Why we need a witness to remember

Loneliness doesn't accelerate memory loss. It just means you start with less.

A major seven-year European study published in Aging & Mental Health in 2026 tracked 10,217 adults aged 65 to 94 across 12 countries and found that loneliness was associated with significantly lower baseline memory scores.

Lead author Dr Luis Carlos Venegas-Sanabria of the Universidad del Rosario said:

“The finding that loneliness significantly impacted memory, but not the speed of decline in memory over time, was a surprising outcome. It suggests that loneliness may play a more prominent role in the initial state of memory than in its progressive decline.”

Think of it as beginning a race several hundred metres behind everyone else. You might run at the same pace, but you are unlikely to ever catch up to the pack.

This finding invites a deeper question: what happens to a human being when they no longer have a witness to their life? Our brains are not solitary computers processing data in a vacuum. They are social organs, evolved over millennia to navigate the complex terrain of human relationships.

Robin Dunbar, an evolutionary psychologist at the University of Oxford who has spent thirty years developing his Social Brain Hypothesis, puts it plainly:

“Why do primates have such big brains? Well, it must have to do with the fact they live in very large, complicated societies. They need a big computer to manage all the relationships.”

When we remove that social stimulus, it is as if a vital piece of hardware is left to idle. Without the regular workout of conversation, empathy, and shared storytelling, our cognitive reserve begins to thin.

There is also the physiological toll. A 2023 review in Brain, Behaviour and Immunity found that chronic loneliness activates stress-response pathways, elevates cortisol, and promotes systemic inflammation. The hippocampus, the region critical for forming new memories, is particularly vulnerable to these changes. In a very real sense, the Archipelago of the Self is a difficult place to maintain a healthy mind.

Then there is the “chicken or egg” problem. Does loneliness cause memory loss, or does the early, silent onset of cognitive decline cause us to withdraw? If socialising becomes more taxing because we cannot quite grasp the right word or remember the thread of a story, we often choose the safety of solitude over the risk of embarrassment.

But there is hope. Dr. Venegas-Sanabria concluded that his findings

“underscore the importance of addressing loneliness as a significant factor in the context of cognitive performance in older adults.”

If memory scores are lower due to baseline loneliness, social connection is not a nice extra. It is a foundational requirement.

We talk about brain-training apps or crosswords as paths to a sharper mind (I do my Wordle every day!). Yet as Dunbar puts it, “All you have to do is go and spend a bit of time with your friends.”

Our memories are not just private archives. They are shared treasures. When we choose to relate well to others, we are not just being “good humans.” We are quite literally keeping our minds alive.

How different would our lives look if we treated social connection with the same clinical importance as our blood pressure or our diet?