You wake up angry at someone sleeping next to you who has done nothing. Or at a friend you have not seen in weeks. You know the dream did not happen, but the anger is real and lasts until the afternoon. Psychology has an explanation for that, and it is far more interesting than any dream dictionary.

„Dreams can trigger very strong emotions,” says psychologist Maria de Moya Marin. „Even though we know what happened was not real, the brain experienced those emotions as if they were happening at that moment.” Hence waking up with anger, sadness, fear or even joy. The brain does not keep a record of what was true, but of what it felt.

The brain does not switch off, it sorts

What science knows for certain is not what dreams mean, but what happens while we sleep. „Today we know that while we sleep the brain keeps working. It consolidates memories, regulates emotions and reorganises the day's information,” the psychologist explains. But that does not mean every dream conceals a message. As the specialist herself puts it, „we still cannot claim that every dream hides a specific message or a prediction about the future”.

Some theories hold that dreams have a protective role. „There are theories claiming that dreams prepare us to anticipate threats, which is why we often remember running to get to work, falling off a cliff or losing money,” says de Moya Marin. In other words, the brain does what it does best - it prepares in advance in order to protect us.

Why somebody shows up in your dream

Here psychology is unromantically simple. If you have spent hours talking about someone, thinking about someone or worrying about someone, they will walk into your dream. „That is completely normal,” says the psychologist. „While we sleep, especially in the REM phase, the brain continues processing information, consolidating memories and organising the day's experiences.” So it is not a sign. It is traffic.

But here comes the part most people overlook: the fact that somebody appeared in the dream does not mean the dream is about them. „From a psychological standpoint, this does not necessarily mean the dream has meaning or is sending us a hidden message,” de Moya Marin explains. Often, she says, „the main character in a dream is simply a ‚vehicle‘ the brain uses to process emotions, worries or internal conflicts”.

The real main character, then, is not the person - it is the emotion that person stirs up.

When it is worth stopping

In most cases, the feeling after waking fades as the day goes on. But not always. „If the dream connects with insecurities, previous conflicts or real worries, it can temporarily affect the way we behave towards that person,” the psychologist warns.

And here is the one piece of advice worth remembering from this whole text. „If the same content repeats often and creates significant discomfort, it can be useful to ask ourselves which emotion that dream is trying to express, and whether there is some aspect of our life that needs attention,” says de Moya Marin.

So the question is not „what does it mean to dream your teeth are falling out”. The question is „how did it make me feel” and „is there anything in my life that resembles that emotion”. Years of interpretations about ex-partners, falling into a void and lost teeth have no scientific backing. What does have backing is simpler and more uncomfortable: dreams are not a window into the future, but into how you feel right now.