Part One: The Study of Time Perception
Here’s an interesting thought experiment that shows how you could theoretically live forever. Here we’re going to imagine that you have the ability to speed up your brain’s processing by running an electric current through it. As you do that, you find that all your senses light up and your thoughts become faster causing everything around you to appear as though it’s moving at a snail’s pace. You’re taking in twice the information and making sense of it all twice as fast, so everything else seems incredibly slow in comparison. Likewise the number of thoughts you can have in a minute doubles, which makes that minute subjectively appear to pass twice as slowly as it is twice as ‘full’.
Now in this imaginary scenario, you find that every time you increase the voltage, your brain speeds up by double the amount again.
So if you were currently thinking one word per millisecond and you turned the voltage up, you would be able to think at two words per millisecond. Now turn the voltage up again one millisecond later and you’re thinking at four milliseconds per second. Each time you do this, a second stretches even further and you never seem to reach the ticking of the clock.
In theory you will live for what seems like an eternity, but all within the span of a single millisecond.
So you see as far as we’re concerned, it’s not really how long we live, or how much time we have that matters – rather it’s our very subjective perception of that time that will make all the difference to us. We’re going to go quite deep now into the brain’s perception of time – it’s a lot to read but stick with it because it has some amazing implications. We’ll find out why you actually lose 40 minutes of every day for instance and look at people who have experienced years’ worth of existence in the space of a few minutes…
The Study of Time Perception
Unfortunately a ‘Bernard’s Watch’ type device to speed up our brain and stop time has not yet been invented, but there’s no reason to think that something like this would be impossible – it’s just a matter of unravelling how the brain perceives time.
Thus the study of time perception is a fascinating one and one that is hotly discussed within the scientific community.
What psychologists are looking at here is what’s known as ‘perceived duration’, which is the perceived time interval between two events. What’s particularly fascinating is that perceived duration is not thought to be the same for everyone – so one person might experience a second as being slightly longer than another person, and as such would potentially effectively ‘live’ twice as long in terms of their subjective perspective. Even without any electric shocks, a person’s perception of time has been demonstrated to be susceptible to manipulation.
It’s interesting to note that dreams will often seem to occur over much longer periods of time than they in fact do, as can trips on psychedelics. There also appear to be significant differences between species of animals.
Models of Time Perception
In the study of time perception there are two popular models that are used to explain how the process may work. The ‘strength model’ suggests that the brain uses a ‘memory trace’ in order to judge the age of a memory and thereby how long ago that memory might have occurred.
The inference model meanwhile suggests that the time of any event is merely inferred from contextual information attached to that memory – such as where it took place, how long ago it was, or how youthful you remember being at the time. This model could potentially explain in part why dreams are difficult to gauge the duration of (as the context is fantastical) and why we struggle to remember details such as what we ate on a particular night.
Brain Regions
Particular brain regions have been linked with our perception of time by research and theories. It is believed that the effect takes place through a ‘distributed’ network of brain regions throughout the brain which involve the cerebral cortex, the cerebellum and the basal ganglia.
The suprachiasmatic nucleus is well-known meanwhile for controlling our body clock or ‘circadian rhythm’. Other cells are believed to control our ‘ultradian’ rhythm which is any rhythm that takes place over the course of a single day or shorter. A common example of our ‘ultradian’ rhythms are during sleep, during which time the brain will cycle through various stages. Other ultradian rhythms include things like blinking, circulation and heart rate.
Part Two: Temporal Illusions
In part one we looked at the study of time perception and discussed why it was interesting and how we think it might work. We also mentioned that it was possible under a number of circumstances to ‘fool’ the brain into perceiving the passage of time as going more slowly or more quickly, which is one of the ways in which we can study the subjective perception of time.
Here we will look at a number of these illusions, which can shed some fascinating light on our brain and its understanding of time…
Vierordt’s Law: This law describes the tendency we all have to judge short intervals as being overly long, and long intervals as being overly short.
Auditory vs Visual Stimuli: It appears that auditory stimuli appear to last slightly longer when compared with visual stimuli – possibly due to differences in our processing speeds.
Intensity: Stimuli of greater intensity (volume, brightness etc.) appear to last longer than those with less intensity. Possibly due to prolonged excitation of nerves.
The Kappa Effect: The Kappa Effect states that we judge consecutive events as taking longer when you increase the amount of time between the two events. If you make a journey in two parts and take a break to rest in-between, then you will often feel as though you spent more time travelling if you spend more time resting in between.
Stopped Clock Illusion: A ‘saccad’ describes the quick movements our eyeballs make when we look from one thing to another. These saccads create a slight blur as we look from one thing to another – which our brain doesn’t have any use for. Thus our brain will erase that information from our memory, essentially skipping us forward in time as far as our brain is concerned.
So you have this empty fraction of a second to account for, what does the brain do about that? Simple – it fills that second with the thing you changed your gaze to. This is where the ‘stopped clock’ illusion comes from: when you quickly glance at a clock’s second hand and that first second appears to take slightly longer than all the rest. This effect is also known as ‘chronostasis’ and it also effects other senses – such as when you move a ringing phone from one ear to the other (try it!).
Now are you ready to have your mind blown? All those little fractions of a second that you lose actually add up to around 40 minutes each day. That’s 40 minutes of time that is simply ‘lost’. Now how reliable does your time perception feel?
The Oddball Effect: Many of us are familiar with the concept of time slowing down when we’re in some kind of danger. For instance our perception of time is thought to slow down while sky diving, when fighting or when scared.
There are two explanations for this. One is that the release of adrenaline which speeds up our metabolism results in a kind of ‘time dilation’ with the obvious advantage of helping us to react more quickly. At the same time adrenaline also encourages us to focus more on the subject which also seems to give us a few extra seconds to react.
Another theory though is that our perception of time actually doesn’t alter at all during such events. Rather it is suggested that it’s actually our memories of those events which is affected. The theory goes that we in fact assign great importance to these events and thus our brain naturally records them in greater detail resulting in content and the perception that those events must have taken longer.
Draw your own conclusions, but for me the first explanation holds more water as I’ve pulled off some pretty incredible feats of catching things when surprise sets off my adrenaline that I otherwise wouldn’t be able to achieve.
Emotions and Time Perception
Many studies have shown that different emotions appear to alter the way we judge the passing of time, with studies showing that watching scary films makes time appear to have passed slower in retrospect. This is again likely to do with the release of arousal-promoting hormones in the amygdala which appears to increase the metabolism and thus the rate of internal clocks and which may help us lay down more memories.
This seems contrary however to the fact that time appears to go so slowly when we’re bored or not doing anything. What’s happening here though is that the lack of something engaging to focus on leads to your brain looking around for distractions. Thus you are actually doing more sensory processing and taking in more information which creates the illusion that more time is passing. Add in all the gaps between finding things to look at or think about (the kappa effect) and you have extended the illusion further.
What’s interesting is that while it seems like forever when you’re standing in a queue, it’s quickly forgotten afterwards. That’s because your brain doesn’t really store much of the boring information that came in during that time, so it seems like comparatively little happened and actually the passage of time must have been shorter.
Why Time Speeds up as We Age
One illusion of time perception that you may have noticed yourself is that of time ‘speeding up’ as you get older. Think about the duration between the ages of 13-14 versus the time that seemed to pass between 30 and 31. A year used to seem like a lifetime back then and now it’s going at a brisk pace.
This is partly due to the comparative length of those years in comparison to all the other information stored in your brain. One year when you were 13 was 1/13th of your life, whereas at 30 it’s only 1/30th. Thus it is a comparatively shorter amount of time.
The other thing to remember is that you take in less novel and interesting new information as you get older, which means less of that data gets ‘saved’ in your brain. The more routine your life becomes, the less information will get added to the stockpile and the more briskly it will seem to pass you by.
Drugs and Time Perception
The most extreme examples of time perception alteration however are those involving psychoactive drugs such as LSD and Ketamine. These can cause time to apparently speed up, slow down, or just appear out of sequence (stories involve people asking friends for the time and being told completely random answers). On a BBC documentary, the British MP used mescaline hydrochloride under controlled conditions and described experiencing a ‘period of time that didn’t end’. These seem to support the ideas put forward by the ‘strength model’ of time perception – showing that we may potentially put a kind of ‘time stamp’ on our memories (which may also explain deja vu).
The underlying mechanics of this effect are not fully understood, but studies have demonstrated that the drug psilocybin can impair the ability of participants to estimate time periods or to ‘tap along’ with beats. Stimulants meanwhile reliably cause us to overestimate timespans, while depressants have the opposite effect.
Other brain-states can meanwhile have similar effects, such as meditation, such as fever and such as dreaming. In dreams sequences can seem to span long periods of time, largely due to the ‘compressed storytelling’ nature of some of those dreams. Mindfulness meditation meanwhile trains the brain to be ‘present’ which results in more information taken in.
Other Variables and Conclusions
Countless other variables have also been shown to influence our perception of time passing. Being cold for instance has been shown to make time pass seemingly more slowly, while being hot has the reverse effect (again this is probably due to the increase in heart rate that comes with being cold) and thus the ‘faster’ rate of the body and mind. Similarly we have been shown to be slower and to thus perceive time as passing more quickly as we become more tired (possibly why the last hour or two at work tend to rush by).
There’s much more to explore here and it truly is a fascinating topic. For now you shouldn’t expect to reach the point where you can pause time and have complex thoughts before dodging a punch, and nor should you hope to be able to freeze time in exams to come up with perfect answers to questions.
What we do know is that our perception of time is largely an illusion with many flaws that is created by our brain. We also know that emotion, metabolism and attention increase the perceived timespan which seems to relate very closely to the number of processes our brain can carry out in that time. If you want to get more out of your time on Earth then you should increase your fitness and your presence of mind, keep seeking out new and stimulating activities and take in everything around you.