Are your dreams normal? Scientist reveals the most bizarre phenomena she's encountered - including sexsomnia, sleep paralysis, and false awakenings

All human beings sleep - but it's not always simply a case of nodding off, having a dream and then waking up. From sleep paralysis, false awakenings and lucid dreams, one sleep expert has helped patients overcome and control many of them. Sleep paralysis is when you cannot move or speak as you are waking up, often combined with distressing hallucinations of a terrifying figure holding you down SLEEP PARALYSIS Perhaps the most famous – and terrifying – of sleep phenomena is sleep paralysis, which affects just 7.6 per cent of people. A typical night's sleep goes back and forth between the stages The most bizarre dream phenomena Sleep paralysis: When you cannot move or speak as you are waking up Hypnagogic visions: H allucinations during the transition from wakefulness and sleep Hypnopompic visions: Illusions when we have opened our eyes but are still to properly wake up Lucid dreams: T he experience of knowing that we are dreaming Parasomnias: Physical displays our body performs while brain is asleep False awakenings: T hinking you've woken up in a dream Shared or 'twin' dreaming: When two people share similar or even identical dreams in the same night Aside from great emotional stress, the body can then enter 'a state of physiological fear', according to Anderson. In Christopher Nolan's classic action film Inception, characters consciously navigate through impossible dream worlds Lucid dreams let more have more enjoyable 'trips' or psychedelic adventures when they go to sleep What are nightmares?