A study has shown the emotional reaction that fear provokes in people, be it positive or negative. This is the first time that a research work has identified an electrophysiological marker of fear in the brain , that is, the way in which our brain processes this emotion.
The experiment, carried out by scientists from the Center for Mental Health at the University of Texas in Dallas (USA), involved 26 adults (19 women and 7 men) aged between 19 and 30 years . They were all shown 224 random images, among which were real images (divided into images of danger and pleasant situations) and unreal images without any distinguishable element. Using electroencephalography throughout the experiment , participants were asked to press a button with their right index finger when viewing a real photo and to press another button with their right middle finger when viewing unreal photos.
“We know that groups of neurons fire in and out to create a frequency and pattern that tells other areas of the brain what to do. By identifying these rhythms, we can correlate them with a cognitive unit such as fear, ”says John Hart, Jr., a co-author of the study.
EEG results revealed that threatening images elicited an early increase in theta wave activity in the occipital lobe (the area of the brain where visual information is processed), followed by a subsequent increase in theta activity in the frontal lobe (where theta wave activity is produced higher mental functions such as decision making and planning). In the same way, an increase in beta waves related to motor behavior was also identified.
“We have known for a long time that the brain prioritizes threatening information over other cognitive processes . These results show us how this happens. Theta wave activity starts at the back of the brain, at the emotional control center, in this case fear – the amygdala, – and then interacts with the brain’s memory center – the hippocampus – before traveling to the frontal lobe, where the thought-processing areas are located. At the same time, beta-wave activity indicates that the motor cortex warms up engines in the event that the legs, for example, need to move to avoid the perceived threat ”, summarizes Bambi DeLaRosa, leader of the study published in the journal Brain and Cognition .
Curiosities about fear:
About 4% of the population suffers from arachnophobia, the fear of spiders. And it is that certain fears are universal in all cultures.
Perhaps we imagine that people with anxiety disorders, phobias, or post-traumatic stress disorder (PTSD) have irrationally high fear responses to all scenarios, intimidating or not. But people with these disorders show normal fear responses to fearful situations.
Can we eliminate our fears?
It is estimated that 10-20% of the population is afraid of flying. Extinguishing fear is the process of reducing fear by creating non-fearful memory associations. The alternate set of pleasant memories will be completed by these memories (but will not erase) the originals that caused us fear.
