Are you a night owl or an early riser? – 09/11/2023 – Science

Timing is everything. For both early risers and late sleepers, listening to your internal clock can be the key to success. From the classroom to the courtroom and beyond, people perform best on challenging tasks at a time of day that aligns with their circadian rhythm.

Circadian rhythms are powerful internal timers that guide a person’s physiological and intellectual functioning throughout the day. The peaks in these circadian rhythms vary between individuals.

Some people, known in some countries as “larks” or morning chronotypes, peak early and feel better in the morning. Others, known as “owls” or nocturnal chronotypes, peak late in the day and perform best in the late afternoon or evening.

And some people show neither morning nor evening preferences and are considered neutral chronotypes.

As a researcher looking for ways to improve cognitive function, I explored whether chronotype affects your mental performance. Understanding the types of mental processes that vary — or remain stable — throughout a day can help people schedule their tasks in a way that optimizes performance.

Why your chronotype matters

Chronotype can be measured with a simple questionnaire that assesses things like your perceived alertness, preferred wake and sleep times, and performance throughout the day. Even without a questionnaire, most people know whether it’s a lark or an owl or somewhere in between.

Do you wake up early without an alarm clock and feel excited? Are you mentally exhausted and ready to wear your pajamas at nine? If so, you’re probably the morning type. Do you sleep late and wake up feeling sluggish and confused? Do you have more energy late at night? If so, you’re probably the night owl type.

People perform better at many challenging mental tasks — from paying attention and learning to solving problems and making complex decisions — when these actions are synchronized with their personal circadian peaks.

This is known as the synchronization effect. Whether you’re an air traffic controller scanning the radar, a finance chief reviewing an earnings report, or a high school student learning chemistry, timing can affect your performance.

Much of the evidence for synchrony effects comes from laboratory studies that test larks and owls early in the morning and late in the day. People with strong chronotypes are more vigilant and better able to maintain attention during peak times compared to off-peak times. Their memories are sharper, with better recall of lists and more success in remembering “to do” tasks such as taking medication.

People are also less likely to mind wander and less distracted at the ideal time. For example, one study I conducted gave participants three keywords that weren’t very directly related (like “ship,” “external,” and “crawl”).

They were tasked with finding another word that linked the three (like “space”). When my team and I presented deceptive words along with the keywords (such as “ocean” for ship, “inside” for exterior, and “baby” for crawl), those who were tested at synchronous times were better at ignoring the deceptive words and find the target solution.

Synchrony also affects higher-level cognitive functions such as persuasion, reasoning, and decision-making. Consumer studies have found that people are more discerning, skeptical and analytical during peak times. They invest more time and effort in assigned tasks and are more likely to look for important information. Consequently, people make better investment decisions, are less prone to bias and more likely to detect fraud.

Outside of peak times, people take longer to solve problems and tend to be less careful and more dependent on mental shortcuts, which leaves them more vulnerable to flashy marketing schemes. Even ethical behavior can be compromised at non-optimal times, as people are more likely to cheat during off-peak hours.

In the classroom and in the clinic

The basic mental abilities that are affected by synchrony — including attention, memory, and analytical thinking — are all skills that contribute to academic success. This connection is especially meaningful for teenagers, who tend to be night owls but typically start studying at an early time.

The time of day may also be taken into consideration when performing assessments for cognitive disorders such as attention deficit disorder or Alzheimer’s disease.

Scheduling time may be particularly meaningful for older adults, who tend to be playful and often show greater synchrony effects than young adults.

Performance is better at peak times on several important neuropsychological measures used to assess these conditions. Not considering synchrony can affect the accuracy of diagnoses and, consequently, affect the eligibility of clinical trials and data on treatment efficacy.

Of course, synchrony does not affect the performance of all tasks or all people. Simple, easy tasks—like recognizing familiar faces or places, dialing a close friend’s phone number, or preparing a favorite recipe—are unlikely to change throughout the day. Furthermore, young adults who are neither larks nor owls show less variability in performance throughout the day.

For those who are early risers or night owls, tackling more difficult mental tasks at times that align with your personal circadian peaks can improve your results. When small improvements in performance provide a critical advantage, timing can be a secret to success.

*Cindi May is a professor of psychology at the College of Charleston, in the state of South Carolina, in the United States

**This article was published on The Conversation and reproduced here under a Creative Commons license. Click here to read the original version in English.