Bedtime, your 'chronotype' and getting things done: Study looks at how sleep and intelligence are linked

A woman sleeps in this undated stock image. (Pexels)

A new study has found that verbal intelligence may be more prominent in early-birds than night-owls, depending on sleeping patterns and natural inclinations.

The study comes as people prepare to roll their clocks back an hour to standard time, and it challenges modern research that suggests that those who stay up late have stronger cognitive abilities in problem solving, abstract reasoning and working memory.

Through assessing the impact of a person’s daily rhythm and activity levels, Dr. Stuart Fogel, a cognitive neuroscientist and professor at the University of Ottawa’s School of Psychology, has potentially unearthed new merit to the old saying “the early bird gets the worm.”

“Once you account for key factors including bedtime and age,” he said in a press release, “we found that morning types tend to have superior verbal ability. This outcome was surprising to us and signals this is much more complicated than anyone thought before.”

But these results hinge on one important factor.

Fogel, the director of the University of Ottawa’s Sleep Research Laboratory, worked with a team of researchers to identify an individual’s “chronotype” – which is their evening or morning tendencies – through assessing daily preferences and biological rhythms. According to Fogel, a person’s chronotype is linked to when they are most willing to engage in demanding tasks, and correlates with optimum performance.

Research indicates that young individuals are typically categorized as “evening types” while older individuals are more likely “morning types.”

Fogel warns that catering schedules, which are incompatible with individuals’ chronotypes, may limit cognitive potential.

“A lot of school times are not determined by our chronotypes but by parents and work-schedules, so school-aged kids pay the price of that because they are evening types forced to work on a morning type schedule,” Fogel said.

“For example, math and science classes are normally scheduled early in the day because whatever morning tendencies they have will serve them well. But the AM is not when they are at their best due to their evening type tendencies. Ultimately, they are disadvantaged because the type of schedule imposed on them is basically fighting against their biological clock every day.”

Through rigorously screening volunteers representing a wide age range, the study measured activity levels while determining sleep patterns and numerous confounding factors. Fogel believes that establishing a person’s rhythm, which fuels overarching intelligence, is the bridge between bedtime and cognitive functionality.

“Our brain really craves regularity and for us to be optimal in our own rhythms is to stick to that schedule and not be constantly trying to catch up,” he said.