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Working through the night -

When it comes to forming and consolidating memories, our brains do much of the work while we are asleep.

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Making memories -

Having spent the day gathering experiences, our brains turn these into memories by briefly replaying them as we catch our z’s.

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Area of scientific interest -

For some time now, scientists have been interested in how this process can be manipulated in order to erase negative memories and/or reinforce good ones.

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Exciting development -

According to a study recently published in PNAS, a group of international researchers may have made a breakthrough.

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A word from the researchers -

In their own words, the findings of the study “open broad avenues for seeking to weaken aversive or traumatic memories.”

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The study -

The experiment in the study lasted several days, and involved a group of 37 participants.

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Negative images -

In the first stage of the study, the participants were trained to link negative images with nonsense words made up for the purpose of the study.

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Negative images -

The images that the participants were shown were objectively negative. Examples included injured people and dangerous animals.

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Positive images -

The next day, after the participants had slept, the researchers tried to reassociate half of the words in the participants’ minds with positive images.

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Positive images -

This time, the images that the participants were shown were undeniably positive. They included things like peaceful landscapes and smiling children.

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The test -

During the second night of sleep, recordings of the words were played for the participants to hear and for their subconscious to process.

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The stage of sleep -

The recordings were played while the participants were in the non-rapid eye movement (NREM) stage of sleep, since this stage is known to be important for memory.

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Measuring brain activity -

Brain activity was monitored using electroencephalography, and theta-band activity, which is linked to emotional memory processing, spiked in response to the recordings being played.

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Theta-band responses -

Interestingly, the theta-band responses in the participants brains were significantly higher when the positive cues were used.

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Collecting the data -

Over the next few days, researchers used questionnaires to help understand whether volunteers were more able to recall the positive memories or negative memories, or neither.

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The findings -

In general, they found that the volunteers were less able to recall the negative memories that had subsequently been confused with positive ones.

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Positive memories more likely -

For the words reassociated with something positive, positive memories were more likely to pop into the participants heads.

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More positive emotional response -

Moreover, the words reassociated with something positive were also viewed with a more positive emotional bias.

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Conclusions - These findings led researchers to conclude that this type of non-invasive sleep intervention can in fact help modify adverse memory recollection.

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What it means -

This may have implications for the way in which care providers treat mental health conditions associated with bad memories and traumatic flashbacks.

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Memories and mental health -

Mental health disorders associated with negative memories include depression and post-traumatic stress disorder (PTSD).

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Important caveat -

However, it is important to note that it is still early days for this research, and that these results were produced by a small, tightly-controlled lab experiment.

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High level of accuracy -

On the one hand, this is good, because it means that scientists are more able to trust the accuracy of the results.

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Unrealistic -

On the other hand, this is bad, because the study does not necessarily reflect real-world thinking, or the way memories, both positive and negative, are formed in the real world.

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By their own admission -

Indeed, the researchers admit that seeing a negative image in the context of a lab experiment would not have the same impact as witnessing a traumatic event in real life.

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Real traumatic memories -

Indeed, the negative memory associated with the latter of these two events may be considerably more difficult to overwrite.

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Going forward -

It will therefore take some more time for scientists to truly understand how memory overwriting could happen and how long-lasting the effects could be.

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Important progress -

For now, however, this study appears to be a step in the right direction, and the method used to overwrite memories appears to show some promise.

Sources: (ScienceAlert) (Indy100)

See also: The dark truth behind your childhood memories

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