Brain study reveals how long-term memories are erased

March 31, 2016
Credit: Human Brain Project

Vital clues about how the brain erases long term memories have been uncovered by researchers.

The study in rats reveals how can be the result of an active deletion process rather than a failure to remember.

It points towards new ways of tackling loss associated with conditions such as Alzheimer's disease and other types of dementia.

The findings could also help scientists to understand why some unwanted memories are so long-lasting - such as those of people suffering from post-traumatic stress disorders.

Memories are maintained by chemical signalling between that relies on specialised called AMPA receptors. The more AMPA receptors there are on the surface where brain cells connect, the stronger the memory.

The team led by the University of Edinburgh found that the process of actively wiping memories happens when brain cells remove AMPA receptors from the connections between brain cells.

Over time, if the memory is not recalled, the AMPA receptors may fall in number and the memory is gradually erased.

The researchers also showed that actively forgetting information in this way helps the animals to adapt their behaviour according to their surroundings.

Blocking the removal of AMPA receptors with a drug that keeps them at the surface of the cell stopped the natural forgetting of memories, the study found.

Drugs that target AMPA receptor removal are already being investigated as potential therapies to prevent memory loss associated with diseases such as Alzheimer's and dementia.

However, researchers say that active forgetting could be an important facet of learning and memory. Further research is needed to understand what consequences blocking this process could have on the ability to take on new information and retrieve existing memories.

Dr Oliver Hardt, of the Centre for Cognitive and Neural Systems at the University of Edinburgh, said: "Our study looks at the biological processes that happen in the brain when we forget something. The next step is to work out why some memories survive whilst others are erased. If we can understand how these memories are protected, it could one-day lead to new therapies that stop or slow pathological ."

The study is published in The Journal of Neuroscience.

Explore further: Scientists discover neural mechanisms in mouse brains that indicate that we actively forget as we learn

More information: P. V. Migues et al. Blocking Synaptic Removal of GluA2-Containing AMPA Receptors Prevents the Natural Forgetting of Long-Term Memories, Journal of Neuroscience (2016). DOI: 10.1523/JNEUROSCI.3333-15.2016

Related Stories

Scientists view effect of whisker tickling on mouse brains

February 2, 2015

Researchers at The Johns Hopkins University have succeeded in peering into the brains of live mice with such precision that they were able to see how the position of specific proteins changed as memories were forged. The ...

How drugs can help your brain encode memories

January 14, 2016

Medical researchers at the University of Bristol have uncovered a fundamental mechanism that explains the interaction between brain state and the neural triggers responsible for learning. The discoveries, made by researchers ...

Recommended for you

A turbo engine for tracing neurons

April 27, 2017

Putting a turbo engine into an old car gives it an entirely new life—suddenly it can go further, faster. That same idea is now being applied to neuroscience, with a software wrapper that can be used on existing neuron tracing ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.