Does time seem to fly by, move slowly or move just right—or all of these variations? Actually, time doesn’t change, but our perception of it does and that can affect our lives—maybe this pearl can give some insight as to why.
It seems that when we are young time moves very slowly and we can’t wait to be older. As we become seniors, time moves very quickly and we yearn to be younger. For comic relief on this subject you might enjoy the late George Carlin’s pleasant take on our perception of time as we age (he lived to be 102). Go to: https://www.youtube.com/watch?v=-5s6FLjdZNc
Our perceptions of time vary throughout the day, whether at work, home or play. Time progresses slowly when we are anticipating an exciting future event and time progress faster the busier we are. This applies whether we have a weak or strong work ethic (preferring to be busy with tasks). Our busyness is what we typically think about in the progression of time, but this is not what this pearl is about.
Definitions:
First, the definition of an interval is: “the amount of time between two specified instants, events, or states”.
Using this definition of interval, the definition of time, which is quite long and complicated, can be reduced to: “the interval between events in our lives”, whether in seconds, days or years. Time progresses equally for everybody, but as we age (especially as seniors) there is a noticeable decrease in the interval between events, making the events move by faster, sometimes dangerously fast. The antithesis of this is when time moves much slower, making the interval between events seem interminable.
Our final definition is perception (perceiving), which is: “to become aware of, directly through the senses, especially sight or hearing”. But our senses can deceive us, especially when we are not consciously aware of our surroundings, like when we are sleepy or concentrating on something like a task, book, movie, etc.
When our Perception of Time Slows Down:
The catalyst for this phenomenon is the level of the neurotransmitter “norepinephrine” (also called “noradrenalin”) in the brain. The more norepinephrine in the brain the faster it processes its sensory input by making those neurons fire faster than normal. This lengthens the perceived interval between events, thus making the events seem to move by slower. A physical example might help: our oscillating eyes provide our visual cortex with a new scan every 50 ms (milliseconds) or about 20 scans per second. When our brain has its normal level of norepinephrine it processes those 20 scans every second. But if the brain’s norepinephrine level doubles it can double the brains processing speed, processing those 20 scans in only say, half a second. This makes the perceived interval between scans seem twice as long (from two processings instead of one, when we are use to just one) and thus things move half as fast. This is similar to filming a slow-motion movie segment—the high-speed camera takes twice as many pictures per second, but when played back they move at half the speed—in slow motion.
Norepinephrine is associated with the fear emotion and the more terrifying the situation the higher the level of norepinephrine in the brain and the longer the perceived interval between events creating a perceived slowing of time. Most of us have experienced this slow-motion phenomenon—I have numerous times. One day in the botanical gardens I observed my 4-year-old daughter from a distance tumbling down a flight of wide stone steps towards a deep pond. The terror I sensed made my brain process that event much faster, perceiving her tumbling down each step in slow motion—it seemed to never end—I was too paralyzed to even move. Luckily, she didn’t end up in the water and wasn’t too badly bruised, but very upset.
When our Perception of Time Speeds Up:
Research indicates that the older we get the lower our brain’s level of norepinephrine, making the brain process sensory input slower, shortening our perception of the interval of time between events, thus making them move by faster. For example, when younger we can lay awake in bed for minutes before falling asleep and an 8-hour night’s sleep can be attained in about eight hours. As seniors those minutes can turn into hours before falling asleep, but we still think it was only minutes (unless we glance at a clock). This is why we can spend eight or ten hours in bed and get only six or seven hours of actual sleep. Driving a car is a better example of time speeding up by the shortening the perceived interval between events due to lower norepinephrine levels.
While driving for decades we tend to glance around at things and then look forward, instinctively knowing how much time has passed. While driving at a constant speed we know that a car that is 100 feet in front of us when we glance away will still be 100 feet away when we look forward again. This is not the case as we age. The perceived interval between events gets shorter making time move faster and thus, the car that was 100 feet away when we glanced away will only be about 50 feet away when we look forward again. We seem to get this same affect when driving under the influence or suffering from Alzheimer’s disease.
The point is that if we are not aware of this phenomenon we may end up dangerously close to the cars in front of us or more likely, drift out of our driving lane into cars in adjoining lanes or off of the road entirely. This realization creeps up on us as we age, until we become aware that it is dangerous to glance sideways for too long without making a conscious effort to quickly look forward again before we get into trouble. If not yet aware of this phenomenon, it is something to keep in mind to be safe. And if you or a family driver is up there in age, it may be best for the driver to keep twice the usual distance between your car and the ones in front of you and try to hold the stearing wheel in place.
But, Moving Onward:
Another consideration in the shortening of time is Albert Einstein’s “Special Theory of Relativity”, but since we don’t usually drive near the speed of light it need not be considered in this discussion. But it does provide us with a segue to the next two pearls in this 3-part series about time, matter and the forces of nature.
If one seeks, they will find parallels between astrophysics and orthodontics. Besides having four syllables each, they both deal with space-time (the time it takes to close spaces), accelerating masses (moving teeth through bone) and, the forces of nature (light wire forces and gravity or strong RPE forces and nuclear or electromagnetic forces). Since orthodontists are essentially scientists, I figured that a brief vacation from the forces of orthodontics to the forces of nature and the cosmos might be refreshing. I hope that you think so too!
