People worldwide are exposed to various light sources daily – whether from natural daylight or artificial lighting. Light exposure significantly influences our well-being and behavior, particularly in relation to sleep, where light plays a crucial role in circadian health and regulating the internal clock. Recent findings suggest that light exposure may also impact the development of myopia (nearsightedness) in children. Light exposure habits, however, vary greatly depending on environmental conditions, individual lifestyles, cultural differences, and climatic factors in different countries.
Globally, research groups are collecting data on "visual light input" to better understand its effects on health. However, a harmonized approach for collecting, storing, processing, and analyzing light exposure data is currently lacking. Prof. Dr. Manuel Spitschan, head of the Assistant Professorship of Chronobiology & Health, aims to establish foundational work for large-scale data synthesis through the "Global Light Exposure Engine" (GLEE) project. This research is supported by an unrestricted gift from Reality Labs Research, a division of Meta.
“We aim to create a central database that allows researchers worldwide to store and analyze data using reproducible methods. To achieve this, we are building an infrastructure for storage and developing new analytical tools for innovative measurement technologies, particularly in the field of wearables,” explains Prof. Dr. Spitschan.
Light exposure data is gathered using specialized devices, such as custom-designed glasses equipped with spectral, luminance, motion, and distance sensors to collect data on a user’s visual environment. Smartwatches worn on the wrist also contribute to such measurements. “By processing standardized metadata and methods, GLEE enhances the reproducibility and accessibility of light exposure data,” Prof Dr. Spitschan adds. “This enables researchers to conduct more comprehensive and precise analyses.” In parallel with the project, Prof. Dr. Spitschan co-leads the „Optical Radiation and Visual Experience" working group in the Research Data Alliance, where metadata standards are developed collaboratively.
An example of how light exposure is measured is demonstrated in the “MeLiDos” project, also led by Prof. Dr. Spitschan and funded by EURAMET e.V. (European Association of National Metrology Institutes). For the first time, harmonized methods are being used to measure data at various locations worldwide. The goal is to analyze environmental and sociocultural influences on light exposure patterns through an international, multicenter study with sites in Germany, the Netherlands, Spain, Sweden, Ghana, and Turkey. “The data collected will help identify lifestyle and context-specific factors that contribute to healthy light exposure and serve as a basis for effective public health measures,” explains Prof. Dr. Spitschan. Within the MeLiDos project, the open-source software LightLogR has already been developed to enable reproducible analysis of light exposure data.
These datasets will be integrated into the GLEE project’s database. In the long term, the initiative aims to improve public health by supporting clinical applications and providing relevant insights for policy decisions concerning light exposure and health. “A vital part of the project will be involving the scientific community. Next year, we plan to introduce a micro-grant program for early-career researchers to participate,” concludes Prof. Dr. Spitschan.
Homepage of the Assistant Professorship of Chronobiology & Health
Homepage of the Translational Sensory and Circadian Neuroscience Unit (MPS/TUM/TUMCREATE)
Homepage of the GLEE Project
Homepage of the Research Data Alliance Working Group
Link to the Study Protocol (Guidolin et al., 2024)
Homepage of the MeLiDos Project
Link to the LightLogR Software
Contact:
Prof. Dr. Manuel Spitschan
Assistant Professorship of Chronobiology & Health
Georg-Brauchle-Ring 60/62
80992 Munich
Tel.: +49 89 289 24544
Email: manuel.spitschan(at)tum.de
Text: Bastian Daneyko
Photos: Private