Pioneering multidisciplinary research in cognitive neuroscience has long been conducted in Turku. In the early 1990s, a cognitive neuroscience research centre was established in Turku, where Antti Revonsuo himself began his career. Revonsuo and his associates also authored Mieli ja aivot: kognitiivisen neurotieteen oppikirja [eng. Mind and Brain: Textbook on Cognitive Neuroscience], the first Finnish textbook on the subject, the first edition of which was published in 1996. Professor Antti Revonsuo is a familiar name to the general public, and he has become known for his pioneering research on dreaming and consciousness.
Antti Revonsuo’s research team is the only one in Finland that studies the biological function and the contents of dreams. Dreaming is the most common altered state of consciousness, and it occurs naturally in all, so this is an important subject of research for the general public.
- Antti says: “In terms of the brain and subjective experience, dreaming is a very similar phenomenon to our waking consciousness, where we find ourselves in the middle of a world of perception. They are practically one and the same phenomenon in terms of experiences and brain activation. The only difference is how that information is streamed into the system. So does it come from inside or does it come online through the senses. The task of the brain is to form a model of the world in which we feel we are inside the model. In that sense, we are always dreaming, but when we are awake, the senses guide the dream so that it is coherent and enables sensible functioning in the physical environment.”
At the source of domestic dream research
Antti’s multidisciplinary approach to phenomena was already visible when he was a student, when he studied biology and philosophy in addition to psychology. He was interested in dreams and consciousness already during his studies, but they were hardly taught at the time because there was very little research in the field, even internationally. Antti’s research career therefore began with a very independent reading of the literature in the field, and with it he gradually developed his own expertise and research direction. Together with his then fellow student, Christina Salmivalli (now a professor of psychology), he set out to collect dream reports and analyse them using the so-called content analysis. Antti recalls the early stages of his research career as follows:
- “When I started doing my dissertation, I thought I would try to do at least some kind of sleep research. I did not have any supervisors for it, so it was all done by me. I thought I would read the literature and see if I could do something with it. If it doesn’t work out, I won’t tell anyone and if it works out, i.e. I can get some publications done, then I can become a legitimate dream researcher. And then it did work out – I managed to publish some articles for my dissertation.”
Threat Simulation Theory of dreaming
Already in the early stages of his career, Antti began to focus especially on the threat contents of dreams. He found that in dreams, negative contents are more common than positive ones, and through his observations he ended up formulating a Threat Simulation Theory, according to which dreams prepare us for various threatening situations. Events are drawn from lived life, but threats in dreams are usually much more threatening than in real life.
- According to Antti: The contents of dreams turn out to be negative more often than would be likely compared to our waking lives. Many old theories see a psychotherapeutic function for dreams, i.e. that dreams help us to deal with difficult emotions. According to the Threat Simulation Theory, threat simulations reactivate the worst fears because they depict events we have to be prepared for.”
Prior to this, the threat content of dreams had never really been looked at, so the theory represented a new, biological perspective on dreaming. At this point, Katja Valli, now an adjunct professor of psychology, came to do a master’s thesis under Antti’s supervision and set out to test the hypotheses of Threat Simulation Theory. The topic later resulted in a dissertation and the supervision relationship turned into a long-term research collaboration. Both have their own strengths: Antti has a strong theoretical background in philosophy and consciousness research and Katja has a lot of practical skills in, for example, sleep laboratory research. They have supervised several dissertations together as a team. Dreams are one phenomenon of consciousness and through the study of dreams they also explore consciousness more broadly.
Social aspect of dreams
The Threat Simulation Theory was especially criticized for the fact that not all dreams are always negative, so Antti and Katja started to develop a new kind of dream theory.
- “I started to work on what could be a similar type of simulation function related to positive dreams that would have been useful in the history of evolution. I ended up presenting a social simulation function. There is also a social life bias in our dreams, which means that we always have a lot of people in our dreams, we really rarely dream of being alone, even though we spend a lot of time alone in waking life. However, few have dreams where they are alone. There are always a lot of people there: family members, fellow students and other important people.” Antti ponders.
The Social Simulation Theory of dreams was formed from this. A very large portion of the brain’s capacity is directed to the processing of social information. Both the Threat Simulation Theory and the Social Simulation Theory complement each other well. Jarno Tuominen, a doctoral candidate, also participated in the formulation of the Social Simulation Theory and testing the hypotheses; Jarno defended his doctoral dissertation on the 4th of March 2022, under the supervision of Katja and Antti.
According to Katja, the simulator of our mind works regardless of the brain’s state of consciousness: asleep or awake.
- Even when we are awake, we do not all the time focus on sensory information in the environment, but the mind wanders for much of the day and a very large part of mindwandering is directed to the future. Our mind is not meant to stay in the moment, it is designed to predict what will happen next based on what you know about the past. Mindwandering is, of course, more voluntary and more controlled than dreaming, but in both the brain simulates possible future events and prepares us to face them.
Defining dreaming as a simulator of the waking perceptual world is currently the definition best accepted among dream researchers.
Epidemiological research of dreams
According to Katja, nearly half of the population occasionally has nightmares and a small but significant proportion, about 3-5%, have nightmares often. The national FINRISKI survey, conducted by the Finnish Institute for Health and Welfare (THL) every five years since 1972, has also included a question about nightmares, which Katja and Antti, together with Nils Sandman, who defended his doctorate dissertation on the subject, have been able to utilise. The group has found that nightmares are associated with symptoms of depression and insomnia. They also found that Second World war veterans and the entire war generation had nightmares more often than those born after the war. In addition, although the number of people who frequently have nightmares has remained relatively similar from year to year, occasional nightmares were reported to be experienced more e.g. after the recession of the 1990s. Thus, major societal events affect nightmares in the Finnish population, possibly reflecting the activation of the threat simulation mechanism when our physical or mental well-being or livelihood is at stake. Previous studies in collaboration with Raija-Leena Punamäki, trauma researcher and Professor of Psychology at the University of Tampere, have also shown that threats reflecting real experiences were common in the dreams of Kurdish and Palestinian children and adolescents who had experienced war or military occupation.
During the COVID-19 pandemic, the team also collected data on changes in dreams and mindwandering as well as well-being during the pandemic in collaboration with Monash University in Australia and the University of Cambridge and Queen Mary University of London in Britain. A similar collection of data related to the war in Ukraine is now taking place in Finland.
Not only do events during wakefulness, but also how our mind works when awake affect how we dream. The same brain connections that have been strengthened during wakefulness are also reflected in the contents of our dreams. Indeed, people who are depressed and anxious have more negative content in their dreams.
- “The way we react to the world while awake is also visible in our world simulation when we sleep”, Katja thinks.
Anxious people are afraid of something that has not yet happened, and depressed people ruminate and repeat the same negative thought patterns in their minds whether they are awake or asleep. This is an important aspect for treatment and therapy, because in the light of this new knowledge, we can no longer consider dreams as psychotherapy, but rather as reflections of what a person is dealing with while awake. Thus, intense negative dreams, such as nightmares, do not help us deal with our concerns, but may be rather detrimental to an individual’s well-being.
Dream research meets anesthesiology – neural correlates of consciousness research project
Since 2006, Antti and Katja have collaborated with the Faculty of Medicine’s Anaesthesia Mechanisms Research Group led by Harry Scheinin in the PET Centre. With the help of anesthesiology, researchers have been able to utilize experimental setups in which consciousness and awareness are in a way turned off and on by anaesthetics. Even during natural sleep, consciousness seems to be on when we have dreams, but on the other hand sometimes off when we are not dreaming. The collaborative group has used EEG and PET imaging to study what happens in the brain when consciousness is connected to the surroundings compared with, when consciousness is disconnected from surrounding stimuli.
They found in their study that, at the level of the brain, sleep during light experimental anaesthesia is quite similar to natural sleep and that dreaming also occurs during anaesthesia. This study is ground-breaking, as it has been possible to study the effects of anaesthesia and various anaesthetic drugs on the content of consciousness in healthy subjects and to compare them directly to natural sleep and dreaming. Previous studies of sleep during anaesthesia have been based mainly on surgical patients with varying anaesthetics and it has been difficult to distinguish whether dream contents were associated with sleep during or after anaesthesia, i.e. whether dreaming occurs during anaesthesia or during recovery from anaesthesia.
Finns teaching in Sweden
In addition to their research work, both Antti and Katja teach consciousness research and neuroscience at the University of Skövde in Sweden. Antti has been involved in founding two bachelor’s programmes in cognitive neuroscience as well as the Mind and Brain master’s programme. The master’s programme is part of the Network of European Neuroscience Schools (NENS). The master’s programme in Human Neuroscience organised by the University of Turku is also part of NENS, which enables wider educational cooperation.
Participate in research
Now you too have the opportunity to participate in this group’s study that aims to understand how the war in Ukraine affects the content of our minds as we sleep or let our minds wander. The survey is conducted online completely anonymously, in Finnish, and individual responses cannot be linked to specific persons.
Here is the link to participating in the War in Ukraine on Our Minds research: