Scientists have discovered the cause of false brain reactions to imaginary danger

Canadian researchers from the Douglas Research Centre at McGill University and the University of Toronto Scarborough have found that the feeling of fear does not enhance the brain's ability to distinguish between safety and danger, but rather blurs the boundaries between them. As reported by ScienceDaily with reference to the results of the work in the journal Nature Neuroscience, this evolutionary survival mechanism may explain the nature of the development of anxiety disorders and post-traumatic stress disorder (PTSD).

During the experiments, scientists combined augmented reality with the visualization of mouse brain activity in real time. The animals were placed in a special arena and virtually moved between a safe and a dangerous environment by changing visual and auditory signals. At this moment, miniature microscopes recorded the reaction of hundreds of neurons in the hippocampus, the area responsible for learning and memory.

Instead of separating neural maps, the researchers recorded an overlap of brain activity patterns: representations of safe and dangerous experiences became less differentiated. According to the study's authors, such an overlap allows the brain to retrieve memories of threats significantly faster and switch to a defensive mode, sacrificing the accuracy of the analysis for the sake of reaction speed based on the principle of over-caution.

Experts believe that the excessive sensitivity of this system leads to panic reactions in people with anxiety and PTSD, when a harmless sound or image mistakenly triggers traumatic memories. Rethinking the mechanism could serve as a basis for creating new therapeutic methods, although scientists still need to conduct additional research to confirm similar processes in the human brain.