Why
does time seem to move quicker as we age?
Duke
University
Photo by Will Collette |
According
to Adrian Bejan, the J.A. Jones Professor of Mechanical Engineering at Duke,
this apparent temporal discrepancy can be blamed on the ever-slowing speed at
which images are obtained and processed by the human brain as the body ages.
The
theory was published online on March 18 in the journal European Review.
"People
are often amazed at how much they remember from days that seemed to last
forever in their youth," said Bejan.
"It's
not that their experiences were much deeper or more meaningful, it's just that
they were being processed in rapid fire."
Bejan
attributes this phenomenon to physical changes in the aging human body.
As tangled webs of nerves and neurons mature, they grow in size and complexity, leading to longer paths for signals to traverse.
As
those paths then begin to age, they also degrade, giving more resistance to the
flow of electrical signals.
These
phenomena cause the rate at which new mental images are acquired and processed
to decrease with age.
This
is evidenced by how often the eyes of infants move compared to adults, noted
Bejan -- because infants process images faster than adults, their eyes move
more often, acquiring and integrating more information.
The
end result is that, because older people are viewing fewer new images in the
same amount of actual time, it seems to them as though time is passing more
quickly.
"The
human mind senses time changing when the perceived images change," said
Bejan.
"The
present is different from the past because the mental viewing has changed, not
because somebody's clock rings. Days seemed to last longer in your youth
because the young mind receives more images during one day than the same mind
in old age."