THE LIGHT CAFÉ · SCIENTIFIC BACKGROUND
The Light Café: a field study of morning light.
As the days grow shorter, we get less daylight. Morning light can help us get the day started. At the Light Café in Tübingen, you can experience light and discover our research into the body clock, sleep and attention.
01 / THE RESEARCH QUESTION
How does morning light
affect circadian timing?
How do light intensity and spectral composition shape the human circadian response in everyday settings?
The Light Café is a field study combining controlled morning light exposure with circadian, behavioural and subjective outcome measures. It asks how responses vary across light conditions and between individuals.
The mobile research trailer at Europaplatz, by Tübingen’s main railway station, serves as both an intervention space and a meeting place for researchers and the public. The Light Café opens on 19 November 2026; the study phase will take place from January 2027 onwards.
The long-term aim is to inform biologically grounded, more personalised light interventions. These are research objectives, not established outcomes of this project.
02 / STUDY DESIGN
The study
at a glance.
Sequential cohorts with light conditions
adapted in response to previous observations.
per participant
over two weeks
across 6–8 cohorts
- BASELINE
Baseline
measurementsAssess circadian phase with dim-light melatonin onset (DLMO), alongside actigraphy and cognitive performance measures.
- INTERVENTION
Morning light
sessionsTen one-hour sessions on weekdays, within four daily time windows between 07:00 and 11:00. Light intensity and spectral composition are controlled.
- FOLLOW-UP
Repeat assessments
and analyse the data.Repeat the assessments and collect subjective tiredness and well-being measures. Analyse each cohort to inform subsequent light conditions.
The recruitment target is up to six participants per time window and up to 24 per cohort. The sample range is an operational recruitment estimate, not a reported power calculation or an achieved sample. Exact light settings, eligibility criteria, allocation procedures and adaptation rules are not yet specified here.
03 / OUTCOME DOMAINS
What we
measure.
Circadian, behavioural
and subjective measures.
- Circadian phase DLMO
- Timing of the evening rise in melatonin under dim-light conditions, measured before and after the intervention.
- Sleep and activity ACTIGRAPHY
- Objective assessment of rest–activity patterns using a wearable sensor.
- Cognition PERFORMANCE
- Tasks assessing cognitive performance and attention alongside the physiological measurements.
- Daily experience SELF-REPORT
- Subjective tiredness and well-being following the intervention.
Research and
public engagement
Visit the Light Café to experience light and get to know our research.
The public drop-in takes place on Friday, 20 November, and Monday–Friday, 23–27 November 2026, from 07:00 to 11:00 each day at Europaplatz, Tübingen. Visitors can attend this open programme before the study phase.
Three talks with Manuel Spitschan accompany the programme: 24 November 2026, 18:00–19:00 at Werkstadthaus in Tübingen; 1 December 2026, 13:00–14:00 online via Zoom; and 4 December 2026, 15:30–17:00 at the Hirsch-Begegnungsstätte, Hirschgasse 9, Tübingen. All three talks are in German. Event details, registration and flyers
Our Lunch Bytes talk on 1 December is part of Mental Health Days 2026. Explore the full programme on the University of Tübingen website (in German)
The trailer was previously used for the “Nachtmensch oder Frühaufsteher?” science roadshow, which is no longer active. Its former website remains available as an archive. Archived Roadshow website (in German)
The Light Café project investigates methods for adaptive field interventions and how light conditions relate to circadian, sleep and cognitive outcomes.
Current project flyer (A4 PDF, in German)04 / TEAM & SCIENTIFIC CONTACT
A project of the Translational Sensory and Circadian Neuroscience research group.
At the Max Planck Institute for Biological Cybernetics in Tübingen, we investigate how light influences human physiology and behaviour.
Prof. Dr. Manuel Spitschan leads the project. Chikondano Daza is a research associate on the team.
SCIENTIFIC ENQUIRIES
Scientific
contact
For questions about the study or potential scientific collaboration, contact the scientific lead.
Contact Manuel SpitschanRegister your interest in taking part. Submitting this form does not confirm enrolment.
For visits and participation: info@wasmachtlicht.de · Dates and participation information in German.
Find the Light Café.
Europaplatz · Tübingen
Our mobile research trailer is on Europaplatz, next to Tübingen main railway station.