I’m a sleep psychologist – this is what your dreams and nightmares really mean (and the truth behind THAT vision of your teeth falling out)

Whether they are hauntingly realistic visions of our teeth falling out or our partner cheating with a work colleague they insisted we need not worry about, we all have strange dreams we can’t seem to make sense of.

Well, now a top sleep expert has shared a fascinating insight into why we can have such vivid experiences during our slumber.

Professor Mark Blagrove, director of Swansea University’s Sleep Laboratory, thinks the reason our dreams can be so ‘complex’, littered with ‘characters, emotions and plots’, is because they are designed for us to share with others.

Some psychologists instead believe dreams are just the brain’s way of processing memories, understanding emotions and processing arguments.

Others say there’s absolutely nothing behind our visions, arguing they are merely a meaningless bunch of thoughts. 

‘There are many debates about why we dream,’ Professor Blagrove told the British Psychological Society’s PsychCrunch podcast.

‘But most researchers will accept that dreams are meaningful and do refer to the individual’s waking life, even if it is in a metaphorical way.

‘They are not copying waking life but often providing plots or scenes related to the person’s waking life to an extent.’

Although many dreams have ‘fictional’ scenes, most people can usually relate to the emotions they experience, he explains. But why?

One explanation stems back to an evolutionary theory that there is a virtual reality going on in our minds while we’re tossing and turning in bed, and we are practicing overcoming threats.

Professor Blagrove said: ‘We dream of threats that happen to us.

‘We simulate these threats that happen in our dreams, to simulate the practicing of overcoming these threats.’

Sometimes these threats are not physical but mental ones targeting our self esteem, causing us to process arguments and ways to argue back with people. 

Dreams are also thought to to help consolidate our memories and make them more permanent, Professor Blagrove said. This process might, some believe, trigger such lucid dreams.

‘In sleep we are consolidating our memories and emotional memories and making the memories more permanent and also linking them with previous memories in our long-term memory,’ he said. 

‘One theory says while the brain is doing that, we actually experience the consolidation, and the experience of the consolidation is our dreaming.’

Not all scientists agree with this, though. 

‘There is also the theory many scientists will hold that dreams are epiphenomenal and they are simply occurring,’ Professor Blagrove said.

‘During waking life we have our daydreaming occurring, which has a function because we can monitor our daydreams and build on them and think about them, and the theory just says that processing ability carries over into our sleep. But there is not purpose to it, it has just not been got rid of by evolution.’

Professor Blagrove believes sharing dreams with others is how we reap the benefits of our life-like visions. 

That’s because sharing dreams gives someone insight into the life of the dreamer and helps to build bonds, he said.

‘Maybe the function of dreams doesn’t occur while we are asleep,’ he said. 

‘Instead, what’s happened is dreams have evolved and the contents of dreams has evolved so that when we tell the dreams to other people when we are awake, at that point you disclose yourself to other people.

‘The reason why dreams are so complex and have these characters and emotions and plots and scenes and scenarios is because that complexity is needed in order for the person to express themselves metaphorically to other people.’

He suggests that because the art of story-telling in humans has historically been important, the act of dreaming serves to this purpose.

One experiment led by Professor Blagrove, published in Frontiers in 2019, involved people opening up about their dreams with others. 

Fascinatingly, it showed listening and telling dreams increases empathy. 

But, unsurprisingly, this benefit of dreaming is only possible if you can remember the dream. 

Although all sleep is important, REM sleep in particularly important because it plays a role in dreaming, memory and emotional processing. 

The majority of our dreams take place during this phase (which makes up roughly a quarter of our slumber) and they tend to be more vivid, according to Sleep Foundation.

You are also more likely to remember a dream if you wake up during your REM sleep period. 

If you stay asleep during that cycle, dreams seemingly just ‘disappear’ and have no lasting effect, Professor Blagrove said.

He explains some psychologists believe the dreams before your REM cycle are just in preparation for the final dream of the night. 

‘The other dreams that occur during the night which we may stay asleep during, they are just part of practicing that function and getting ready for the big long dream that occurs at the end of the night,’ Professor Blagrove said.

It’s also common for people to remember nightmares as they wake up during them.  

Describing a nightmare as a ‘distressing dream with negative emotions to it’, Professor Blagrove explains that some experts believe nightmares are the brains way of overcoming fears and threats and are in fact more functional than dreams. 

An example of this is if someone has lived through a traumatic event such as an earthquake they are more likely to have nightmares about it than people who have not experienced one. 

But others say nightmares are the failure of the function of the dream. 

When you have a dream and you are processing memories and emotions and then instead you have a nightmare, that is a ‘failure of that function occurring’, he said.  

‘Trying to process something that is so distressing that you have been woken up by it,’ he added.