Ethical conduct depends on your body clock, study says

PUBLISHED : Thursday, 24 July, 2014, 1:22am
UPDATED : Thursday, 24 July, 2014, 1:22am

New research suggests that our ability to act honestly in a given situation depends, in part, on the time of day.

A study forthcoming in the journal Psychological Science finds that early risers, or "larks", are more likely to act dishonestly in the late evening hours. Night owls, on the other hand, exhibit a tendency toward ethical lapses early in the morning.

Most of us are hard-wired to go to sleep and wake up at certain times of day. Some of us go to bed early to wake up early, while others prefer to stay up late and wake up late. Many of us fall somewhere in between.

Researchers refer to this preference for sleep times as our "chronotype". Chronotype is "largely determined genetically," explained Sunita Sah, one of the authors of the Psychological Science study. "But it can change over time. Teenagers and students might find their chronotype shifts as they get older."

But it's quite difficult to deliberately reset your body's sleep clock in a short period of time, as any new parent knows.

Sah and her colleagues found that this internal clock also affects our ability to behave ethically at different times of day. When we're tired, we tend to fudge things and cut corners.

Sah measured this by finding out the chronotypes of 140 people via a self-assessment questionnaire, and then asking them to complete a task in which they rolled dice to win raffle tickets - higher rolls, more tickets won.

Participants were randomly assigned to either early-morning or late-evening sessions. Crucially, the participants self-reported their dice rolls.

You'd expect the dice rolls to average out to about 3.5. So the extent to which a group's average exceeds this number is a measure of their collective cheating.

"Morning people tended to report higher die-roll numbers in the evening than the morning, but evening people tended to report higher numbers in the morning than the evening," Sah and her co-authors wrote.