But how does this explain the continuing shortening of perceived time as we age? The theory goes that the older we get, the more familiar we become with our surroundings. We don’t notice the detailed environments of our homes and workplaces. For children, however, the world is an often unfamiliar place filled with new experiences to engage with. This means children must dedicate significantly more brain power re-configuring their mental ideas of the outside world. The theory suggests that this appears to make time run more slowly for children than for adults stuck in a routine.
So the more familiar we become with the day-to-day experiences of life, the faster time seems to run, and generally, this familiarity increases with age. The biochemical mechanism behind this theory has been suggested to be the release of the neurotransmitter dopamine upon the perception of novel stimuli helping us to learn to measure time. Beyond the age of 20 and continuing into old age, dopamine levels drop making time appear to run faster.
But neither of these theories seem to tie in precisely with the almost mathematical and continual rate of acceleration of time.
The apparent reduction of the length of a fixed period as we age suggests a “logarithmic scale” to time. Logarithmic scales are used instead of traditional linear scales when measuring earthquakes or sound. Because the quantities we measure can vary to such huge degrees, we need a wider ranging measurement scale to really make sense of what is happening. The same is true of time.
On the logarithmic Richter Scale (for earthquakes) an increase from a magnitude ten to 11 doesn’t correspond to an increase in ground movement of 10% as it would do in a linear scale. Each increment on the Richter scale corresponds to a ten-fold increase in movement.