Sorry I'm late, it's all down to my chronobiology
Individuals differ in terms of their chronotype – that is to say whether you are morning oriented or evening oriented, or somewhere in the middle
We are well into party season as the holidays approach, with dinners, drinks with friends and similar festive cheer. But in the midst of all the fun there is also an annoyance: the latecomer.
Everyone knows someone who is always late. Maybe you’re one of those people yourself. Theories on why some individuals are late on a regular basis come from a variety of perspectives – anthropological, cultural, neurological and psychological. But are there scientific explanations for chronic lateness?
We are all governed by our circadian clocks. The study of this internal clock comes under the heading of chronobiology. “Circadian rhythms are internal 24-hour rhythms created by the Earth spinning on its axis within a 24-hour period,” says Dr Andrew Coogan, a chronobiologist at NUI Maynooth.
“Life has evolved to take advantage of that. Through evolution we have adapted a time-keeping mechanism. Animals and organisms can anticipate changes in their environment and then react appropriately. It’s important particularly for preyed-upon animals, who know to get home before it’s dark.”
The existence of circadian rhythms was first demonstrated in the 1960s when human subjects were placed into a timeless environment – a concealed former second World War bunker to be exact – with no time-reference points, clocks, natural light and so on.
It was found that the volunteers still expressed 24-hour rhythms through their internal clock. They had energy at appropriate times, slept at night time and were awake during the day.
But circadian rhythms affect individuals differently and can lead to inclinations towards “morningness” or “eveningness” and, in turn, “lateness”.
“Individuals differ in terms of their chronotype – that is to say whether you are morning oriented or evening oriented, or somewhere in the middle,” says Coogan.
“This is both an individual characteristic but also changes across the lifespan so small children generally are morning oriented, teenagers tend towards eveningness, then back towards the morning in adulthood.
“This affects the time of day we are most alert and our cognitive prowess is best set up for. Such individual differences seem to be down in part to genetics, but may also be driven by environmental factors – TVs, computers in bedrooms and street lighting at night might all make for a tendency toward ‘eveningness’.
“It might also explain in part lateness. If you are trying to get out of bed and get to school early yet your body clock is not attuned to that rhythm you may struggle and end up being late. So some of us may be predisposed to be late at different times of the day – probably most pertinent to the morning.”
The inclination towards morningness and eveningness also relates to personality. Eveningness tends to be associated with creativity and impulsiveness.
“Plus if you’re a strongly creative person you lose a sense of time when you’re in the middle of something you find very interesting – otherwise known as the absent-minded professor effect,” says Billy O’Connor, professor of physiology in the Graduate Entry Medical School in the University of Limerick.