People with orbitofrontal cortex “respond rapidly to rewards and [punishments] without assessing the consequences sufficiently,” Berlin writes.

So one’s perception of time seems to affect one’s ability to stay calm, to assess a situation, and to make good decisions. As time slows down, these abilities are strengthened. When the orbitofrontal cortex is damaged, Berlin and Morgan’s findings show that this might very well lead to greater stress and a faster perception of time. But neurology is just one piece of the puzzle. Part of the mystery of inaccurate time perception can also be illuminated by psychology.

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In 2009, Aaron Sackett from the University of Chicago conducted an experiment to test whether people’s expectations could affect how they perceived time. He gave 37 American undergraduate students a selection of text and asked them to underline each word that had a double-letter combination (for example: “This is an epigrammatic riddle. ”) Sackett’s research assistant, Rachel Auer, told the participants that the test would last 10 minutes, then made a show of starting her stopwatch and walking out of the room.

Auer conducted two versions of the experiment, each with two variations. In the first version, she varied the amount of time participants were given before she walked back into the room. For one set of participants, time was artificially sped up; they were given only five minutes to take the test before Auer walked back in saying 10 minutes had passed. For the other set of students, time was slowed down; they were actually given 20 minutes, but still told that 10 minutes had passed.

In the second version of the experiment, Auer held the amount of time constant, but varied how much time she told them had passed. Both sets of participants were given 10 minutes to take the test, but one set was told that only five minutes had passed, while the other set was told they’d been given 20 minutes.

After each experiment, the participants were asked to rate how engaging, enjoyable, and challenging they found their task. Both sets of participants for whom time had been “sped up”–that is, the set that were given only five minutes, and the set that were told only five minutes had passed–rated their task as significantly more enjoyable than the other set.

Sackett therefore concluded in his paper and in our conversations that simply being told that time is moving quickly might affect the brain’s perception of time as well. So external cues could also play a role in how quickly or slowly people feel time to be passing.

“If you set the expectation [of a certain amount of time having passed] and then their experience doesn’t fulfill that expectation, it’s quite possible that they would engage in this process of misperceiving time,” Sackett says.

So distorted time perception could be as simple as expecting time to pass in a certain way and then finding that it did not.