How a clock measures time and how you perceive it are quite different. As we grow older, it can often feel like time goes by faster and faster. This speeding up of subjective time with age is well documented by psychologists, but there is no consensus on the cause. In a paper published this month, Professor Adrian Bejan presents an argument based on the physics of neural signal processing. He hypothesizes that, over time, the rate at which we process visual information slows down, and this is what makes time ‘speed up’ as we grow older.
As we age, he argues, the size and complexity of the networks of neurons in our brains increases – electrical signals must traverse greater distances and thus signal processing takes more time. Moreover, ageing causes our nerves to accumulate damage that provides resistance to the flow of electric signals, further slowing processing time. Focusing on visual perception, Bejan posits that slower processing times result in us perceiving fewer ‘frames-per-second’ – more actual time passes between the perception of each new mental image. This is what leads to time passing more rapidly.When we are young, each second of actual time is packed with many more mental images. Like a slow-motion camera that captures thousands of images per second, time appears to pass more slowly.
As he puts it: “People are often amazed at how much they remember from days that seemed to last forever in their youth. It’s not that their experiences were much deeper or more meaningful, it’s just that they were being processed in rapid fire.”
Bejan’s argument is intuitive and based on simple principles of physics and biology. As such, it is a compelling explanation for this common phenomenon. However, it is not the only explanation out there, and so a more rigorous experimental approach may be required before this mystery is solved for good.
Managing Correspondent: Rory Maizels
Original article: Why the Days Seem Shorter as We Get Older – European Review
Media coverage: It’s spring already? Physics explains why time flies as we age – Science Daily; Physics explains why time passes faster as you age – Quartz
Image Credit: Aron Visuals