December 1, 2021

I, Science

The science magazine of Imperial College

Jai Dongre explains why time flies when you’re having fun and the psychological basis of other temporal illusions. (taken from the latest issue of I,Science magazine)

blue drop Placbo 178545861_3a240300a8_oTime. Physicists define it as the fourth dimension. Philosophers claim it as a conception of the mind. Mathematicians simply know it as t.

Our perception of time has been a significant field of study for psychologists and neurologists alike. Leaving behind the relativistic effects of time dilation, our perception of time in daily life is subject to many factors. Everyone has been in a lecture where time doesn’t seem to pass: the feeling that one of Homer’s great epics could have been recited in what the clock shows to be a couple of minutes. Numerous studies have found that boredom, negative emotions and a lack of motivation increase the perceived duration of time for a certain task. These are called temporal illusions. Just like optical illusions alter what we see from what is really there, temporal illusions alter our idea of how much time has passed.

Temporal illusions are so commonplace that we cease to question their absolute bizarreness. None of our traditional five senses accounts for the perception of time. We do not see time pass, or hear or smell it go by. Our ‘sense’ of time is a crucial part of our brain’s perception of reality, yet we barely notice when it is simply wrong.

For example, time seems to pass faster with age. Even though there are no definitive explanations for this, the theories that have been proposed are quite compelling. One hypothesis is that any given time period for an adult, constitutes a smaller fraction of their life than for a child and so it may seem shorter to them. Another theory, relevant to university life, uses stress as the explanation. Most students know the feeling of not having enough time to do things. Studies by Wittman and Lehnhoff from the University of Munich have shown that people often reinterpret this stress as the feeling that time is passing faster.

Other temporal illusions appear in places you would not expect. A study by Wearden, Todd and Jones at Manchester University found that visual stimuli appeared shorter in duration than auditory stimuli of the same length. It seems that time not only plays a part in the perception of our senses, its effects are also variable.

as time goes by ian rees 14709325044_de371f296b_zAt this point, we must pause to consider whether we could ever have a perfect, or even close to perfect, sense of time. Is it realistic to envisage a day where clocks are not necessary and you always know the precise time? Efforts to improve our senses are well underway. Sight and hearing already have a variety of aids available and touch restoration is already becoming a reality. The future could well hold devices or techniques for perfecting our taste and smell, but could our sense of time ever be fixed if we still haven’t understood how it works? For the moment, at least, it seems that the effects of temporal illusions are here to stay. Our sense of time may be analogous to our sense of direction, and just like GPS technology will often prove our intuition wrong, we may have to continue looking at a clock for an accurate reading of the time. Any way around this can only come in the distant future, after we’ve improved our understanding of how the human brain functions.

Even though we may never see the day when boring family dinners fly by and interesting conversations seem to last forever, our brain’s perception and processing of time is truly fascinating. We should stand in awe, for time is probably the single most essential aspect of our reality, and without it, the world as we know it could never exist.

Jai Dongre is a second year undergraduate studying Biomedical Engineering

Images: Featured image, Escape from Time, captured in an illusion by Henri Louis Hirschfeld; Blue drop by Placbo; As Time Goes By by Ian Rees