Study on the effects of near-infrared is up and running

In November, we started with recruiting new participants for the study on the effects of near-infrared light. Purpose was to include 20 more subjects in winter. The task was to include them all within 3 weeks to be ready before Christmas. And yes! We are happy to announce that we managed to find 20 enthusiastic…

Events on Daylight saving time issue 2021

Marijke Gordijn is invited for several public events (in Dutch) on the topic of Daylight saving time. The first one will be an interview organised by Studium Generale Utrecht in collaboration with Tivoli/Vredenburg. On October 28th, at 8:15 pm on the stage of Tivoli-Vredenburg in Utrecht, Marijke will talk about the role of the biological…

We are hiring!

Do you like translating scientific knowledge into practical solutions for society? Do you have knowledge in the fields of chronobiology and sleep? Do you want to gain experience in a science-driven young and unique company? Then we are looking for you as our new junior science advisor. Who are we looking for? A young scientist…

Article in LED Magazine

“Artificial light in most offices and homes undermines performance, well-being and health; it’s time for change and that starts with a new awareness,” says Marijke Gordijn in an article in the LED Magazine of June 2021. Marijke Gordijn has been arguing for the right light at the right time for years. Read the whole article…

Longer and later sleep due to lock down

On January 8th, Marijke Gordijn from Chrono@Work and Roelof Hut from the University of Groningen were interviewed by EditieNL about the effects of the COVID-19 related restrictions on sleep. Colleagues recently published that on average people sleep longer and later during the lockdown. However, shortage of sleep and sleeping problems have serious health effects. EditieNL…

Interview NPO Radio 1 on December 26th

In the early morning of December 26th, Marijke Gordijn from Chrono@Work gave an interview on NPO Radio 1 about the role of light for well being and health. This item is especially interesting in the dark winter days around Christmas in our region. The focus of the interview was on the new study we do…

Tips to improve the regularity of daily routines, even when nothing about your life feels regular!

The COVID-19 pandemic poses a serious health threat to the world population. In response, governments are implementing a variety of new policies including self-quarantine, self-isolation and social distancing. While medically necessary to limit spread, these new social policies can disrupt many of the stabilizing factors in our lives which support mental health. In close collaboration,…

Working from home? Take care you see enough daylight!

The policies to limit spreading of COVID-19 is ‘stay home’ and ‘work from home’. The consequence is that most people see very little daylight. While it is very important to stay home as much as possible and keep ‘social distance’ all the time, in the Netherlands it is not forbidden to go outside. The Dutch…

Campaign against Drowsy Driving

On 3 February 2020, the Flemish Traffic Sciences Foundation in Belgium (Vlaamse Stichting Verkeerskunde or VSV) is launching a campaign to raise awareness of the dangers of ‘drowsy driving’. Sleepiness is one of the main causes of fatal traffic accidents. During the campaign, which runs until March 1, 2020, road users can do an online…

Upcoming lectures on sleep-wake rhythms disturbances and melatonin

Chrono@Work will be present at several symposia, classes and congresses in the upcoming period. Please have a look and subscribe if you are interested in the topic. 16th April 20:00h in Leeuwarden: Studium Generale Het Einde van de Zomertijd en Dan? 18th April whole day in Zeist: Medilex symposium on ‘Slaapproblemen en -stoornissen bij mensen met…

TV program FOCUS on health risks of night work

On November 7th, NTR presented a documentary FOCUS on the health risks of working at night and discusses possible solutions. In accordance with the reports of the Dutch Health Council 2015 and 2017, the most important point is to avoid working at night as much as possible. Roelof Hut from the University of Groningen and…

Plea for Central European Time in the Netherlands

Last weekend Daylight saving time 2018 ended and Europe went back to Central European Time. In a short movie commissioned by the University of Groningen, Marijke Gordijn explained once more why for us, in the Netherlands, the current time we have in winter is the most optimal choice. In fact, The Netherlands should even be…

16 tips to wake up easier in The Guardian

Linda Geddes, journalist in the UK, published an article in the Guardian titled “No more snooze button: a complete guide to waking up feeling fantastic“. “Now the clocks have gone back and the days are getting shorter, it can be hard to get out of bed. But, from dawn simulators to a regular wakeup time,…

Scientific arguments to stop with daylight saving time

Chrono@Work is proactive in spreading scientific arguments for a thoughtfull decision on stopping summer/wintertime. Now that the EU recommends to end changing our clocks twice a year, each country has to decide what to do. The recommendation from the EU is based on years of discussions with and within the parliament and triggered by the outcome…

Winter time !! Not summer time !!

An overwhelming majority of the European population voted against the Daylight Saving Time (DST) clock shifts. Of the 4.6 million respondents to the online survey of the European Commission, no less than 80 percent indicated they wanted to get rid of the shift back and forth in time twice a year. It is now up…

Human solutions for control rooms in Muscat

Invited by Honeywell and Medilux, Chrono@Work gave a lecture in Muscat (Oman) on ‘human solutions for control rooms’. In between very technical lectures and for a very special, interested audience, we talked about putting the human in the center of attention. What can we do to optimize the 24h environment for people working 24/7 in…

In memory | Professor emeritus Serge Daan (1940-2018)

With deep sadness we received the news that Professor emeritus Serge Daan passed away on Friday, February 9th, 2018. Serge Daan is the founder of Chronobiology at the University of Groningen and made human chronobiology possible by building time isolation units back in the nineties at the Biology department. He was a great teacher and…

Health risks of night shift work

As a member of the Committee Nightwork, Marijke Gordijn contributed to a new publication of the Health Council of the Netherlands: Health Risks of night shift work. In the Netherlands about 1.3 million people sometimes or regularly work at night. Night shift work disrupts the day-night rhythm of the body, which may lead to adverse…

“Dokters van Morgen’ on the beneficial effects of light for sleep

In the Dutch Television program ‘Dokters van Morgen‘ on October 17th, Antoinette Herzenberg pays attention to the importance of a healthy sleep. As part of the program, five volunteers went camping during one weekend. Chrono@Work supported the program with scientific input and the analysis of light exposure, rest-activity rhythms and melatonin patterns. Following up on…

Linking light exposure and subsequent sleep: a field polysomnography study in humans

Marijke Gordijn is a co-author of a study featured at Sleep. Study objectives To determine the effect of light exposure on subsequent sleep characteristics under ambulatory field conditions. Methods Twenty healthy participants were fitted with ambulatory PSG and wrist-actigraphs to assess light exposure, rest-activity, sleep quality, timing and architecture. Laboratory salivary dim-light melatonin onset (DLMO)…

Charge your Brainzzz is live!

After a year of hard work we are there! The teaching materials for the package Charge Your Brainzzz are ready. Charge your Brains teaches highschool students about sleep. On 27 September, Chrono@Work and the Dutch Brain Foundation will launch this special educational package. Charge Your Brainzzz is a modern package with activating learning tools including…

Brain Foundation public day 2017: Brains and stimuli

On Thursday October 12th, the 25th Public Day of the Brain Foundation will take place in De Doelen in Rotterdam, with the theme Brain and stimuli. Language is Dutch. During multiple lectures, prominent brain researchers report on their brain and stimuli research. During the breaks, visitors can take a look at the HersenPlaza (formerly Information…

Launching teaching material Charge Your Brainzzz

Wednesday September 27th, Chrono@Work and the Brain Foundation will launch the new teaching material Charge Your Brainzzz in the Corpus Congress Centre in Leiden. Charge Your Brainzzz consists of a package of three lessons about sleep regulation and sleep disorders, with activating learning tools, animations (to be used during class) and a serious game developed…

Is there a relationship between vegetarianism and Seasonal Affective Disorder? A pilot study.

Marijke Gordijn is co-author of a study investigating the relationship between vegetarianism and winter depression, together with researchers from Finland and the university medical center in Groningen. A Background and Aim: Seasonal patterns of food intake are found in healthy individuals and particularly in patients with seasonal affective disorder (SAD). One nutritional choice is a…

Premenstrual mood and empathy after a single light therapy session

To examine whether acute changes in cognitive empathy might mediate the impact of light therapy on mood, we assessed the effects of a single light-therapy session on mood and cognitive empathy in 48 premenstrual women, including 17 who met Premenstrual Symptoms Screening Tool criteria for moderate-to-severe premenstrual syndrome / premenstrual dysphoric disorder (PMS/PMDD). Using a…

Video recordings for e-learning course

Today we started with recording the first video’s for the e-learning course Animal & Human experimentation. Chrono@Work develops this course together with the University of Groningen. In the next academic year, it will be possible to complete this mastercourse that is obligatory for masterstudents working with animals during their research project completely on demand. With…

SAVE THE DATE SLAAP 2017

In continuation of SLAAP2016, the second Dutch Sleep Congress will be organized again this year under the umbrella of the Dutch Society for Sleep-Wake research (NSWO) and the Sleep Medicine Association Netherlands (SVNL) in the Heerlickheijd in Ermelo. SLAAP 2017 is a unique collaboration between the various disciplines who work in the field of Sleep, such…

Sleep disturbances in Phenylketonuria: an explorative study in men and mice.

Marijke Gordijn is coauthor of a study investigating sleep disturbances in PKU. Sleep problems have not been directly reported in phenylketonuria (PKU). In PKU, the metabolic pathway of phenylalanine is disrupted, which, among others, causes deficits in the neurotransmitters and sleep modulators dopamine, norepinephrine, and serotonin. Understanding sleep problems in PKU patients may help explain…

Sleep as part of a healthy lifestyle

What is sleep? Sleep as part of our daily life, This chapter describes the basic principles of sleep and wake regulation, the effects of sleep deprivation due to a mismatch between sleep and the biological clock, and what you can do about it. Every evening, a large behavioral change occurs in almost all people. In…

Chrono@Work moved to a new office!

Chrono@Work has moved to a new office. As from March 1st we are housed in the beautiful old milkfactory De Ommelanden, still very close to our colleagues of the University Groningen. Our new address is Friesestraatweg 213, 9743 AD Groningen. Telephone and email have not changed.

Educational paper published on Chronotherapeutic interventions

Chronotherapeutic interventions Marijke Gordijn of Chrono@Work co-authored a Dutch paper on Chronotherapeutic interventions in Psychiatry. She wrote this paper together with 3 colleagues with whom she also started Chronotherapy Network Netherlands (www.cnn.nl). The paper was published in the continuing education journal Psyfar. Since 2006, Psyfar focusses on educating and testing psychiatrists, hospital pharmacists, geriatrics specialists,…

Review paper on Seasonal affective disorder, winter type.

Seasonal affective disorder, winter type: current insights and treatment options Marijke Gordijn from Chrono@Work co-authored a review paper on Seasonal Affective disorders. Seasonal affective disorder (SAD), winter type, is a seasonal pattern of recurrent major depressive episodes most commonly occurring in autumn or winter and remitting in spring/summer. The syndrome has been well-known for more…

Daylight saving time ends

According to the European directives, Daylight Saving time ends in the last weekend of October. Most European countries follow this directive, which means that this year on October 30 the clock will be shifted back one hour (change from 3 am to 2 am). For us this means an extra hour on the night of…

Radio Noord interview in response to a news report about the fact that 1 out of 6 dutch workers are sleep deprived

On September 12 several media reported that according to a TNS Nipo survey among 3,400 Dutch, that one out of six workers has sleeping problems. In a radio interview with Radio North on September 12 at 13: 40h Marijke Gordijn CEO of Chrono@Work explained what the risks are of sleep deprivation (http://radio.rtvnoord.nl/ipad/index.asp?actie=radiogemist). We should distinguish…

Are blue light filters nonsense?

In their issue No. 19 of 23 August – 6 september, Computer Idee, a magazine about computers and electronics for consumers, pays detailed attention to the pros and cons of blue light filters for computers, tablets and smartphones. The conclusion is that we are exposed to more blue light through the use of electronic screens…

Radio interview in Morad & Shay program

On July 19th  at 17: 15h Marijke Gordijn CEO of Chrono@Work was interviewed by Morad & Shay for the local youth radio station Funx. Following up on a British study from 2015 that discussed the optimal bed-times, times of getting up and working times for young and elderly people. Professor Kelley and colleagues published an…

Presentation: Introduction to Chronotherapy

Marijke Gordijn CEO of Chrono@Work will give a lecture on Wednesday, July 13th at the satellite symposium entitled ARE MOOD DISORDERS CHRONOBIOLOGICAL DISORDERS? This satellite symposium is organized by the Society for Light Treatment and Biological Rhythms on the first day of the 18th Annual Conference of The International Society for Bipolar Disorders (ISBD16) held…

NRC checks…are the Dutch indeed the champions of sleep?

NRC next fact check, examines whether the NRC report in the Algemeen Dagblad of 9 May over Duch being campions at sleeping long is correct. The conclusion was drawn on the basis of an article in Science Advances which made use of data from the worldwide used sleepapp. NRC Next consulted among others, Chrono@Work on this…

Save the date! Sleep 2016

Under the umbrella of the Dutch Association of Sleep-Wake Research (NSWO) and the Sleep Medicine Association Netherlands (SVNL) the first Dutch Sleep Congress, SLEEP 2016.will be organized on the 3-4 November, 2016 in the Heerlickheijd, Ermelo. The conference is a unique interdisciplinary collaboration between different departments working in the field of Sleep, e.g. pulmonologists, neurologists,…

‘We better repeal daylight saving time’

During the night of Saturday to Sunday daylight saving time will start: the clock will move forward one hour. The discussion to get rid of daylight saving time has been going on for many years. NU.nl asked the experts about their opinion. “I think we can better repeal daylight saving time”, states researcher of human…

‘Get rid of your blues’

Trouble getting out of bed, a constant yearning for chocolate, craving Netflix more than sex… The shortest day might be over, but especially in January and February we massively encounter the winter blues. The University of Groningen figured that in roughly 500.000 Dutch people the winter blues takes on such a violent form that they…

‘The role of sleep and time of day on athletic performance’

December 11th 2015 the sympium Licht -Donker -Slaap (Light- Dark- Sleep) took place at the Beurs van Berlage in Amsterdam. Marijke Gordijn was there to give a lecture regarding ‘when every second counts, the role of sleep and time of day on athletic performance”. Why is sleep an important part of your training-schedule? Does it…

Shift work and health risks: possibilities for prevention

Roughly 16% of the Dutch labor force works during the nightly hours on a regular basis. Signals arise from scientific literature that this might not always be healthy. Research does not yet have a decisive answer to which preventive measures protect employees best. A forward rotating schedule or a short bout of sleep during night…

‘Nonsense that summer and wintertime still exist’

ASSEN – Daylight saving time and standard time, almost everyone is affected by it. Some more than others. Some people need four weeks to get back to their ordinary rhythms. Along with the University of Groningen, Marijke Gordijn investigates sleep disorders: “Especially the switch to daylight saving time is tough for people who are sensitive…

‘Is it not better to abolish daylight saving time?’

Marijke Gordijn is researcher at the University of Groningen and entrepreneur. Using her company Chrono@Work she puts knowledge from the field of chronobiology on the market. She tells why daylight saving time should be abolished. Chronobiology got its name in the ‘60s, In Germany research was performed inside a bunker, an area secluded from information…

Sleep and need for recovery in shift workers: do chronotype and age matter?

This study examined associations of chronotype and age with shift-specific assessments of main sleep duration, sleep quality and need for recovery in a cross-sectional study among N ¼ 261 industrial shift workers (96.6% male). Logistic regression analyses were used, adjusted for gender, lifestyle, health, nap behaviour, season of assessment and shift schedule. Shift workers with latest versus earliest…

Human cellular differences in cAMP – CREB signaling correlate with light-dependent melatonin suppression and bipolar disorder

Various lines of evidence suggest a mechanistic role for altered cAMP-CREB (cAMP response element – binding protein) signaling in depressive and affective disorders. However, the establishment and validation of human inter-individual differences in this and other major signaling pathways has proven difficult. Here, we describe a novel lentiviral methodology to investigate signaling variation over long periods of…

The duration of light treatment and therapy outcome in seasonal affective disorder

Background: Seasonal affective disorder (SAD) is characterized by recurrent episodes of major depression with a seasonal pattern, treated with light therapy (LT). Duration of light therapy differs. This study investigates retrospectively whether a single week of LT is as effective as two weeks, whether males and females respond differently, and whether there is an effect of expectations as…

Effects of a chronic reduction of short-wavelength light input on melatonin and sleep patterns in humans: Evidence for adaptation

Light is an important environmental stimulus for the entrainment of the circadian clock and for increasing alertness. The intrinsically photosensitive ganglion cells in the retina play an important role in transferring this light information to the circadian system and they are elicited in particular by short-wavelength light. Exposure to short wavelengths is reduced, for instance, in elderly…