This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 766792

The effects of light on health, mood, and performance

Thank you for taking part in this research. This website will give you an overview of the experiment and the tasks we ask you to do. Please take the time to read it in full. You can contact the researcher at any time if you have any question.

Project summary

Without light, we could not see. However, over the past decade or so, it has become increasingly more evident that people also respond to light in non-visual ways. The non-visual effects of light include effects on mood, quality of sleep, general alertness and hormone secretion. In this study, we are investigating the non-visual effects of different types of light (lights of different wavelengths), using new lighting technology that allows advanced control of light spectra. We aim to understand how the non-visual responses to light interact with time of day and type of work performed, and to understand ultimately how these contribute to people's everyday health, emotions and behaviour.

This pilot project, prototype installation and experiment are part of an European Union's Horizon 2020 research project.

What is involved in the study?

Before the experiment starts and right after filling the consent form, we will give you a participant number. This number is your unique identifier in this experiment, meaning that all your data will be kept anonymized. Every time you complete a task you will have to write your participant number, and never your name.

You will have questionnaires and games to do every day and at the time indicated: some of them right after waking up, at morning (between 10:30h - 11h), some at midday (at 16:00h) and some at night before going to sleep. Whenever the time comes, please answer only once the questionnaire indicated (don't submit the same questionnaire twice at the same time). The data will not be sent until you reach the last 'submit' button, so if there is a network connection problem or power drop, you should start the questionnaire again.

Before the experiment

Before the experiment we ask you to take part in an initial assessment, which will include an assessment of your colour vision and several short general health questionnaires (the results of which will be reviewed only by Prof. Hurlbert). This has to be answered only once, at the beginning of the experiment, and never again.

Initial health assessment: link

Other questionnaires

Screen questionnaire (to be answered only once): link

Tasks to complete every day, from the beginning to the end of the 8-weeks experiment

Add a reminder to your calendar

Right after waking up

Sleep diary: link

Morning (10:30-11:00h) – To be done only from Monday to Friday

Morning questionnaire: link

Visual attention game: link

If today is FRIDAY:

Light questionnaire: link

Afternoon (16:00h) – To be done only from Monday to Friday

Afternoon questionnaire: link

Visual attention game: link


If today is FRIDAY:

Light questionnaire: link

Evening-night (before going to sleep)

Evening questionnaire: link