We Will Forget Much of the Pandemic. That’s a Good Thing.

This article is part of Times Opinion’s reflection on the two-year mark of the Covid pandemic. Read more in a note from Alexandra Sifferlin, Opinion’s health and science editor, in our Opinion Today newsletter.

As we approach another anniversary of the pandemic’s onset, many of us are reflecting on the past two years and thinking about the ways the virus has altered our lives. More than 950,000 Americans have died. Many more have lost a loved one, and millions are still grappling with the lingering aftereffects of infection.

As we begin to move toward a postpandemic future, it is vital that we remember the toll this virus has taken. The lessons of this pandemic should be carried with us so that — unlike what happened after the 1918 flu — it doesn’t fade from history and so we can honor and memorialize those we have lost.

It is also inevitable that over time, many of our memories of these difficult years will fade. As a neuroscientist who studies memory and memory disorders like Alzheimer’s, I find this fact — perhaps counterintuitively — comforting. I have come to understand, through new research, that there is a danger in remembering too much and that forgetting is not only normal but in fact necessary for our mental health.

It used to be thought that forgetting anything — from minor things like the name of a casual acquaintance to the more painful loss of cherished memories experienced by my patients — was caused, to varying degrees, by a failure of the brain’s memory mechanisms. But new developments in neuroscience over the past decade or so refute this simple idea.

Neurons contain what are sometimes called nanomachines that are dedicated to the construction of new memories. But scientists have recently discovered that neurons are also endowed with a completely different set of nanomachines designed for the opposite purpose: to carefully disassemble — and thus forget — components of our stored memories.

In light of this new and growing body of research, normal, everyday forgetting can no longer be thought of as a malfunction of our memory machinery; instead it should be considered a healthy and adaptive part of our brain’s normal functioning. Memory and forgetting work in unison. We depend on our memory to record, to learn and to recall, and we depend on forgetting to countervail, to sculpt and to squelch our memories. This balancing act is, as it turns out, vital for our cognitive functioning, creativity and mental health.

Of course, there are unhealthy kinds of forgetting. Alzheimer’s disease, for one, targets memory mechanisms and causes them to fail. But in other disorders, it appears that the brain’s forgetting mechanisms break down. The psychological condition that perhaps best exemplifies what can happen when people don’t forget properly is PTSD. While it is often beneficial to remember the facts of a traumatic experience, sometimes even in pointillist detail, it is equally — if not more — important to the healing process to let the emotional valence of it fade. If we don’t, we can get stuck in total emotional recall, reviving our distress in perpetuity.

Forgetting protects us from this debilitating anxiety not by deleting memories but by quieting their emotional scream. The same is true for more run-of-the-mill emotions. Intuitively, it makes sense that we sometimes need to let go of hurt and resentment to preserve close friendships and that we need to forget in order to forgive. “Letting go” is just one of the many colloquialisms that implicitly nod in recognition and gratitude toward our brain’s forgetting mechanisms.

In patients with PTSD, the area of the brain that stores fear memories is highly active, suggesting that the individual cannot properly engage the brain’s fear forgetting system and therefore cannot let go of the high anxiety associated with the memory of the traumatic event. Complex disorders should not be oversimplified, but it is possible to think about PTSD as a disorder stemming from too much memory, caused by an inability to forget a traumatic experience in a healthy way.

Turning down activity in this brain region effectively induces a healthy ability to forget feelings of fear. Drugs like MDMA do just that and are being tested as a treatment for PTSD. Some couples therapists have even used MDMA to accelerate the forgetting and forgiving process in their patients. From the testimonials of recreational users, quieting fear-related memories is apparently so potent in its prosocial effects — making people friendlier, more compassionate, even more loving — that it underscores how unchecked fear memories can make people antisocial and miserable.

Of course, we won’t — and shouldn’t — forget the pandemic. In addition to memorializing the loss of our loved ones, we should commemorate the selfless commitment of our health care workers and rewrite our government and medical manuals so that we are able to respond better and faster next time. But for many of us, particularly those on the front line, some degree of emotional forgetting will be a natural part of living in and moving forward from the pandemic.

As a society, one of the most beneficial things we can do to move forward in a healthy way will be to resume safe socializing. Several studies have shown that social isolation exacerbates the negative effects of trauma. Because this pandemic required us to socially isolate, we couldn’t make use of the most psychologically beneficial coping mechanism: gathering together.

One of the greatest risk factors for PTSD in troops is when, shortly after trauma, they find themselves socially isolated, their minds exposed without a social fabric to protect them from the lashing loops of their fear and dread. Not every observation about the mind needs a neurological explanation, but it is nevertheless true that socializing causes our brains to secrete chemicals like oxytocin, which — similar to MDMA — induces fear forgetting. Gazing into each other’s eyes is all that is needed for oxytocin to be simultaneously secreted in the gazer and the gazed upon, a feedback loop that induces a socially uplifting pas de deux. Preventing social isolation has become part of the standard of care for those returning from the battlefield and deemed at risk for PTSD.

We can predict that when it’s safe to do so, relaxing the recommendations for social isolation and encouraging people to get together at work, in schools and in other social venues will reduce the risk of long-lasting distress.

With luck, in the months and years ahead, the threat of the virus will abate, and we will be able to let go of the fear that for many of us has been a near-constant companion over the past two years. With hope, the terrifying images of the pandemic’s ravages — the empty streets and crowded hospitals, the funeral pyres and freezer trucks — will cease to loom so large in our collective memory.

Forgetting some of this fear will allow us to more clearly recall the details we want to remember. For me, those include the astonishing resilience, bravery and sense of collective spirit that emerged two years ago this week as my hometown became an epicenter of this pandemic. Those memories make me hopeful for the future.

Scott A. Small is the director of the Alzheimer’s Disease Research Center at Columbia University and the author of the book “Forgetting: The Benefits of Not Remembering.”

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