We all have that one person in our lives — a friend, a significant other, or a family member, who's always late. They're habitually late to work, a concert, or even their own birthday party.

So, why can't they be on time like the rest of us? It's all about the perception of time.

Researchers at Washington University in St. Louis, Missouri found the reasons for being late vary with age based on the strategies used to estimate the passage of time.

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“Our results suggest time estimates of tasks that we need to incorporate into our later plans, like a drive to an appointment, are often based on our memory of how long it took us to perform that same drive previously,” said Emily Waldum, principal author of the paper and a postdoctoral researcher in psychological and brain sciences in Arts & Sciences, in a statement.

Previous research has shown how simply hearing music meddles our relationship with everyday time. For example, we're more likely to spend 38 percent more time in the grocery store when the background music is slow. The music in the background begins to act as "subjective time," meaning our perception of time is distorted based on external factors, like a song. We may underestimate how long we spend grocery shopping if we rely on the song we hear as our time guide.

In other words, our perception of time elapsed is influenced by our "prospective memory." Psychologists use this to describe the process of remembering to do something in the future.

In the study, published in the Journal of Experimental Psychology: General, researchers sought to examine the differences in how people young and old approach a task that requires them to plan ahead, and complete a series of time-based tasks by a specific deadline. It aimed to replicate the time-based prospective memory challenges people experience in everyday life. A total of 36 college undergraduates and 34 healthy older adults in their 60s, 70s and 80s were part of the challenge.

First, participants were asked to keep track of how long it took to complete a trivia quiz. The quiz ran for 11 minutes, but participants had to make their own time estimates without looking at a clock. Some participants completed the quiz with no background noise, while others heard either two long songs or four short songs. Shortly after, researchers challenged the participants to put together as many pieces of a puzzle as possible while leaving enough time to complete the same quiz before a 20-minute deadline.

The findings revealed seniors completed future tasks on time at about the same rate as college undergraduates. However, both groups used different strategies to estimate how much time they would need to repeat the quiz, and finish the next portion of the challenge by the deadline.

Rather than using the songs in the background to tell time, older adults relied on an internal clock to estimate how long it took them to complete the first quiz. Seniors tended to underestimate time taken on the first quiz, which led them to spend a little too much time on the puzzle, and finish the second quiz a bit beyond deadline. In the second part of the study, when a clock was made available, they were less likely to pause working on the puzzle and quiz to check the clock.

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Seniors may have the tendency to over-rely on their internal clocks, which gives them a feeling of elapsed time. However, checking a clock when it's available is a much better strategy than relying on elapsed time. Therefore, the more likely we do clock checks, the better our time-based prospective memory performance.

Meanwhile, when young adults heard two long songs during the first quiz, they performed a lot like older adults, meaning they underestimated the quiz duration and wound up a bit late. However, when they heard four short songs, young adults overestimated how much time they would need to repeat the quiz, which led them to finish it too early. Unlike older adults, background music played a big role in whether young adults were too early or too late.

The researchers noted tricks we use to stay on schedule could evolve as we age. For example, in college students, using songs to estimate the passage of time could be a plausible effort when no clock is available.

Using a TV show as an indicator of time could also be a good time hack.

“In a scenario where the duration of a background event is set, such as a 30-minute television show, this is a very good strategy because it provides useful duration information whether you’re paying attention to the show or not,” said Waldum.

Using songs and other events as a time estimate can be risky, and unreliable. Clock checking could require us to diverge our eyes elsewhere, but it could save us time in the long run.

"Our results, while preliminary, suggest that time-management ability and the ability to perform some types of complex time-based tasks in real life may largely be preserved with age," said Waldum.

We often underestimate how long it can take to complete required tasks. Building extra time into our plan could help us improve our timeliness. Waldum and her colleagues suggest stopping a task midstream to avoid getting sucked in by tasks. For example, we may opt to answer one more email, but this will not help us get to our destination on time. We're also more likely to immerse ourselves in one activity, and not move on with the next. Lastly, we should avoid distractions. If we leave our office on time, but spend the next 10 minutes talking to our neighbor, we're not doing anything to help our schedule.

It’s easy to get sidetracked with things in the moment that could be more appealing and engaging than arriving to an appointment on time, but if we understand what makes us late, we can counteract it in the future.

Source: Waldum ER and McDaniel MA. Why are you late? Investigating the role of time management in time-based prospective memory. Journal of Experimental Psychology: General. 2016.

See Also:

New Study Shows How Time Perception Varies Across Species

Circadian Rhythms, Clock Genes In Brain Regions Influence Perception Of Time