In this interview, you’ll find out:
Falling off a cliff, running away from someone or something, or suddenly finding yourself in your underwear at school – almost everyone has had nightmares. But where do they come from, and what are they trying to tell us? How can we influence them? A great deal of research is being carried out on this topic. At the SRH University’s ‘Nightmare Symposium 3.0’, a number of current projects were presented. Dr Jonas Mathes answered a few questions for us on this topic.
What fascinates you personally about researching dreams and nightmares – and why is it worthwhile to study this topic scientifically?
Jonas Mathes: What fascinates me about dreams is that they show us just what our brains are capable of. They can create entire worlds we have never seen before, find creative solutions to everyday problems and give us a deeper insight into our inner lives. Dreams are closely linked to our quality of life, as they provide insight into what is currently on our minds. It is also important to learn more about nightmares and to find ways to tackle and cope with them. Under certain circumstances, this can also have a positive effect on how we deal with problems and emotions, and thus on our waking lives.
Understanding nightmares
Why do people have nightmares in the first place? What might be the underlying causes, and what role does stress play?
Jonas Mathes: There are various reasons why the frequency of nightmares increases and the likelihood of experiencing them rises. Generally speaking, some people remember their dreams more often, whilst others never do. People who remember their dreams more often have been shown to be more likely to have nightmares, but that is not the only reason. Stress and anxiety in waking life can play a major role in nightmares. Particularly for more emotional people, everyday pressures can significantly increase the frequency of nightmares.
Another factor can be the experience of trauma, though these post-traumatic dreams differ fundamentally from other, ordinary nightmares in terms of how they are experienced and their intensity. These also occur in children and adolescents, which is why Lisa DeMarni Cromer (PhD, University of Tulsa, USA) specifically addresses this topic in her latest study. Furthermore, taking medication can also have a significant impact on one’s dream life.
What exactly is the difference between a bad dream and a clinically significant nightmare – and at what point should you start to worry or seek help?
Jonas Mathes: It is difficult to define exactly where the line lies between a bad dream and a nightmare. There is still disagreement as to whether waking from the dream is a definitive criterion for classifying it as a nightmare or not. It is also reasonable to assume that there is no fixed boundary, but rather that it is a continuum.
You should seek help if the psychological distress caused by them becomes too great and begins to interfere with your daily life. This should be decided on an individual basis, at your own discretion. One possible treatment method for nightmares is Cognitive Behavioural Therapy for Nightmares (CBT-N). However, as this is not particularly widespread and many therapists lack access to it, Kristi Pruiksma (PhD, DBSM, University of Texas, San Antonio, USA) has set up a website offering seminars on the subject, which (as of September 2026) is even accessible free of charge.
Why do some dreams and nightmares feel so real, and why can we remember some dreams whilst others fade away immediately?
Jonas Mathes: Our brain and our consciousness are not simply ‘switched off’ whilst we sleep – they continue to function in much the same way as they do when we are awake. The biggest difference compared to waking life, however, is that whilst dreaming, the body does not (or only to a lesser extent) perceive what is happening around us at that moment. The brain is still active, however. The experiences and emotions we go through whilst dreaming are therefore not as dissimilar to waking life as one might initially think. Bizarre content occurs relatively rarely, but tends to be remembered more clearly. Generally speaking, we are better able to recall emotional dreams in waking life. However, much remains unknown about dream recall and there is still a great deal of research to be done on the subject.
Effects on our lives
What impact can frequent nightmares have on our daily lives – and what happens to us if we consistently get too little sleep or poor-quality sleep?
Jonas Mathes: Occasional nightmares are nothing to worry about, but if they occur regularly, they can cause significant distress and have a major impact on quality of life. Naturally, this also affects the quality of sleep, as you might, for example, go to bed feeling anxious and fearing that you will have another nightmare. Chronic sleep deprivation can have negative effects on both your physical and mental health: problems concentrating, constant malaise, tiredness and constant irritability. Good sleep is basically the cheapest and most effective medicine there is.
Why is sleep so important for our physical and mental health, and what actually happens in our brains whilst we sleep?
Jonas Mathes: During sleep, the body and mind can recover. In the REM phase, memories are consolidated, and during deep sleep, the body regenerates. That is why getting enough sleep is essential for our long-term health.
State of research
What does research into dreams and nightmares actually involve – and which questions remain unexplored?
Jonas Mathes: Dreams and nightmares cannot be measured directly, as we cannot look inside anyone’s mind whilst they are dreaming – we have to rely on reports of dream memories. This can be done through questionnaires, written dream accounts or dream diaries.
A great deal therefore remains unexplored, as empirical dream research has only existed for a few decades. Whilst we know that dream content stems from memories and emotions from waking life, no one yet knows exactly according to which criteria and in what proportions these elements ultimately come together.
