The Real Reason Time Seems To Move Faster As You Age

After Albert Einstein published the theory of relativity, he and his secretaries were constantly bombarded by news outlets looking for a soundbite that would explain this world-shaking idea to those of us without physics diplomas. Einstein briefed his team with the following quote: "When you sit with a nice girl for two hours you think it's only a minute, but when you sit on a hot stove for a minute you think it's two hours. That's relativity." (via Quote Investigator)

We are all inherently aware that time in subjective. You probably first noticed in school; that one particular semester felt shorter than the last one. In fact, when you came to think about it, you might also have realized that this whole school year seemed to have gone by in a flash compared to the last one. You may have shaken it off as an aberration, but then, as time went on, you began to realize that each and every school year seemed thinner than the last, that the last day before summer came around faster and faster each year.

In his memoir, "Summer of a Dormouse," written at the age of 75, the author John Mortimer noted: "In childhood, the afternoons spread out for years. For the old, the years flicker past like the briefest of afternoons. The playwright Christopher Fry, now ninety-three, told me that after the age of eighty you seem to be having breakfast every five minutes."

That time speeds up as we get older has been widely observed, but can science tell us why?

The speed of time in proportion to memory

Some of the most common explanations concerning why time seems to speed up as we age are tied to memory, and, like memory, such explanations tend to be frustratingly fuzzy. 

As noted by Psychology Today, one theory goes that our perception of time's passing is inherently linked to the years we have lived inasmuch as the elder among us have a deeper bank of memories to draw upon.

To a five-year-old child, a single year feels incredibly long as it represents 20% of their life so far — more if we discount their infancy, which might not be remembered. To a person in old age, however, a year is a tiny fraction of the life they have lived.

This proportional explanation is somewhat satisfying in giving a rule-of-thumb as to how fast time might seem to be passing at different ages, but when we think about it, it still doesn't quite touch on why. Thankfully, however, experts in the fields of psychics and biology are increasingly trying to nail down the phenomenon in scientific terms.

A neural explanation

Writing for Psychology Today, Clifford N. Lazarus Ph.D explains a common experiment, in which both small children and older adults are asked to try and estimate unaided the passing of a single minute. According to Lazarus, children tend to vastly overestimate the passing of time, often guessing that a minute has passed within just 40 seconds. In contrast, adults often perceive a minute has passed at the 70-second mark.

Scientists have postulated that this disparity of time perception may be the result of the gradual slowing of the "neural pacemaker" of the brain. In childhood, the brain processes a greater number of images — Lazarus makes the comparison to a film camera rolling at a higher framerate per second — but like the heart, the beating of which slows as we age, the process of neurovisual memory-making becomes slower-paced, meaning that time appears to pass more quickly.

Lazarus points to a 2019 paper by Professor Adrian Bejan, published in the European Review, which describes how more "actual time" passes between the arrival of each newly-created neural image. Bejan presents a series of scientific models which suggest the "​​perceived misalignment between mental-image time and clock time" in physics might be reflected in our common everyday perception that, yes, the slowing down of our neural processes might explain why those long summer months seem to become evermore shorter as the years roll on.