We've all had that one dinner with dear friends that passes by us in an instant, or that impending feeling of boredom that comes with 'having too much time on our hands'.
Time can race, it can slow or it can screech to a grinding halt. It all comes down to how we perceive it -- and our state of mind.
When we are concentrating on the duration of an event, time seems to pass inexorably more slowly than normal, in line with the phrase 'a watched pot never boils'.
"Our perception of time can be strongly influenced by our current level of focus, physical state and mood," Dr Muireann Irish, Senior Research Officer at Neuroscience Research Australia told The Huffington Post Australia.
Let's break it down for you.
'Real' time versus perceived time
Whilst it is hardly disputed that one minute is made up of 60 seconds, our perception of what this time feels like can vary.
Going up against the clocks and calendars that make up 'real time', Dr Irish says humans use predictable repeating events that occur naturally -- such as winter becoming spring -- to carve our own internal time clock. And this is where things get interesting.
"What typically begins as our brain's ability to register short durations -- from minutes to seconds -- is transformed into an understanding of the flow of time across the lifespan," she said.
What tends to happen, however, is that our internal time clock doesn't always match up as accurately.
When time passes by slowly
According to Irish, the emotional quality of an event strongly modulates our experience of time.
"A number of studies have suggested that negative emotional events, which elicit fear, anger or sadness, produce a time dilation effect, whereby the individual perceives time as passing slowly," Irish told Huffpost Australia.
Researchers have linked this effect to the activation of the amygdala, a structure deep within the brain that responds to arousing events.
The memory may seem to play out more slowly in hindsight than our actual physical experience.
"It has been proposed that rather than altering our perception of time during the fearful event, the activation of the amygdala instead ensures a more detailed memory is encoded, allowing us to vividly remember the experience.
"With greater detail, the memory of the fearful event may seem to play out more slowly in hindsight than our actual physical experience."
Our own level of focus, physical state and mood also comes into play here.
"When we are concentrating on the duration of an event, time seems to pass inexorably more slowly than normal, in line with the phrase 'a watched pot never boils'."
Huh. That explains a lot...
When time speeds up
The same logic can be applied here. Positive events tend to pass by too quickly (like that holiday you took last week...)
Cognitive research has been divided over this one. "This time contraction was initially argued to reflect a positivity bias, whereby we tend to feel that time is passing faster during positive emotional states," Irish said.
According to new research, however, goal-motivation is key.
"When we are motivated to accomplish or pursue something, time appears to speed up as we work in a goal-directed manner to obtain a desired object our outcome," Irish said.
"This can also most likely be a product of our limited attentional resources. When we are multi-tasking and busy with many things at once, we have less attentional resources available to monitor time accurately, leading to the feeling of timing passing by much more swiftly."
Looking forward or back
The influence of emotions on our perception of time can also depend on whether we're looking forwards or backwards.
"When individuals anticipate or imagine pleasure future events, time is perceived as moving more slowly, leading to feelings of impatience," Irish said.
"In contrast, negative emotions such as fear or frustration can lead to anxiety, which in turn produces time contraction."
The mind really is a wondrous thing.
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