had happened.

"Then one day at school, I overheard a friend talking about a documentary he'd seen about this very phenomenon. It was the first time I'd heard the term 'sleep paralysis', and it perfectly described what happened to me, although my friend mentioned that the people on TV had also felt a presence in the room and a pressure on their chest when they woke up, which I hadn't had.

"Knowing that it had a name was a relief. I told my parents about it, and my dad said it happened to him once when he was younger. My mum has since said it once happened to her too.

"My mum then told our GP, who said it was nothing to worry about and that little was really known about it. The GP did say she thought it may be linked to stress.

"The sleep paralysis kept happening, but I no longer felt so panicked by it. It was still very unpleasant and I had a desperate need to move every time I woke up, but I just told myself that it was nothing sinister and I’d be able to move in a few seconds.

"And then it stopped happening, almost overnight, when I went to university. It's odd, but it only seemed to happen when I was in my bed at home. After I left, it virtually disappeared.

"It does happen now, but only very rarely. It can still be frightening, mainly because of the disorientation you feel when you suddenly wake up and can't move. But knowing what's happening and that it's nothing to worry about makes it bearable, and I'm usually able to relax and get back to sleep quickly."