Marijke C M Gordijn

University of Groningen | RUG · Centre for Behaviour and Neurosciences (CBN)

Description of a psychiatric phenotype in sighted non-24-hour-sleepwake disorder and effects of treatment.

Background Light therapy (LT) for Seasonal Affective Disorders (SAD) has been a well-known and effective treatment for 40 years. The psychiatric university clinic of Groningen, the Netherlands was an early adopter and started research and treatment of SAD in 1987. Research projects on mechanisms, the role of the circadian system, treatment optimiza...

Modern urban human activities are largely restricted to the indoors, deprived of direct sunlight containing visible and near-infrared (NIR) wavelengths at high irradiance levels. Therapeutic exposure to doses of red and NIR, known as photobiomodulation (PBM), has been effective for a broad range of conditions. In a double-blind, randomized, placebo...

Under real-life conditions, increased light exposure during wakefulness seems associated with improved sleep quality, quantified as reduced time awake during bed time, increased time spent in non-rapid eye movement (NREM) sleep, or increased power of the electroencephalogram delta band (0.5-4 Hz). The causality of these important relationships and...

Aims/hypothesis In our modern society, artificial light is available around the clock and most people expose themselves to electrical light and light-emissive screens during the dark period of the natural light/dark cycle. Such suboptimal lighting conditions have been associated with adverse metabolic effects, and redesigning indoor lighting condit...

Introduction Under real life conditions, increased light exposure during wakefulness seems associated with improved sleep quality, quantified as reduced time awake during bed time, increased time spent in non-REM (NREM) sleep or increased power in the EEG delta band (0.5–4 Hz). The causality of these important relationships and their dependency on...

Circadiane slaap-waakritmestoornissen zijn slaap-waakverstoringen met een afwijkend 24-uurspatroon in de slaap-waakafwisseling. In de psychiatrische praktijk komt de vertraagd slaap-waakritmestoornis (DSPD) veruit het vaakst voor. De prevalentieschatting van DSPD in de algemene bevolking varieert van 0,1 tot 3 %, oplopend bij jongeren tot 16 %. Kla...

Abstract The circadian system affects physiological, psychological, and molecular mechanisms in the body, resulting in varying physical performance over the day. The timing and relative size of these effects are important for optimizing sport performance. In this study, Olympic swim times (from 2004 to 2016) were used to determine time-of-day and c...

Despite an elevated recovery need, research indicates that athletes often exhibit relatively poor sleep. Timing and consolidation of sleep is driven by the circadian system, which requires periodic light-dark exposure for stable entrainment to the 24-hour day, but is often disturbed due to underexposure to light in the morning (e.g., low-level indo...

Mental disorders like major depressive disorder can be modeled as complex dynamical systems. In this study we investigate the dynamic behavior of individuals to see whether or not we can expect a transition to another mood state. We introduce a mean field model to a binomial process, where we reduce a dynamic multidimensional system (stochastic cel...

Light significantly improves alertness during the night (Cajochen, 2007; Ruger et al., 2005), but results are less conclusive at daytime (Lok, Smolders, et al., 2018). Melatonin and core body temperature levels at those times of day may contribute to differences in alerting effects of light. In this experiment, the combined effect of daytime exogen...

Purpose The circadian clock is entrained to light by the intrinsically photosensitive retinal ganglion cells. Loss of these cells in glaucoma, an eye disease with loss of retinal ganglion cells as its key feature, might thus result in a change in chronotype. We aimed to compare the chronotype between glaucoma patients and healthy subjects. Methods...

Data underlying this study. (XLS)

Supplementary_information_White_light_during_daytime_does_not_improve_alertness_in_well-rested_individuals – Supplemental material for White Light During Daytime Does Not Improve Alertness in Well-rested Individuals

Mental disorders like major depressive disorder can be seen as complex dynamical systems. We build on previous work using networks and dynamical systems theory in psychopathology, to investigate the dynamic behaviour of individuals to see whether or not we can expect a transition to another mood state. Here, we introduce a mean field approximation...

Abstract The mammalian circadian system encodes both absolute levels of light intensity and color to phase-lock (entrain) its rhythm to the 24-h solar cycle. The evolutionary benefits of circadian color-coding over intensity-coding per se are yet far from understood. A detailed characterization of sunlight is crucial in understanding how and why ci...

Broad-spectrum light applied during the night has been shown to affect alertness in a dose-dependent manner. The goal of this experiment was to investigate whether a similar relationship could be established for light exposure during daytime. Fifty healthy participants were subjected to a paradigm (0730-1730 h) in which they were intermittently exp...

Objectives: This study examined daily scores of fatigue and circadian rhythm markers over two-week offshore day shift periods. Methods: A prospective cohort study among N = 60 offshore day-shift workers working two-week offshore shifts was conducted. Offshore day shifts lasted from 07:00 - 19:00 h. Fatigue was measured objectively with pre- and...

Mental disorders like major depressive disorder can be seen as complex dynamical systems. We build on previous work using networks and dynamical systems theory in psychopathology, to investigate the dynamic behaviour of individuals to see whether or not they are at risk for a transition to another mood state. Here, we introduce a mean field approxi...

In humans and most other species, changes in the intensity and duration of light provide a critical set of signals for the synchronisation of the circadian system to the astronomical day. The timing of activity within the 24 h day defines an individual’s chronotype, i.e. morning, intermediate or evening type. The aim of this study was to investigat...

To better understand sleep quality and sleepiness problems offshore, we examined courses of sleep quality and sleepiness in full 2-weeks on/2-weeks off offshore day shift rotations by comparing pre-offshore (1 week), offshore (2 weeks) and post-offshore (1 week) work periods. A longitudinal observational study was conducted among N=42 offshore work...

Chronotype questionnaires provide a simple and time-effective approach to assessing individual differences in circadian variations. Chronotype questionnaires traditionally focused on one dimension of chronotype, namely its orientation along a continuum of morningness and eveningness. The Caen Chronotype Questionnaire (CCQ) was developed to assess a...

Significance Human retinas contain five light-responsive cell types: rods; short (S)-, mid (M)-, and long (L)-wavelength–sensitive cones; and melanopsin-expressing ganglion cells. Intrinsically light-sensitive retinal ganglion cells (RGCs) also relay rod and cone information to brain areas involved in nonvisual responses, such as pupil constriction...

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...

Inadequate sleep impairs cognitive function and has been associated with worse academic achievement in higher education students; however, studies that control for relevant background factors and include knowledge on sleep hygiene are scarce. This study examined the association of chronic sleep reduction (i.e. symptoms of chronic sleep reduction su...

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 vegetarian diet. Methods: In a Finnish population study, FINRISK 2012, information about diet and SAD was collected. In a Dutch outpatient clinic, SAD patients were...

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 dysp...

Light is the most potent time cue that synchronizes (entrains) the circadian pacemaker to the 24-h solar cycle. This entrainment process is an interplay between an individual's daily light perception and intrinsic pacemaker period under free-running conditions. Establishing individual estimates of circadian phase and period can be time-consuming. W...

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 the pathophysiology of brain d...

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 than three decades, with light treatment being the treatment of first choice. In this paper, an overview is presented of th...

Psychological disorders like major depressive disorder can be seen as complex dynamical systems. By looking at symptom activation patterns, we can investigate the dynamic behaviour of individuals to see whether or not they are at risk for sudden changes (phase transitions). Here, we show how a mean field approximation is used to reduce a dynamic mu...

Many people in our modern civilized society sleep later on free days compared to work days. This discrepancy in sleep timing will lead to so-called ‘social jetlag’ on work days with negative consequences for performance and health. Light therapy in the morning is often proposed as the most effective method to advance the circadian rhythm and sleep...

Background: Seasonal affective disorder (SAD) is characterized by recurrent episodes of major depression in a seasonal pattern. The therapy of choice is light therapy (LT). It is suggested that LT should be administered relative to the chronotype of the patient, with the optimal timing earlier for morning than for evening types. This study aims to...

Light of short wavelengths has been shown to play a key role in non-image forming responses. Due to aging, the ocular lens becomes more yellow reducing the transmission of short wavelengths in the elderly. In the present study, we make use of cataract surgery to investigate the effects of a relative increase of short wavelength transmission on mela...

- Now that the 24-hour economy is putting an ever-increasing mark on social life, the effects of the disruption of natural biological rhythms are becoming clearer.- In addition to its effects on sleep, this article discusses its long-term health effects.- Potential measures to reduce and counteract the adverse effects of working night shifts on gen...

Unlabelled: 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 = 261 industrial shift workers (96.6% male). Logistic regression analyses were used, adjusted for gender, lifestyle, health, nap behaviour, season of asses...

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 wh...

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 me...

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 wav...

Human cortisol levels follow a clear circadian rhythm. We investigated the contribution of alternation of sleep and wakefulness and the circadian clock, using forced desynchrony. Cortisol levels were best described by a multiplication of a circadian and a wake-time component. The human cortisol response is modulated by circadian phase. Exposure to...

Exposure to light at night increases alertness, but light at night (especially short-wavelength light) also disrupts nocturnal physiology. Such disruption is thought to underlie medical problems for which shiftworkers have increased risk. In 33 male subjects we investigated whether short-wavelength attenuated polychromatic white light (<530 nm filt...

Purpose: To determine the influence of several factors on standard automated perimetry test results in glaucoma. Methods: Longitudinal Humphrey field analyzer 30-2 Swedish interactive threshold algorithm data from 160 eyes of 160 glaucoma patients were used. The influence of technician experience, time of day, and season on the mean deviation (M...

Light elicits robust nonvisual effects on numerous physiological and behavioral variables, such as the human sleep-wake cycle and cognitive performance. Light effects crucially rely on properties such as dose, duration, timing, and wavelength. Recently, the use of methods such as fMRI to assess light effects on nonvisual brain responses has reveale...

One of the most frequently investigated hypotheses of the pathophysiology underlying Seasonal Affective Disorder (SAD) is a disturbance of circadian rhythms. Since the circadian system as well as other non-visual effects is especially sensitive to blue light, a new light therapy device with blue enriched polychromatic light was tested for its effic...

The aim of the present study was to analyze the circadian rhythmicity in handwriting kinematics and legibility and to compare the performance between Dutch and German writers. Two subject groups underwent a 40 h sleep deprivation protocol under Constant Routine conditions either in Groningen (10 Dutch subjects) or in Berlin (9 German subjects). Bot...

To measure activity during sleep, polysomnography and actigraphy are often used. The DynaPort MiniMod measures movement intensity and body position day and night. The goal was to examine the validity of the DynaPort MiniMod in assessing physical activity and body posture during sleep. In Study A, 10 healthy participants slept with the DynaPort Mini...

The effect of artificial dawn during the last 30 min of sleep on subsequent dissipation of sleep inertia was investigated, including possible involvement of cortisol and thermoregulatory processes. Sixteen healthy subjects who reported difficulty with waking up participated in random order in a control and an artificial dawn night. Sleep inertia se...

The timing of work and social requirements has a negative impact on performance and well-being of a significant proportion of the population in our modern society due to a phenomenon known as social jetlag. During workdays, in the early morning, late chronotypes, in particular, suffer from a combination of a nonoptimal circadian phase and sleep dep...

Accumulating evidence suggests epilepsy and seizures may influence circadian rhythms and that circadian rhythms may influence epilepsy. It is also conceivable that seizure timing influences the timing of daily activities, sleeping, and wakefulness (i.e., chronotype). Only one group has studied the distribution of chronotypes of epileptics, showing...

We investigated the effects of sleep loss and circadian rhythm on number comparison performance. Magnitude comparison of single-digits is robustly characterized by a distance effect: Close numbers (e.g., 5 versus 6) produce longer reaction times than numbers further apart (e.g., 2 versus 8). This distance effect is assumed to reflect the difficulty...

Light is the signal that entrains the biological clock in humans to the 24-hour external time. Recently, it has been shown that short wavelengths play a key role in this process. In the present study, we describe a procedure to measure, objectively and in a quick way, the spectral composition of the light reaching the retina in vivo. The instrument...

Previous studies suggest circadian rhythm disturbances in children with attention-deficit/hyperactivity disorder (ADHD) and sleep-onset insomnia (SOI). We investigate here sleep and rhythms in activity and melatonin in adults with ADHD. Sleep logs and actigraphy data were collected during 1 week in 40 adults with ADHD, of whom 31 reported SOI. Sali...

Studies in humans and mice revealed that circadian phase shifting effects of light are larger at the beginning of a light exposure interval than during subsequent exposure. Little is known about the dynamics of this response reduction phenomenon. Here the authors propose a method to obtain information on the progression of phase during light exposu...

Humans show large inter-individual differences in organising their behaviour within the 24-h day-this is most obvious in their preferred timing of sleep and wakefulness. Sleep and wake times show a near-Gaussian distribution in a given population, with extreme early types waking up when extreme late types fall asleep. This distribution is predomina...

It is beyond doubt that the timing of sleep is under control of the circadian pacemaker. Humans are a diurnal species; they sleep mostly at night, and they do so at approximately 24-h intervals. If they do not adhere to this general pattern, for instance when working night shifts or when travelling across time zones, they experience the stubborn in...

Humans show large inter-individual differences in organising their behaviour within the 24-h day—this is most obvious in their preferred timing of sleep and wakefulness. Sleep and wake times show a near-Gaussian distribution in a given population, with extreme early types waking up when extreme late types fall asleep. This distribution is predomina...

Bright light can influence human psychophysiology instantaneously by inducing endocrine (suppression of melatonin, increasing cortisol levels), other physiological changes (enhancement of core body temperature), and psychological changes (reduction of sleepiness, increase of alertness). Its broad range of action is reflected in the wide field of ap...

In this paper we examine the relationship between melatonin suppression and reduction of sleepiness through light by comparing three different data sets. In total 36 subjects participated in three studies and received 4 h of bright light either from midnight till 4:00 hours (experiments A and B) or from noon till 16:00 hours (experiment C). In expe...

The mammalian retina contains both visual and circadian photoreceptors. In humans, nocturnal stimulation of the latter receptors leads to melatonin suppression, which might cause reduced nighttime sleepiness. Melatonin suppression is maximal when the nasal part of the retina is illuminated. Whether circadian phase shifting in humans is due to the s...

We report on results from an Internet survey of sleeping habits in a Dutch population using the Munich Chronotype Questionnaire (MCTQ), supplemented with the Horne-Ostberg Morningness-Eveningness Questionnaire (MEQ). The MCTQ was completed by 5,055 responders, of which 2,481 also completed the MEQ. MEQ score correlated well with the MCTQ assessment...

Sleep deprivation in humans results in sleepiness, decrements in performance, and changes in spectral parameters of electrical brain activity (EEG). Bright light at night counteracts sleepiness and influences spectral parameters of brain activity. The effects of bright light on performance and brain activity are less well studied during daytime tha...

Light can influence physiology and performance of humans in two distinct ways. It can acutely change the level of physiological and behavioral parameters, and it can induce a phase shift in the circadian oscillators underlying variations in these levels. Until recently, both effects were thought to require retinal light perception. This view was ch...

Objective: Nighttime bright light suppresses melatonin and reduces sleepiness. This reduction in sleepiness is associated with a reduction in the theta power of the Wake-EEG. Exogenous melatonin administration increases not only subjective sleepiness but also the theta power in the wake-EEG. This suggests that the reduction in sleepiness is mediate...