Neuroscience: Forgetting is a form of LEARNING that helps us access more important information

Instead of our memories decaying with time, forgetting is actually an active form of learning that helps our brain to access more important information.

This is the conclusion of experts from Trinity College Dublin and the University of Toronto, who said that ‘lost’ memories are not really gone, just made inaccessible.

Memories, they explained, are stored permanently in sets of neurons, with our brains deciding which ones we keep access to and which irrelevant ones are locked away.

These choices, they said, are based on environmental feedback, theoretically allowing us flexibility in the face of change and better decision-making as a result.

If correct, the findings could lead to new ways to understand and treat memory loss associated with disease — such as is seen, for example, in patients with Alzheimer’s.

The study was undertaken by neuroscientists Tomás Ryan of Trinity College Dublin and Paul Frankland of the University of Toronto.

‘Memories are stored in ensembles of neurons called ‘engram cells’ and successful recall of these memories involves the reactivation of these ensembles,’ said Dr Ryan.

‘The logical extension of this is that forgetting occurs when engram cells cannot be reactivated,’ he explained.

‘The memories themselves are still there, but if the specific ensembles cannot be activated they can’t be recalled. It’s as if the memories are stored in a safe but you can’t remember the code to unlock it.’

Forgetting, the team have proposed, occurs when engram cells are switched from an accessible to an inaccessible state — locking away the memories.

‘Because the rate of forgetting is impacted by environmental conditions, we propose that forgetting is actually a form of learning that alters memory accessibility in line with the environment and how predictable it is,’ Dr Ryan continued.

Dr Frankland agreed, adding: ‘There are multiple ways in which our brains forget, but all of them act to make the engram — the physical embodiment of a memory —  harder to access.’ 

When we forget, said paper author and neuroscientist Tomás Ryan, ‘the memories themselves are still there, but if the specific ensembles cannot be activated they can’t be recalled. It’s as if the memories are stored in a safe but you can’t remember the code to unlock it’

The findings could help lead to new treatments for pathological forgetting.

‘Importantly, we believe that this “natural forgetting” is reversible in certain circumstances,’ the researchers said.

‘In disease states — such as in people living with Alzheimer’s disease for example — these natural forgetting mechanisms are hijacked.’

This, they explained, ‘results in greatly reduced engram cell accessibility and pathological memory loss.’

The full findings of the study were published in the journal Nature Reviews Neuroscience.

HOW SOON WILL WE BE ABLE TO UPLOAD OUR MINDS TO A COMPUTER?

Brain and memory preservation has been explored at length by futurists, scientists and science fiction junkies alike. 

Many say it falls under the category of ‘transhumanism.’  

Transhumanism is the belief that the human body can evolve beyond its current form with the help of scientists and technology.  

The practice of mind uploading has been promoted by many people, including Ray Kurzweil, Google’s director of engineering, who believes we will be able to upload our entire brains to computers by 2045.

Similar technologies have been depicted in science fiction dramas, ranging from Netflix’s Altered Carbon, to the popular series Black Mirror.  

Another prominent futurist, Dr Michio Kaku, believes virtual reality can be used to keep our loved ones’ personalities and memories alive even after they die. 

Scientists and futurists have different theories about how we might be able to preserve the human brain, ranging from uploading our memories to a computer to Nectome’s high-tech embalming process, which can keep it intact for thousands of years

‘Imagine being able to speak to your loved one after they die … it is possible if their personality has been downloaded onto a computer as an avatar,’ he explained. 

These ideas haven’t been met without criticism. 

McGill University Neuroscientist Michael Hendricks told MIT that these technologies are a ‘joke.’

‘I hope future people are appalled that in the 21st century, the richest and most comfortable people in history spent their money and resources trying to live forever on the backs of their descendants. I mean, it’s a joke, right? They are cartoon bad guys,’ he said. 

Meanwhile, neuroscientist Miguel Nicolelis said recently that such technologies would be virtually impossible. 

‘The brain is not computable and no engineering can reproduce it,’ he said. 

‘You can have all the computer chips in the world and you won’t create a consciousness.’