Effects of light on attention of fulltime daytime workers – a laboratory study

In addition to its impact on our circadian rhythm, researchers have investigated also alerting effects of light. While effects of light on sleep-wake rhythm and hormone cycles are well proven, evidence for effects on attention is less clear. Circadian effects of light can be best predicted by the activation of ipRGCs within the retina. Hence, we wanted to test the hypothesis whether an increase in activation leads to an improvement of attention during the day. Here we present a laboratory study that focused on alerting effects of light on fulltime daytime workers. We included a workday-like exposure duration and lighting scenes that comply with regulations for office workplaces. It was found that besides attention, participants' mood and perceived well-being were also affected. Contrary to our hypothesis, the results for different correlates of attention were best under lighting with the least activation of ipRGCs

24-Stunden-Lichtexposition unterschiedlicher Berufsgruppen

Im Rahmen eines Forschungsprojekts der Bundesanstalt für Arbeitsschutz und Arbeitsmedizin (BAuA) wurde die Lichtexposition unterschiedlicher Berufsgruppen untersucht. Die Ergebnisse zeigen die Abhängigkeit der Lichtexposition der Beschäftigten in Bezug auf die Arbeitszeiten (Tag- oder Nachtschicht), den Arbeitsort (Arbeit in Innenräumen oder im Freien) und die Jahreszeiten (Winter oder Frühling). Die Lichtexposition der nachtschichtarbeitenden Beschäftigten und der Beschäftigten, die in Innenräumen arbeiten, ist deutlich niedriger als die Lichtexposition der im Freien arbeitenden Beschäftigten. Eine geringe Tageslichtexposition sowie die nächtliche Lichtexposition könnten zu einer Desynchronisation circadianer physiologischer Prozesse im menschlichen Körper und zu gesundheitlichen Beeinträchtigungen führen

Effects of Light on Attention during the Day: Spectral Composition and Exposure Duration

The aim of the study is to investigate effects of light on attention during the day. In particular, changes in spectral composition and prolonged exposure durations are analyzed. The study design was developed to explicitly refer to working days of fulltime daytime workers and therefore increase the transferability to real-life work situations. A combination of subjective scales and psychomotoric tasks is used to address different types of cognitive processes and get a holistic picture of the attentional state. In general, this study contributes to a more precise description of alerting effects of light that may lead to lighting designs that actively support employees at their workplace in the future

ENLIGHT: A consensus checklist for reporting laboratory-based studies on the non-visual effects of light in humansResearch in context

Summary: Background: There is no consensus on reporting light characteristics in studies investigating non-visual responses to light. This project aimed to develop a reporting checklist for laboratory-based investigations on the impact of light on non-visual physiology. Methods: A four-step modified Delphi process (three questionnaire-based feedback rounds and one face-to-face group discussion) involving international experts was conducted to reach consensus on the items to be included in the checklist. Following the consensus process, the resulting checklist was tested in a pilot phase with independent experts. Findings: An initial list of 61 items related to reporting light-based interventions was condensed to a final checklist containing 25 items, based upon consensus among experts (final n = 60). Nine items were deemed necessary to report regardless of research question or context. A description of each item is provided in the accompanying Explanation and Elaboration (E&E) document. The independent pilot testing phase led to minor textual clarifications in the checklist and E&E document. Interpretation: The ENLIGHT Checklist is the first consensus-based checklist for documenting and reporting ocular light-based interventions for human studies. The implementation of the checklist will enhance the impact of light-based research by ensuring comprehensive documentation, enhancing reproducibility, and enabling data aggregation across studies. Funding: Network of European Institutes for Advanced Study (NETIAS) Constructive Advanced Thinking (CAT) programme; Sir Henry Wellcome Postdoctoral Fellowship (Wellcome Trust, 204686/Z/16/Z); Netherlands Organisation for Health Research and Development VENI fellowship (2020–09150161910128); U.S. Department of Defense Grant (W81XWH-16-1-0223); National University of Singapore (NUHSRO/2022/038/Startup/08); and National Research Foundation Singapore (NRF2022-THE004-0002)