Prior to the digital era, it was difficult to know what the time was if you woke up during the night. Perhaps, one could turn the light on and have a look at the time on a watch next to the bedside, or an analog clock.

Then digital clocks came along.

By simply opening one’s eyes, or turning over, people could now easily see what the time was during the night. Another example of technology making our lives easier (yes, there was some sarcasm imbedding in that text).

There were even digital clocks that projected the time on the ceiling - making our lives even easier because we didn’t have to roll over to see the time.*

But time and sleep are intertwined.

Whilst we can often base how good our sleep was by how much time has passed since we let go of our surroundings, time is also something that can cause harm to our sleep.

So let’s take a look at some of the interesting science behind clockwatching and sleep.

Selective Attention

During the day, there are alot of stimuli surrounding us - so much so that in order to function, we need to focus our attention on only some of these stimuli. But when day turns to night, there are less stimuli around us. After the sun sets, gradually there are less auditory stimuli to attend to. Light turns to dark, so there are less visual stimuli to see.

So when we go to bed, eventually the last stimuli that >90% see these days is a screen. And it is likely that the screen has the capability of showing the time.

And people differ in how they respond to knowing what the time is.

One such group of people are those who experience insomnia.

For a long time, many people who treat insomnia have heard their patients voice their concerns about ‘time’:

“It takes me a long time to fall asleep”

“I fall asleep very late at night”

“I’m awake alot during the night”

“I wake up earlier than I’d like”

One interesting study set out to scientifically test the effect of clockwatching on sleep, and particularly for those experiencing insomnia.** In this study, people with insomnia were asked to either monitor a clock - or on another occasion - monitor a device that did not tell the time. Thus, they were performing the same behaviour whilst trying to fall asleep, the only difference being whether the device they were monitoring showed the time. And you can probably guess what happened? On the ‘clockwatching’ night, people reported more worry as well as a longer time to fall asleep.

Another study confirmed the importance of time. In this study, people with and without insomnia took part in an experiment during the day. This experiment was essentially a reaction time task, meaning that the researchers were interested in how quickly people responded to different objects. And one of those objects was a clock. In fact, there were multiple clocks, but the interesting thing was the time on the clock. That is, some clocks had a time that occurred at night and others did not. What happened was that people with insomnia lingered longer on clocks that had a night time hour on them. This meant that compared to people who sleep well, people with insomnia have trouble dis-engaging with the time on the clock.

So these studies go to show that not only is a clock somewhat important to people with insomnia, but more importantly, the time-of-night is a huge focus for them.

Whilst some people with sleep problems may benefit from avoiding to look at the clock, this treatment technique alone would not necessarily be potent enough to reduce insomnia in people to the point of them becoming a good sleeper. But it does show how much our society is tied to ‘time’.

If only life was as simple as getting up when the sun rose …

*By the way, we haven’t addressed the light that comes from digital devices, or even those old digital clocks that had blue numbers emanating from them. That’s because we have minimised the effects of the blue light from screens in our other blog here.

**Notice how we’re saying ‘people experiencing insomnia’ and not calling them ‘insomniacs’? Here’s why.