Are some people more prone to fear memories than others?

A recent research study conducted by scientists at Linköping University, Sweden has discovered new information on mechanisms behind the development of strong fear memories and anxiety-related disorders.

Published in the scientific journal Molecular Psychiatry, the study was conducted on rats. Normally, fear is a protective emotion that is supposed to aid in escaping life-threatening situations.

However, in some anxiety-related disorders like post-traumatic stress disorder, the fear reactions can exceed normal expression and continue to exist even when they are not needed.

As a result, the body can remain in a flight or fight mode, leading to disability for people who are affected.

Researchers believe that some people are more prone to pathological fears than others because different people can process fearful memories in different ways.

Some areas in the brain are dedicated to the processing of fear. The amygdala works together with the prefrontal cortex. Both are crucial when it comes to the regulation of emotion, fear being one of them.

The network of nerve cells that connects the two parts are altered in those with PTSD and other anxiety disorders, noted the lead author of the study, Estelle Barbier, who is an assistant professor at the Center for Social and Affective Neuroscience (CSAN), and the Department of Biomedical and Clinical Sciences (BKV) at Linköping University.

Experts have now studied these molecular mechanisms in depth and investigated a protein called PRDM2 which is an epigenetic enzyme. This protein disallows many genes to express themselves.

Low levels of the protein can lead to exaggerated stress responses. PRDM2 is found in fewer amounts in those addicted to alcohol.

Barbier said that they identified a mechanism where increased activity in the network can increase "learned fear reactions".

“We show that down-regulation of PRDM2 increases" the development of fear-related long-term memories, she explained.

Authors said that anxiety patients needed treatments that could either weaken or erase fear memories.

“The biological mechanism that we have identified involves down-regulation of PRDM2, and we currently do not have any way of increasing it."

While there is no way to increase PRDM2 right now, researchers have revealed the explanation behind some people having "greater vulnerability to developing anxiety disorders".