Human beings exhibit marked differences in habits, lifestyles and behavioral tendencies. One of these differences, known as chronotype, is the inclination to sleep and wake up early or alternatively to sleep and wake up late.

Changes in society, such as the introduction of portable devices and video streaming services, may have also influenced people’s behavioral patterns, offering them further distractions that could occupy their evenings or late nights. Yet past studies have found that sleeping and waking up late is often linked to a higher risk of being diagnosed with mental health disorders, such as depression and anxiety disorders, as well as poorer physical health.

Understanding the neurobiological underpinnings of humans’ chronotypes, as well as the possible implications of being a so-called “morning person” or “night owl,” could thus be beneficial. Specifically, it could inform the development of lifestyle interventions or medical treatments designed to promote healthy sleeping patterns.

Researchers at the University Health Network (UHN) and the University of Toronto have developed a skin-based test that can detect signature features of progressive supranuclear palsy (PSP), a rare neurodegenerative disease that affects body movements, including walking, balance and swallowing.

The test, which the researchers describe in a recent issue of JAMA Neurology, could allow for more accurate and faster PSP diagnosis than current methods.

“This assay is important for assigning patients to the correct clinical trials, but it will be even more important in the future as researchers develop targeted, precision treatments for PSP,” says Ivan Martinez-Valbuena, a scientific associate at the Rossy Progressive Supranuclear Palsy Centre at the UHN’s Krembil Brain Institute and U of T’s Tanz Centre for Research in Neurodegenerative Diseases.