Distant Memories of Fear Lurk in Your Brain, And We May Have Found Their Hiding Place

Post-traumatic stress disorder can be caused by the reappearance of traumatic events in the brain after the fact.

The physical nature of fear's long-term storage as a'remote memory' has remained elusive.

Some of the key mechanisms through which remote fear memories are consolidated have been outlined by scientists in a new study.

We might be able to improve therapies and treatments for those who suffer from traumatic flashbacks if we understand how they get embedded.

The researchers used mice engineered with nerve cells that could be identified easily during fear responses, along with a mix of Viruses that cut important nervous pathways thought to be involved with memory consolidation.

The mice were scared by an electric shock. The test subjects froze when they came back to the location of the shock a month later.

The prefrontal cortex is an area of the brain that is responsible for decision-making and cognitive behavior.

When these memory neurons were severed, the mice were unable to recall fears, but they were still able to remember trauma. The PFC memory cells form the physical structures for fear memories.

The mice were exposed to the same places, but without the aversive stimulation. The fear response was reduced and the circuitry of the neurons relevant to the traumatic event was changed.

Jun-Hyeong Cho says that the strengthening of the prefrontal memory circuits is a critical part of how fear memories are stable in the cerebral cortex.

The PFC could be used to permanently store other non- fear remote memories.

More work needs to be done to understand these mechanisms. The researchers want to see if a weakness of the PFC memory circuits will affect the recall of remote fear memories.

The extinction of remote fear memory weakened the prefrontal memory circuits that were strengthened to store fear memories.

The PFC memory circuits were blocked from being strengthened.

Around 6 percent of the US population is expected to experience some form ofPTSD in their lives, and knowing how these memories get stored and then brought back is important in figuring out how to treat individuals with fear and trauma-based disorders.

The research has appeared in a journal.