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Researchers have discovered that the brain can remember 'neutral' or boring events more easily when they are tied to an emotion

From what we eat to what we see, we constantly take in details about our environment.

And while there is no need to remember many of them, our brain has the remarkable ability to store information that seems inconsequential at the time in case it becomes useful later on.

Given new and relevant information, human beings have the capacity to strengthen weak memories using emotions - and researchers have said this points to the adaptive nature of human memory.

Psychologists at New York University have been trying to gain an understanding about how the brain stores memories for 'emotionally neutral events' that gain significance through subsequent experience.

'How does the brain store all of this information? And how does emotion strengthen mundane memories?' post-doctoral fellows Joseph Dunsmoor and Vishnu Murty wrote on The Conversation. 

This study largely focused on how our brains remember emotionally arousing stimuli, such as evocative imagery or traumatic events .

In particular, the study has looked into how the September 11 terrorist attacks in the the US affect memory retention.

The researchers said we take for granted that we remember highly emotional events better than we remember neutral events, like a lunch date.

Emotion increases our ability to remember by affecting activity in brain regions involved in emotional processing - particularly the amygdala and striatum - and also the regions involved in encoding new experiences, like the hippocampus.

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Emotion also increases the strength of our memory over time - a process called consolidation.

Strong emotion can strengthen memory for positive events, such as a surprise birthday party thrown by close friends, and for negative events, such as making an embarrassing faux pas at the office holiday party.

Researchers said we take for granted that we remember highly emotional events, like 9/11, better than we remember neutral events, like a lunch date. This is because emotion affects activity in certain brain regions. A view over the Hudson River towards the September 11th memorial lights is shown

While many details are not intrinsically emotionally arousing, they can gain emotional significance through our experiences.

For example, the memory of a surprise birthday party includes details like what people were wearing and who was there.

On the face of it, these details are not emotionally significant but we remember them because of the context in which they were experienced.

Dr Dunsmoor and Dr Murty's research has shown that people have better memory for boring information when it's presented in an emotional context, regardless of if it is rewarding or negative.

'In some of our earlier studies, we found that people selectively remember neutral pictures if the pictures had been associated with an electrical shock the previous day, even when the volunteers were unaware that we would later test their memory, they wrote.

'We have also shown that people remember neutral pictures if they are warned that if they forget them, they will receive a shock the next day.

'Likewise, being rewarded with money for remembering certain pictures the next day can boost memory for those pictures as well.'

These experiments focus on emotional factors at the time the original memory is created and the findings show how seemingly trivial information associated with a meaningful event can be selectively preserved in memory.

Emotion also increases the strength of our memory over time - a process called consolidation. Strong emotion can strengthen memory for positive events, such as a surprise birthday party (stock image), and for negative events, such as making an embarrassing faux pas at an office party

Emotion affects activity in brain regions involved in emotional processing - such as the amygdala (pictured) and regions involved in encoding new experiences, like the hippocampus (also marked)

But what happens when the emotional event happens after the original memories were formed?

'In a recent study, we found that an emotional experience can enhance memory for neutral information encountered previously,' the researchers continued.

Volunteers viewed a series of trivial pictures from two categories, either animals or tools.

After a delay, volunteers were presented with a new set of animal and tool pictures – only this time, when the volunteer saw the pictures they received an electrical shock to the wrist.

'We already knew that memory would be strengthened for the pictures paired with the electrical shock.

But here we found that if we paired shocks with pictures of animals, memory was strengthened for pictures of animals volunteers saw before any shocks were delivered.

'If we shocked volunteers when they where shown pictures of tools, memory for the earlier pictures of tools was strengthened.'

The negative experience selectively increased memory for related information that was completely trivial when it was originally experienced.

We use our memory not only to remember the past, but to guide our decisions in the future.

Emotion helps us remember relevant information to determine our choices, but without the ability to strengthen seemingly trivial past experiences with new important information, we might end up missing out on future rewards or repeating the same mistakes.

Memory Techniques: Remembering names and faces (related)