Yesterday we went to the town centre by
bus. When we reached near the bus stand our bus was just leaving. Next bus came
in 3 minutes as scheduled. But it seemed that we waited much longer. When coming back we reached the bus station
early. The bus was due in 30 minutes. Thought of going to Starbuck for coffee
but it seemed that there was not enough time. We just waited at the bus
station. It came on time and we reached back home.
Strangely, 3 minutes wait seemed much
longer at our local bus stand whereas it certainly seemed less than half an
hour while waiting at the city centre. Was it because there was much more
activity at the main bus station to keep our attention diverted compared to our
local road side bus stand or was it that we were more eager to go to town
centre than coming come?
But this phenomenon of stretching or
shortening of subjective time does happen even for carefully controlled tasks.
A short duration task is overestimated and a long duration task is
underestimated. If someone asks you how long you took to shave this morning,
most likely you will overestimate the duration. On the other hand, if you are
asked how long you took to mow the lawn, you are more likely to underestimate
the duration. It does seem strange but
our subjective time does stretch or constrict with duration of the tasks.
Karl von Vierordt (1868) was first to
put forward this observation academically.
It is known as Vierordt's law. When asked after finishing a task, people
always overestimate the time it took, if the task was of a short duration where
as they underestimated if it took longer. Vierordt’s work was with how people
remembered the duration after they had performed the tasks. It was dismissed as
an error of memory for a long time but recent studies have shown that it happens
even contemporaneously while one is actually performing the task and also in
predicting how long a task would take.
This manipulation of time by our brain is quite
common. We always overestimate the duration of red light at the road crossings
and underestimate the time it takes us to get ready in the morning. So when we
reach late at the office we blame the traffic not our getting up late!
Even if we do not look at a clock, we do
have a sense of time: an inherent internal clock in our brain. Depending on
whether it is running slow or fast our sense of time gets distorted. It has
been shown to tick faster when the energy consumption of the brain is higher
and vice versa.
When you see or hear something unexpected
the brain tries to process it in more detail and that needs more energy. Our
internal chronometer ticks faster and the subjective time is stretched.
When you see a bold coloured or fast moving
picture with loud music in a commercial, it seems that the advertisement lasted
much longer than it really was. With television
time costing a fortune, advertising agencies are getting more adapt at
exploiting our internal clock.
Just the opposite is used by the customer call-centres,
they put soothing low beat classical music while you are waiting. They hope
that customers would feel that waiting time was shorter than what it actually
was. The same technique is employed in the waiting lounges at railway stations
and airports.
We all have a few friends who always
turn-up late. Now we know they are not intentionally adhering to Indian
Standard Time but their internal chronometer is set at a slower pace!
The concept of duality of time is of course
not new. Ancient Indian philosophers called it Kaal and Ritu. The former is abstract,
universal, running always at the same pace. The later is subjective, variable
and perceivable. Kaal is reality; Ritu is manifest or percept.
