Researchers at the Center for BrainHealth from Texas University have mapped the neurological activity that occurs in the human brain when a person is fearful. “We are trying to find where thought exists in the mind,” said John Hart, Director at the center. “We know that groups of neurons firing on and off create a frequency and pattern that tell other areas of the brain what to do. By identifying these rhythms, we can correlate them with a cognitive unit such as fear,” he said. This is not the first study by the group on what fear is. They have previously looked at ho the heart is affected during fear, and how fear can travel through DNA from generation to generation.
The team used electroencephalography (EEG) to map the brain activity when participants were exposed to frightening images. Theta and beta brainwave activity was mapped during these sessions.
19 women and 7 men, between the ages of nineteen and thirty were exposed to 224 images randomly. The pictures were either real, or just scrambled garbage. The real pictures were either threatening photos of guns, battle scenes and predatory animals, or pleasant images of food, nature and non-threatening animals.
The participants were wearing EEG caps, and were required to push a button for actual photos, and another button for the scrambled photos. The study recorded that scrambled images required shorter response times. And the response time for threatening and non-threatening were virtually the same. No statistically significant difference was found.
The EEG was seen to peak in theta activity in the occipital lobe when threatening photo were seen. This was then followed by an increase in theta wave activity in the frontal lobe where planning and decision-making is done by the brain. The researchers also saw that the brainwave activity similar to motor behavior was seen steadily in the presence of threatening images.
The study was published in the International Journal of Brain and Cognition.