4 junio, 2015

Programme: Workshop Digital Light and human health

The Workshop

This scientific event is organized by the Lighting Group of IREC (Catalonia Institute for Energy Research) in the framework of the FP7 Programme Project “HI-LED: Human-centric Intelligent LED engines for the take up of SSL in Europe”.

Lighting conditions affect to cognitive abilities and behaviours. Full control of spectral features of lighting enables the possibility of discriminating and individually exploiting such effects. SSL light-engines with added intelligence offer the possibility of tailoring spectral distributions respectful with our circadian rhythms or capable of inducing desired effects on behaviour, mood and/or physiology.


Thursday 18th June 2015.   3:00 – 7:00 pm
Hotel SB Diagonal Zero
Plaça de Llevant, s/n
08019 Barcelona,Spain

Registration is required for this event on this webpage:


3:00 pm – 3:15 pm, Presentation of “HI-LED project”, Dr. J. Carreras and Dr. M .Perálvarez,
(Catalonia Institute for Energy Research IREC, Spain)

3:15 pm – 3:50 pm, Keynote 1: “Biological effects of light: implications for human health”, Dr. C. Gronfier (Institut National de la Santé et de la recherche médicale INSERM, France)

3:50 pm – 4:25 pm, Keynote 2: “Using Tuneable LED Light Sources to Modulate the Non-Visual Pathway”, Dr. A. Hurlbert and S. Aston (Institute of Neuroscience, Newcastle University, UK)

4:25 pm – 5:00 pm, Keynote 3: “Human Centric Lighting in Application” A. Wojtysiak (OSRAM GmbH, Germany)

5:00 pm – 5:25 pm, Coffe break and networking

5:25 pm – 6:00 pm, Keynote 4: “Light effects on circadian rhythms: Lessons from animals lab”, Dr. T. Cambras (Faculty of Pharmacy, University of Barcelona, Spain)

6:00 pm – 6:35 pm, Keynote 5: “Protecting the melatonin rhythm through circadian healthy light exposure” , Mª Ángeles Bonmatí (Chronobiology Laboratory, University of Murcia, Spain)

6:35 pm – 6:45 pm, Close


Keynote 1: Biological effects of light: implications for human health
Claude Gronfier, Ph.DINSERM U846, Stem Cell and Brain Research Institute, Department of Chronobiology, F-69500 Bron, France.

The visual effects of light are well known. They rely on the activity of classical photoreceptors in the retina, namely rods and cones, and brain areas involved in vision. Rods allow for “black and white” vision under low intensity of light, whereas cones require higher intensities to be activated and allow for color vision. At high intensities and/or at certain spectra, light can be toxic to the eye (phototoxic), lead to retinal degeneration, visual pathologies and blindness.
But the eye is not only involved in vision! The newly discovered (in 2002) melanopsin-containing ganglion cells in the retina are involved in a wide range of non-visual functions, including synchronization of the circadian biological clock and the sleep-wake cycle, alertness, memory, cognition, mood, temperature and heart rate regulation, and the release of neurotransmitters in the brain. These non-classical photoreceptor cells are blue-light sensitive (lambda max ~480 nm), bistable and resist to “bleaching” (desensitization), and were initially thought to require relatively high light intensities to be activated. They appear to be key in the effects of light on health. Indeed, epidemiological and laboratory studies have shown that inappropriate environmental lighting (in intensity, spectrum, or timing) can be involved in clinical disorders. In daily conditions where lighting is not optimal (insufficient intensities or low blue-content), inefficient sleep, low vigilance, altered mood and cognitive functions can be observed. In chronic conditions where the light dark cycle is additionally unstable, such as in shift work, studies show that mood disorders, metabolic and cardiac pathologies, but also cancer are prevalent. Recent studies show that even lighting from LED screens (computers, smartphones, and tablets), in particular before bedtime, can delay the circadian clock, shorten sleep duration, and decrease alertness and cognitive performance in the morning.
It is therefore critical to understand that light is a complex stimulus involved in visual and non-visual functions. Light is absolutely necessary to sustain life and appropriate biological functions in the body, but it can also have important side effects if its quantity (intensity), quality (spectrum), and timing is not right. As we admit that food hygiene is important, it time we think that light hygiene is essential for health.

Keynote 2: Using Tuneable LED Light Sources to Modulate the Non-Visual Pathway
Anya Hurlbert and Stacey Aston. Institute of Neuroscience, Newcastle University, UK

This lecture discusses recent experiments using tuneable LED light sources to generate light stimuli which putatively modulate the non-visual pathway while remaining silent to the visual pathway. We will describe key considerations in generating such stimuli and report preliminary results from a set of behavioural measures.

Keynote 3: Human Centric Lighting in Application
Andreas Wojtysiak, Osram GmbH

Beyond vision, light affects humans physiologically and psychologically with considerable impact on health and wellbeing. Effects known for decades with natural daylight now seem feasible to be achieved by artificial lighting systems. There is general consensus in lighting experts that natural daylight can’t be fully replaced by artificial light, as complex dynamic changes and their impact on wellbeing are not likely to be understood in conceivable time. But despite these limitations, there is also a growing consensus to include recently developed knowledge on non-visual effects of light into interior lighting. The idea is to provide as much as possible all necessary stimuli for the human biology.
In application studies, we have translated the scientific findings into chronobiologically adapted lighting solutions. Together with partners from industry and independent scientific research, we studied the outcome in terms of beneficial effects for performance, health and wellbeing.
For example, circadian effects in an office have been studied with the Institute for Medical Psychology at Ludwig-Maximilian-University in Munich. Social Jetlag in older school pupils and cognitive performance were addressed in cooperation with the Centre for Neuroscience and Learning at the University of Ulm, Germany. Daytime activity and communication as well as sleep/wake rhythms in the elderly have been investigated in long-term studies by the K-Licht consortium in three nursing homes in Vienna, Austria. Reduction of jetlag and improvement of wellbeing for air travel passengers were tested in collaboration with the napcabs GmbH and the Generation Research Program of the LMU Munich. In addition this was studied with partners from aircraft industry (Airbus, Diehl Aerospace) and scientific research (Bergische Universität Wuppertal, Fraunhofer Institute for Building Physics) in realistic night flight simulations. This was followed up in a wellness and spa hotel to check for effects of a chronobiologically adapted 24 hour schedule on physiological markers and psychological self-reports.
Taken together, we see from application studies and basic research that aligning of body’s rhythms with natural ones is a key factor for mood, performance, and health. In the presentation, we will highlight on our experiences in these studies to eliciting non-visual lighting effects in different application fields.

Keynote 4: Light effects on circadian rhythms: Lessons from animals lab.
Trinitat Cambras. Departament de Fisiologia. Facultat de Farmàcia.Universitat de Barcelona

The analysis of the circadian behavioural patterns induced by light in animals lab provides a tool to hypothesize about the functioning and alterations of the circadian system and to speculate about their responses on humans.Chronodisruption induced by light alters activity patterns as well as metabolism. This effect may depend on the age of the animals and on the previous lighting conditions. In this sense the imprinting of perinatal light on the circadian system is a matter of debate.The experimental data should provide reflexions to test the best light patterns for human health.

Keynote 5: Protecting the melatonin rhythm through circadian healthy light exposure
María Ángeles Bonmatí Carrión.Chronobiology Laboratory, University of Murcia, Spain

Currently, in developed countries, nights are excessively illuminated (light at night), whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization of our circadian system or chronodisruption (CD), including perturbations in melatonin rhythm. Epidemiological studies show that CD is associated with an increased incidence of diabetes, obesity, heart disease, cognitive and affective impairment, premature aging and some types of cancer. Knowledge of retinal photoreceptors and the discovery of melanopsin in some ganglion cells demonstrate that light intensity, timing and spectrum must be considered to keep the biological clock properly entrained. Importantly, not all wavelengths of light are equally chronodisrupting. Blue light, which is particularly beneficial during the daytime, seems to be more disruptive at night, and induces the strongest melatonin inhibition. Nocturnal blue light exposure is currently increasing, due to the proliferation of energy-efficient lighting (LEDs) and electronic devices. Thus, the development of lighting systems that preserve the melatonin rhythm could reduce the health risks induced by chronodisruption.