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The World’s Largest Sleep Study Used Creyos Research to Reach Tens of Thousands of Participants
Cognitive Research

The World’s Largest Sleep Study Used Creyos Research to Reach Tens of Thousands of Participants

Published: 01/05/2018

Written by: Creyos


  • Sleep deprivation impairs cognitive performance as much as alcohol, but surprisingly little is known about exactly how much the brain is affected, and who is most susceptible.
  • Researchers from Western University’s Brain and Mind Institute needed tens of thousands of participants all over the world—so traditional in-person cognition tests would not be feasible.
  • The tests needed to be engaging enough that participants didn’t drop out, and repeatable so they could record cognition over several nights.



  • Creyos Research provided a scientifically-validated measure of the cognitive domains that matter, along with a way of delivering them to participants at an unprecedented scale.
  • An online portal was created to gather information about sleep, cognition, and other details about tens of thousands of people.
  • Despite the massive number of participants, it was simple to store and secure participant data, then download it for analysis when the study was complete.



  • Tens of thousands of participants completed assessments, ensuring that The World’s Largest Sleep Study lived up to its name.
  • The importance and novelty of the study attracted media attention from major outlets, attracting participants and raising the profile of the researchers.
  • Data is currently being analyzed, and the researchers anticipate publishing several groundbreaking papers based on the results.


We All Need Sleep—But How Much?

Lack of sleep is bad for the brain. Past studies have found that after being awake for 18 hours—the equivalent of a late night out—most people are as cognitively impaired as when they are intoxicated by alcohol. Extend these effects to an entire population that is frequently sleep deprived, and it adds up to widespread loss of productivity, workplace accidents, and other tragic results of cognitive impairment.

Research on small groups of people in sleep labs has revealed a lot about how individuals are affected by sleep loss. There are still unanswered questions, however: exactly how much sleep is “enough” to avoid drops in cognition? Who is most affected by sleep loss, and does the effect of sleep on the brain change with age? Which specific aspects of cognition are most impaired? And do results from the lab hold true out there in the real world?


The World’s Largest Sleep Study Used the Latest Technology to Break New Ground in Sleep Research

Researchers from Western University’s Brain and Mind Institute, led by Adrian Owen (the renowned neuroscientist behind Cambridge Brain Sciences), used the power of Creyos Research and its ability to deliver cognitive tests over the Internet to answer these questions.

Over several days, participants answered questions about themselves, tracked their sleep, and completed the Creyos (formerly Cambridge Brain Sciences) 12-test battery to measure measures aspects of inhibition, selective attention, reasoning, verbal short-term memory, spatial working memory, planning, visuospatial working memory, and cognitive flexibility. The study ran for several months, without the need for manual intervention from the researchers or staff, and the data was securely stored for later analysis. The result was an extremely rich data set that would not have been possible without the Creyos Research platform.


Creyos Research Enabled an Ambitious Study to Exceed Expectations

The study’s size and important subject matter attracted international media attention, launching with television and online features on the BBC, then covered by CBC, The Huffington Post, and CNN, raising the profile of the researchers involved and recruiting a sample size that ensured the study lived up to its name. In the end, tens of thousands of participants generously donated their time to complete the study.

The researchers are now analyzing the data. With a wealth of demographic, sleep, and cognition data, they expect that the study will result in several papers, and the novelty and size of the study will ensure they are published in high-profile journals. Early results not only confirm the results of previous lab studies in a naturalistic setting, but reveal some surprises and new research questions as well.

Are you planning a study on cognition? It doesn’t have to be the world’s largest—Creyos Research scales to any size, either in a lab or in participants’ homes. To try it for yourself, visit our website and set up a demo.

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