Traumatic incidents may still reoccur in the human brain even after the event has passed, which may result in post traumatic stress disorder (PTSD).
Although it is apparent the hippocampus plays a crucial part in memory formation, the actual physical nature of fear’s long-range storage as a distant memory “has remained elusive.
In a new study on rats, researchers from the University of California, Riverside, in the US have described a few of the key mechanisms whereby distant fear memories are consolidated, and also determined the physical embodiment of distant worries in a visible section of our brains.
We might be able to produce much better solutions for individuals that suffer from flashbacks in case we comprehend how they get lodged in our memories.
Scientists utilized mice engineered with nerve cells that could be identified very easily during fear reactions, in addition to a blend of viruses which cut crucial nerve pathways believed to be associated with mind consolidation, and helped identify crucial connections between neurons.
For the transgenic mice, an electrical shock performed like a memory – fear event. One month later, when the test subjects went back to the shock area, they froze, indicating that distant fear memories were being remembered somewhere in the human brain.
A close examination of different brain samples found a constant strengthening of contacts inside a small set of mind neurons in the prefrontal cortex (PFC), an area accountable for decision making and cognitive behavior.
Additional tests confirmed that when these particular memory neurons have been cut off, the mice had been not able to remember remote fears, while still recalling recent stress. Put simply, PFC – memory – neurons make the actual physical components or engrams for distant fear memories.
The mice were then subjected to the same locations, though this time with no negative stimulus. The scientists discovered this was sufficient to lessen the dread effect and alter the circuitry of these neurons applicable to the traumatizing event.
“It is the prefrontal mind systems which are gradually strengthened following traumatic events, and this strengthening plays a crucial part in how fear memories develop to stabilized types for permanent storage in the cerebral cortex,” Jun-Hyeong Cho, a prominent neuroscientist, said.
“other non-fear remote memories may be kept in the PFC using a similar mechanism,” said he.
In order to better comprehend these systems, there’s far more work being done. They aspire to discover whether selective weakening of PFC memory circuits will stop the recall of remote fear memories, which may inform treatments in individuals.
“The extinction of remote fear memory weakened the prefrontal mind components which were at one time strengthened to keep remote fear memory, “Cho explained.
“other manipulations which obstructed the strengthening of PFC memory circuits likewise prevented the recall of remote fear memory,” it stated.
Approximately six percent of the US population is likely to experience some sort of PTSD in their life, and understanding how these memories get stored and then brought back will be essential in discovering how to deal with people with trauma-based disorders and fear.
The research has been published in Nature Neuroscience.