@article{nokey,

title = {Towards an evidence-based integrative lighting score: a proposed multi-level approach },

author = {O. Stefani and I. Schöllhorn and M. Münch},

doi = {https://doi.org/10.1080/07853890.2024.2381220},

year  = {2024},

date = {2024-07-25},

journal = {Annales of Medicine},

volume = {56},

issue = {1},

pages = {1-16},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Ultradian sleep cycles: Frequency, duration, and associations with individual and environmental factors-A retrospective study },

author = {C. Cajochen and CF. Reichert and M. Münch and V. Gabel and O. Stefani and SL. Chellappa and C. Schmidt 

},

doi = {https://doi.org/10.1016/j.sleh.2023.09.002},

year  = {2024},

date = {2024-02-10},

urldate = {2024-02-10},

journal = {Sleep Health},

number = {1},

issue = {Supplement},

pages = {S52-S62},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{IsabelSchöllhorn2023,

title = {The Impact of Pupil Constriction on the Relationship Between Melanopic EDI and Melatonin Suppression in Young Adult Males},

author = {I. Schöllhorn and O. Stefani and R. J Luca and M. Spitschan, and C. Epple and C. Cajochen

},

doi = {10.1177/07487304241226466},

year  = {2024},

date = {2024-02-01},

urldate = {2024-02-01},

journal = {Journal of Biological Rhythms},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Schöllhorn2023b,

title = {Seasonal Variation in the Responsiveness of the Melanopsin System to Evening Light: Why We Should Report Season When Collecting Data in Human Sleep and Circadian Studies},

author = {I. Schöllhorn and O. Stefani and C. Blume and C. Cajochen},

url = {https://www.mdpi.com/2624-5175/5/4/44},

doi = {https://doi.org/10.3390/clockssleep5040044},

year  = {2023},

date = {2023-11-01},

urldate = {2023-11-01},

journal = {Clocks & Sleep},

abstract = {Abstract

It is well known that variations in light exposure during the day affect light sensitivity in the evening. More daylight reduces sensitivity, and less daylight increases it. On average days, we spend less time outdoors in winter and receive far less light than in summer. Therefore, it could be relevant when collecting research data on the non-image forming (NIF) effects of light on circadian rhythms and sleep. In fact, studies conducted only in winter may result in more pronounced NIF effects than in summer. Here, we systematically collected information on the extent to which studies on the NIF effects of evening light include information on season and/or light history. We found that more studies were conducted in winter than in summer and that reporting when a study was conducted or measuring individual light history is not currently a standard in sleep and circadian research. In addition, we sought to evaluate seasonal variations in a previously published dataset of 72 participants investigating circadian and sleep effects of evening light exposure in a laboratory protocol where daytime light history was not controlled. In this study, we selectively modulated melanopic irradiance at four different light levels (<90 lx). Here, we aimed to retrospectively evaluate seasonal variations in the responsiveness of the melanopsin system by combining all data sets in an exploratory manner. Our analyses suggest that light sensitivity is indeed reduced in summer compared to winter. Thus, to increase the reproducibility of NIF effects on sleep and circadian measures, we recommend an assessment of the light history and encourage standardization of reporting guidelines on the seasonal distribution of measurements.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Danilenko2022,

title = {Wearable Light-and-Motion Dataloggers for Sleep/Wake Research: A Review},

author = {K. Danilenko and O. Stefani and K. Voronin and M. Mezhakova and I. Petrov and M. Borisenkov and A. Markov and D. Gubin },

editor = {Sung Bum Pan},

url = {https://www.mdpi.com/2076-3417/12/22/11794/htm},

doi = {https://doi.org/10.3390/app122211794},

issn = {2076-3417},

year  = {2022},

date = {2022-11-20},

journal = {Applied Sciences},

volume = {12},

number = {22},

abstract = {Long-term recording of a person’s activity (actimetry or actigraphy) using devices typically worn on the wrist is increasingly applied in sleep/wake, chronobiological, and clinical research to estimate parameters of sleep and sleep-wake cycles. With the recognition of the importance of light in influencing these parameters and with the development of technological capabilities, light sensors have been introduced into devices to correlate physiological and environmental changes. Over the past two decades, many such new devices have appeared from different manufacturers. One of the aims of this review is to help researchers and clinicians choose the data logger that best fits their research goals. Seventeen currently available light-and-motion recorders entered the analysis. They were reviewed for appearance, dimensions, weight, mounting, battery, sensors, features, communication interface, and software. We found that all devices differed from each other in several features. In particular, six devices are equipped with a light sensor that can measure blue light. It is noteworthy that blue light most profoundly influences the physiology and behavior of mammals. As the wearables market is growing rapidly, this review helps guide future developments and needs to be updated every few years.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Weng2022,

title = {Impact of Evening Light Exposures with Different Solid Angles on Circadian Melatonin Rhythms, Alertness, and Visual Comfort in an Automotive Setting},

author = {M. Weng and I. Schöllhorn and M. Kazhura and B. Cardini and O. Stefani},

editor = {Robert Lucas},

url = {https://www.mdpi.com/2624-5175/4/4/47},

doi = { https://doi.org/10.3390/clockssleep4040047},

issn = {2624-5175},

year  = {2022},

date = {2022-10-26},

journal = {Clocks & Sleep},

volume = {4},

number = {4},

pages = {607-622},

abstract = {Future automotive interior lighting might have the potential to go beyond decorative purposes by influencing alertness, circadian physiology, and sleep. As the available space in the interior of an automobile for lighting applications is limited, understanding the impact of various luminous surface sizes on non-image-forming effects is fundamental in this field. In a laboratory study using a within-subject design, 18 participants were exposed to two bright light conditions with different solid angles and one dim light condition in a balanced, randomized order during the course of the evening. Our results demonstrate that both light conditions significantly increased subjective alertness and reduced salivary melatonin concentration but not cognitive performance compared to dim light. The solid angle of light exposure at constant corneal illuminance only affected visual comfort. While subjective alertness can be increased and melatonin can be attenuated with rather small luminaires, larger solid angles should be considered if visual comfort is a priority.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Cajochen2022,

title = {Influence of evening light exposure on polysomnographically assessed night-time sleep: A systematic review with meta-analysis },

author = {C. Cajochen and O. Stefani and I. Schöllhorn and D. Lang and S. Chellappa},

doi = {https://doi.org/10.1177/14771535221078765},

year  = {2022},

date = {2022-01-10},

urldate = {2022-01-10},

journal = {Lighting Research & Technology},

volume = {54},

pages = {609-654},

abstract = {Evening exposure to electric light can acutely suppress melatonin levels and adversely affect subsequent sleep. We conducted a systematic review with meta-analysis investigating the influence of evening illuminance levels on polysomnographically (PSG)-assessed sleep. We also explored how melanopsin (expressed in melanopic equivalent daylight illuminance (EDI) affects human sleep features. We included polysomnographic laboratory sleep studies with healthy humans for effects of illuminance and exposure duration, for pre-sleep exposures between 6:00 p.m. to 1:00 a.m. From 440 identified articles, 114 met eligibility criteria for screening, and 21 also reported type of light source/spectral characteristics, with 12 identified as eligible for review. Meta-analysis showed evening light affects sleep latency, sleep efficiency and slow wave sleep, with overall effect sizes (95% confidence interval) of 0.69 (−0.50; 1.88), 0.34 (−0.13; 0.82) and −0.61 (−1.85; 0.62), respectively. Estimated melanopic EDI in the range of 100–1000 lx yielded clear dose–response relationships for sleep latency and sleep efficiency, but not for slow wave sleep. Whilst illuminance and duration indicated no apparent effects for a single evening light exposure on PSG-assessed sleep latency, sleep efficiency and slow wave sleep, we observed evidence for a relationship between light exposure and sleep effects based on melanopic EDI. Hence, melanopic EDI may provide a robust predictor of non-visual responses on human sleep.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gimenez2022,

title = {Predicting melatonin suppression by light in humans: unifying photoreceptor-based equivalent daylight illuminances, spectral composition, timing and duration of light exposure},

author = {M. Gimenez and O. Stefani and C. Cajochen and D. Lang and G. Deuring and L.J.M. Schlangen},

doi = { https://doi.org/10.1111/jpi.12786},

year  = {2022},

date = {2022-01-03},

journal = {Journal of Pineal Research},

abstract = {Light-induced melatonin suppression data from 29 peer-reviewed publications was analysed by means of a machine learning approach to establish which light exposure characteristics (i.e. photopic illuminance, five α-opic equivalent daylight illuminances (EDIs), duration and timing of the light exposure, and the dichotomous variables pharmacological pupil dilation and narrowband light source) are the main determinants of melatonin suppression. Melatonin suppression in the dataset was dominated by four light exposure characteristics: 1. melanopic EDI, 2. light exposure duration, 3. pupil dilation and 4. S-cone-opic EDI. A logistic model was used to evaluate the influence of each of these parameters on the melatonin suppression response. The final logistic model was only based on the first three parameters, since melanopic EDI was the best single (photoreceptor) predictor that was only outperformed by S-cone-opic EDI for (photopic) illuminances below 21 lux. This confirms and extends findings on the importance of the metric melanopic EDI for predicting biological effects of light in integrative (human centric) lighting applications. The model provides initial and general guidance to lighting practitioners on how to combine spectrum, duration and amount of light exposure when controlling non-visual responses to light, especially melatonin suppression. The model is a starting tool for developing hypotheses on photoreceptors’ contributions to light’s non-visual responses and helps identifying areas where more data is needed, like on the S-cone contribution at low illuminances.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zandi2021,

title = {Optimising metameric spectra for integrative lighting to modulate the circadian system without affecting visual appearance},

author = {B. Zandi and O. Stefani and A. Herzog and L. Schlangen and Q. Trinh and T. Khanh },

url = {https://www.nature.com/articles/s41598-021-02136-y},

doi = {https://doi.org/10.1038/s41598-021-02136-y},

year  = {2021},

date = {2021-11-30},

journal = {Scientific Reports},

volume = {11},

number = {23188},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Stefani2021,

title = {Should We Re-think Regulations and Standards for Lighting at Workplaces? A Practice Review on Existing Lighting Recommendations},

author = {O. Stefani and C. Cajochen },

editor = {S. Rahman

},

url = {http://www.chronobiology.ch/wp-content/uploads/2021/09/fpsyt-12-652161.pdf},

doi = {10.3389/fpsyt.2021.652161},

year  = {2021},

date = {2021-05-13},

journal = {Frontiers in psychiatry},

volume = {12},

abstract = {Nowadays lighting projects often include temporal variations of the light, both spectrally

and in terms of intensity to consider non-visual effects of light on people. However, as

of today there are no specific regulations. Compliance with common lighting standards

that address visual aspects of light, often means that only little non-visually effective

light reaches the eye. In this practice review we confront existing regulations and

standards on visual lighting aspects with new recommendations on non-visual aspects

and highlight conflicts among them. We conclude with lighting recommendations that

address both aspects},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Stefani2020,

title = {Changing color and intensity of LED lighting across the day impacts on circadian melatonin rhythms and sleep in healthy men},

author = {O. Stefani and M. Freyburger and S. Veitz and T. Basishvili and M. Meyer and J. Weibel and K. Kobayashi and Y. Shirakawa and C. Cajochen},

url = {http://www.chronobiology.ch/wp-content/uploads/2021/09/Changing-color-and-intensity-of-LED-lighting-across-the-day-impacts-on-circadian-melatonin-rhythms-and-sleep-in-healthy-men.pdf},

doi = {10.1111/jpi.12714},

year  = {2020},

date = {2020-12-30},

journal = {Journal of Pineal Research},

volume = {70},

keywords = {},

pubstate = {published},

tppubtype = {article}

}