Fear in dreams can be useful. (Image: Sergey Nivens/ istock)
Thank God it is only a dream! Those who experience fearful situations while sleeping are often happy when their consciousness returns to reality. Bad dreams do have something good about them: they help us cope with negative emotions in everyday life, as researchers report. According to this, fear-inducing situations in dreams function as training for similar experiences in the waking state. Prepared in this way, we can obviously control our feelings of fear better and face threats and danger more prudently.
When we sleep, we plunge into a strange world. In this dreamland, we can experience the most bizarre things, but we can also go through astonishingly realistic situations. Often, these experiences have already faded by the time we wake up and soon escape our memory. But sometimes they keep us busy for days. Researchers have always been fascinated by this phenomenon: how dreams come about? And what biological function do they fulfill? One theory is that dreams help us cope with waking life. According to this, we process problems from everyday life and deal with our emotions in the process.
Fear during sleep
Virginie Sterpenich from the University of Geneva and her colleagues have devoted themselves to the function of a particularly strong emotion: fear. You wanted to know: What happens when we experience anxiety in dreams, and how does it affect how we deal with that emotion while awake? To find out, the scientists looked into the brains of 18 subjects using electroencephalography (EEG) while they were sleeping. In the process, they repeatedly woke up the subjects and asked them about their dream experience. In combination with the measured brain activity, the participants’ responses provided clues as to which areas of the thought organ are active during bad dreams. "We identified two brain regions that play a role in fear experienced in dreams: the insula and the cingulate cortex," Sterpenich’s colleague Lampros Perogamvros reports.
What’s exciting is that both areas of the brain are also activated in real-life anxiety situations. Neurons in the insula, for example, are responsible for evaluating emotions and fire automatically as soon as someone feels anxious. The cingulate cortex, in turn, prepares us to respond adequately in such situations. It helps control how we behave in the face of danger and threat. "For the first time, we show that similar regions are activated when experiencing fear during sleep and when awake," says Perogamvros. But what is the connection between the fear in these two worlds, which are so different after all??
Training for the waking state
In search of an answer, the researchers conducted a second experiment in which 89 subjects were asked to keep a dream diary for one week. Every morning, immediately after waking up, the participants noted down whether they could remember a nighttime dream and, if so, what emotions had characterized it. At the end of the test week, the scientists then examined the subjects using functional magnetic resonance imaging (fMRI). In doing so, they showed them both neutral and fear-inducing images – for example, of a robbery. The striking result: those who had experienced fear more frequently and for longer periods in their dreams reacted significantly less strongly to these negative images.
"Both the insula and cingulate cortex, as well as the amygdala, were less active in this case," Sterpenich reports. In addition, it was shown that at the same time the middle prefrontal cortex was more activated – this brain region can inhibit the amygdala in fearful situations, ensuring that we are not paralyzed or overwhelmed by this feeling. According to the researchers, this points to the fact that there is a strong link between fear in dreams and fear in reality. In a way, the emotion experienced during sleep serves as practice – it helps us to react better in fearful situations when awake. "Dreams could be a training for future reactions and prepare us to face real dangers and threats," Perogamvros states.
How do nightmares work?
This finding may lead to new approaches for the treatment of anxiety disorders, as the scientists explain. But the healing power of fearful dreams may also have a limit – when they are severe nightmares. "We believe: if a certain threshold of anxiety is exceeded in the dream, it loses its function as an emotional regulator," says Perogamvros. Whether this is true, the researchers want to investigate in future studies in more detail. They are also interested in the function of positive feelings in dreams: how do they affect our behavior in waking life?? There is still a lot to find out about the influence of our dreams.
Source: Virginie Sterpenich (University of Geneva, Switzerland) et al., Human Brain Mapping, doi: 10.1002/hbm.24843