ArticlePDF Available

Fluorescent lighting, headaches and eyestrain

Authors:

Abstract

The weekly incidence of headaches among office workers was compared when the offices were lit by fluorescent lighting where the fluorescent tubes were operated by (a) a conventional switch-start circuit with choke ballast providing illumination that pulsated with a modulation depth of 43-49% and a principal frequency component at 100 Hz; (b) an electronic start circuit with choke ballast giving illumination with similar characteristics; (c) an electronic ballast driving the lamps at about 32 kHz and reducing the 100 Hz modulation to less than 7%. In a double-blind cross-over design, the average incidence of headaches and eyestrain was more than halved under high-frequency lighting. The incidence was unaffected by the speed with which the tubes ignited. Headaches tended to decrease with the height of the office above the ground and thus with increasing natural light. Office occupants chose to switch on the high-frequency lighting for 30% longer on average.
... Participants from eight studies investigating the effect of artificial lighting had outside view [34,37,61,66,78,90,96,102], when also including the diverse category. An online record [45] and one online study [63] were not included since the assessments were not about the participants' space. ...
... Only 17 studies reported the use of any shading device. Twenty-nine studies focused on artificial lighting, did not have shading devices due to windowless experimental settings [30,32,35,37,40,43,45,[47][48][49]54,55,59,63,64,67,68,70,72,74,75,78,80,82,84,86,88,96,97]. When considered, shading devices were mostly internal. ...
... The spectral composition of the light was used in two studies [75,81] identified under the category spectral power distribution (SPD). Even though the type of ballast is a feature of the luminaires, two studies [87,96] used it for flicker control, which was considered as another category of the predictors (Flicker). ...
Article
Full-text available
This paper presents a critical review of studies addressing the effects of window views, daylighting, and lighting on occupant behavior, perception, performance, and well-being. A systematic search in the Scopus database was performed in November 2021 and yielded 515 hits. Seventy-six studies were selected according to the following criteria: i) papers presenting research results with participants' responses and ii) accounting for daylighting, lighting, or window view assessments. The study and setting features, participants, predictors and outcomes, the statistical approach, the reported significance level, and study limitations were extracted from each paper. The analysis then identified differences in the effect of the predictor on the outcome. The number of records obtained through the structured analysis was 240. A wide range of predictors have been used in indoor daylighting, lighting, and window view research to assess people's responses. The most commonly used predictors were artificial lighting features and window features -qualitative predictors - followed by some properties of the light sources, such as correlated color temperature, spectral distribution and horizontal illuminance. Differences in the methods for data collection, the used predictors, the outcomes, and the ways to measure the outcomes generated inconclusive results or results that were limited to the specific study. We extracted data from selected studies to suggest a simple model for the prediction of occupant performance from illuminance and correlated color temperature. The data points were few and scattered and the model, therefore, suffers from considerable uncertainties. Yet, it quantifies performance effects in ranges that are comparable with similar models from other indoor environment domains.
... Cortical hyperexcitability may make those with migraine and other headache disorders more sensitive to visual stimulation such as flickering lights (Wilkins et al., 1989) and striped patterns (Harle et al., 2006). Such stimuli induce visual distortions and eyestrain and are also trigger stimuli for some individuals (Wilkins, 1986(Wilkins, , 1995Wilkins et al., 1979Wilkins et al., , 1980. ...
... Such stimuli induce visual distortions and eyestrain and are also trigger stimuli for some individuals (Wilkins, 1986(Wilkins, , 1995Wilkins et al., 1979Wilkins et al., , 1980. Flickering light sources up to around 100 Hz are problematic, and those working under flickering fluorescent lighting experience more headaches and other symptoms than those working in natural light or under high-frequency fluorescent tubes (Wilkins et al., 1989). Of greater interest here are the visual distortions and discomfort resulting from striped stimuli. ...
Article
Full-text available
Excessive sensitivity to certain visual stimuli (cortical hyper-excitability) is associated with a number of neurological disorders including migraine, epilepsy, multiple sclerosis, autism and possibly dyslexia. Others show disruptive sensitivity to visual stimuli with no other obvious pathology or symptom profile (visual stress) which can extend to discomfort and nausea. We used event related potentials (EPRs) to explore the neural correlates of visual stress and headache proneness. We analysed ERPs in response to thick (0.37 c/deg), medium (3 c/deg) and thin (12 c/deg) gratings, using mass univariate analysis, considering three factors in the general population: headache proneness, visual stress and discomfort. We found relationships between ERP features and the headache and discomfort factors. Stimulus main effects were driven by the medium stimulus regardless of participant characteristics. Participants with high discomfort ratings had larger P1 components for the initial presentation of medium stimuli, suggesting initial cortical hyper-excitability that is later suppressed. The participants with high headache ratings showed atypical N1-P2 components for medium stripes relative to the other stimuli. This effect was present after only repeated stimulus presentation. These effects were also explored in the frequency domain, suggesting variations in inter-trial theta band phase coherence. Our results suggest that discomfort and headache in response to striped stimuli are related to different neural processes, however more exploration is needed to determine whether the results translate to a clinical migraine population.
... 92,94 This triggers a chain of sensory and neural responses which, particularly in the case of long-term exposure, have been associated with visual fatigue, eyestrain, excessive eye movements, reduced visual performance and headaches. 92,[94][95][96][97] People with good vision and health can still be sensitive to flicker above critical flicker frequency. 92 However, flicker sensitivity varies between individuals: people suffering from headaches or migraines, autism or photosensitive epilepsy are more likely to be affected; flicker can also be a concern in case of reading tasks and tasks involving the use of screens. ...
... High frequency control gear (operating at 20 kHz or more) reduces the effects of flicker. 1,3,95,151 LED light sources powered directly from an AC supply are prone to flicker due to their rapid response to current fluctuations. Most LED lamps use high frequency drivers that convert the AC component of the mains supply into a DC output that produces a reduced light output modulation and thus helps to reduce flicker. ...
Article
Typical home lighting practice is mainly centred on visual aspects to enable safe movement between spaces, flexibility in multiuse spaces, a sense of aesthetics and energy efficiency. Whilst lighting impacts on the health of residents have not received similar consideration, this area is gaining increasing interest. This is even more important and actual in the context of the recent pandemic where people have been working or studying from home. A combination of bright daytime light and night-time darkness is essential for circadian entrainment and maintenance of a regular daily sleep–wake cycle, whereas exposure to light at night can negatively impact circadian rhythms and sleep patterns and ultimately lead to potential health problems. Additionally, lighting also has the potential to affect health through associated effects such as flicker, glare, optical hazards or electromagnetic fields. This article discusses the main areas of concern related to home lighting and outlines general recommendations to limit detrimental effects and contribute to good health.
... Light intensity may vary depending on the position of tanks in the rack or room, or may be reduced to inhibit algal growth (Bhargava, 2018). In addition, most artificial light fluctuates with low intensity (incandescent bulbs) or with a pronounced flicker (fluorescent and LED bulbs) (Inger et al., 2014) that can cause headaches and eye fatigue in humans (Wilkins et al., 1989), affect mate choice in captive birds (Evans, Cuthill & Bennett, 2006) and induce myopia in mice (Yu et al., 2011). Despite the potential for these factors to affect behaviour, experimental results, and reproducibility (Adatto, Krug & Zon, 2016;Sabet, van Dooren & Slabbekoorn, 2016a;Gerlai, 2018), light source and intensity are rarely reported in the literature. ...
Article
Full-text available
Globally, millions of zebrafish (Danio rerio) are used for scientific laboratory experiments for which researchers have a duty of care, with legal obligations to consider their welfare. Considering the growing use of the zebrafish as a vertebrate model for addressing a diverse range of scientific questions, optimising their laboratory conditions is of major importance for both welfare and improving scientific research. However, most guidelines for the care and breeding of zebrafish for research are concerned primarily with maximising production and minimising costs and pay little attention to the effects on welfare of the environments in which the fish are maintained, or how those conditions affect their scientific research. Here we review the physical and social conditions in which laboratory zebrafish are kept, identifying and drawing attention to factors likely to affect their welfare and experimental science. We also identify a fundamental lack knowledge of how zebrafish interact with many biotic and abiotic features in their natural environment to support ways to optimise zebrafish health and well-being in the laboratory, and in turn the quality of scientific data produced. We advocate that the conditions under which zebrafish are maintained need to become a more integral part of research and that we understand more fully how they influence experimental outcome and in turn interpretations of the data generated.
... Many different jobs and tasks that require attention and high perception are performed at desks and/or computers in offices. Studies on the mental and physical conditions of office workers who spend a long time indoors and cannot benefit directly from daylight have shown that the resulting effects range from loss of workforce and making critical mistakes [1][2][3]. For an efficient work area lighting application, both meeting vision needs and continuity in lighting come to the fore as an important requirement. ...
Article
Full-text available
Today, under the conditions where the number of office workers and artificial lighting applications have increased, although the effects of the Photometric Flicker phenomenon are serious, it is an issue that has not been understood in detail and people are not aware of it. Photometric Flicker phenomenon, which is a direct result of using ballasts or drivers with low power factor and lacking the necessary filtering features; It causes results such as decreased visual performance, loss of attention and perception. Considering that the conversion of LED luminaires is still not completed in many office buildings in the country, it is seen as an important requirement to investigate the Flicker effect in interior spaces that are considered to offer similar lighting levels and conditions, and to make a concrete due diligence by correlating this with the average age of office workers. For this reason, in this study, various tests and experiments were carried out with volunteer participants aged 18-30, 31-45 and 46 years of age and older without any significant vision problems, and the outputs of these studies were aimed to shed light on the relationship between age and lighting conditions. Keywords: Photometric Flicker, Interior lighting, Age and lighting relationship, Disruptive effects in lighting
... The literal meaning of photophobia is fear of light (1), but this is an oversimplification of the experience of migraine sufferers. In migraine, both headache and behavioural evidence of aversion can be provoked in response to four categories of retinal stimulation: bright light (2), flickering light (even when the flicker is too rapid to be seen [3]), patterns (4)(5)(6) and colour (7)(8)(9). The mechanisms may differ during and between acute attacks where headache is manifest. ...
Article
Visual discomfort is related to the statistical regularity of visual images. The contribution of luminance contrast to visual discomfort is well understood and can be framed in terms of a theory of efficient coding of natural stimuli, and linked to metabolic demand. While color is important in our interaction with nature, the effect of color on visual discomfort has received less attention. In this study, we build on the established association between visual discomfort and differences in chromaticity across space. We average the local differences in chromaticity in an image and show that this average is a good predictor of visual discomfort from the image. It accounts for part of the variance left unexplained by variations in luminance. We show that the local chromaticity difference in uncomfortable stimuli is high compared to that typical in natural scenes, except in particular infrequent conditions such as the arrangement of colorful fruits against foliage. Overall, our study discloses a new link between visual ecology and discomfort whereby discomfort arises when adaptive perceptual mechanisms are overstimulated by specific classes of stimuli rarely found in nature.
... Visually, daylight and views may shape perceptions of indoor environmental quality with outsized influence, given that the visual system dominates cognitive processes in both real-time and recall (Stokes and Biggs, 2014). Daylight impacts visual comfort, with small, too few, or occluded windows leading to fatigued and strained eyes (Simonson and Brozek, 1948;Cowling et al., 1990) and depriving occupants of a long-distance view, which can provide a point of relaxation for the eye's muscles (Wilkins et al., 1989). Expansive windows that let in too much daylight, on the other hand, can create the potential for glare and shadowed task areas that lead to excessive visual contrast (Hopkinson, 1971). ...
Article
Full-text available
While buildings are designed with expansive windows to allow for abundant daylight and views, in practice, they are frequently occluded to control for heat and glare. Electrochromic glass windows are a solution designed to maximize occupant access to daylight and views throughout the day, and previous research has demonstrated the benefits they can impart on sleep and cognition. We extend this research to quantify its impacts on the perceived physical and emotional wellbeing of occupants in an office environment. 30 office workers spent 5 days working in each of two West-facing offices that were identical with the exception of the window treatment: one with dynamic electrochromic windows and the other with functionally standard windows partially occluded by a fixed roller shade. When working in the office with electrochromic glass, participants were 8-fold more likely of report satisfaction with daylight conditions and 6.5-fold more likely to report satisfaction with views of the outside, were 48% less likely to report eyestrain, perceived a significant benefit to positive affect and were 77% less likely to report feeling depressed. This study adds to the growing body of research demonstrating the importance of daylighting strategies in designing spaces that support the physical and mental health of occupants.
Article
Flicker has been an important lighting system consideration for over a century. More precise terms are temporal light modulation (TLM) as the stimulus, and responses to TLM as the unwanted visual, cognitive, or physiological consequences. As lighting technology evolved, different forms of TLM emerged, and so did responses to them. Today, some LED systems – encompassing the LED, driver, and control – can result in TLM causing severe unwanted effects, while other LED systems produce no unwanted effects at all. LED systems can deliver a much wider range of luminous waveforms than conventional lighting systems, some exhibiting very high modulation depths. More than any light source before, they can elicit perceptions of the phantom array. Direct flicker effects at modulation frequencies less than about 80 Hz and the stroboscopic effect at frequencies greater than 80 Hz are fairly well understood, but the phantom array effect needs more exploration and characterisation. This review focuses on the technology and research history that led to current metrics for quantifying TLM and human responses to TLM. Visually impaired individuals may exhibit alterations in their response to TLM, but such a discussion is beyond the intent of this review. Thus, the focus is on individuals with normal visual function.
Chapter
In this chapter we review studies in which precision tints have been used in a variety of neurological disorders, including photosensitive epilepsy, autism, migraine, cluster headache, visual snow, stroke, multiple sclerosis and concussion. Whilst the evidence regarding these topics is preliminary and indicative rather than conclusive, the effects of coloured filters in these conditions may help to further elucidate the mechanisms underlying the benefit from colour. In particular, the extent to which these findings provide convergent support for the cortical hyperexcitability hypothesis is discussed.
Article
Objective: In this narrative review, we summarize clinical and experimental data on the effect of light in migraine and discuss future prospects. Background: Effective nonpharmacological treatment of hypersensitivity to light in migraine is an unmet clinical need. Current management strategies primarily consist of seeking a dark room and avoiding light exposure. Advances in the past 2 decades have improved our understanding of the underlying pathophysiology of how migraine is influenced by light. This may provide promising avenues for novel approaches in clinical management. Methods: We searched MEDLINE for articles published from database inception up to September 1, 2021. We used the search term "migraine" with the search terms "light," "photophobia," "treatment," "trigger," "circadian rhythm," "environment," and/or "pathophysiology." Results: Light is commonly reported as a trigger factor of migraine attacks, however, early manifestation of photophobia and false attribution is likely the actual cause based on data deriving from retrospective, prospective, and experimental studies. The most common photophobia symptoms in migraine are exacerbation of headache by light and abnormal sensitivity to light with the underlying neural pathways likely being dependent on ongoing activity in the trigeminovascular system. Clinical studies and experimental models have identified mediators of photophobia and uncovered narrow wavebands of the light spectrum that may reduce pain intensity during a migraine attack. Consequently, novel devices have undergone exploratory clinical trials with promising results. Conclusion: False attribution is likely the reason why light is commonly reported as a trigger factor of migraine attacks, and a prospective confirmation is required to prevent unnecessary avoidance. The observation that individuals with migraine are not equally photophobic to all wavebands of the light spectrum opens the potential for innovative pain management strategies. In this context, using human-centric lighting (also called integrative lighting) to mimic the natural daylight cycle and avoid harmful wavebands through modern technology may prove beneficial. Future research should identify direct and indirect consequences of light and other environmental factors in migraine to fill out knowledge gaps and enable evidence-based care strategies within institutions, work environments, and other settings.
Article
Full-text available
The successive lines of printed text form a pattern of ‘stripes’. The spatial characteristics of this pattern have been measured and found to be similar to those of patterns that induce discomfort, anomalous visual effects and even seizures. It is argued that reading provokes ‘eye-strain’ and seizures because of the striped properties of text, and that it is for this reason that headaches and seizures are reduced by covering the lines of text above and below those being read. In studies in which subjects are asked to judge the clarity of text it is shown that judgements of clarity are affected by the spatial characteristics of the pattern, in particular, the spacing between the lines. The average area of the page occupied by a letter (i.e. the product of the separation between the lines and the mean horizontal spacing between the centres of letters) accounts for less variance than does the separation between the lines of text. Within the constraints of conventional typography, the clarity of text could perhaps be improved without increasing costs by reducing slightly the typical spacing between the letters in order to increase the spacing between the lines.
Article
Full-text available
The size of eye movements across text was measured under conditions in which the text was illuminated by fluorescent light or was displayed on the screen of a cathode-ray tube. Under these conditions of intermittent illumination the high-velocity saccadic eye movements were enlarged. The extent to which they were enlarged depended on the frequency of intermittency, but was generally equivalent to the width of one letter. This disturbance of ocular motor control by intermittent illumination might help to explain why reading is generally slower on computer display terminals than with printed text.
Article
Full-text available
Certain patterns of stripes are judged to be unpleasant to look at. They induce illusions of colour, shape and motion that are sometimes perceived predominantly to one side of fixation. People who suffer frequent headaches tend to report more illusions, and if the pain consistently occurs on the same side of the head the illusions tend to be lateralized. The parameters of the patterns that induce illusions (including their shape, spatial frequency, duty cycle, contrast and cortical representation) closely resemble those that elicit epileptiform electroencephalographic abnormalities in patients with photosensitive epilepsy. The viewing conditions under which such abnormalities are likely to appear are also those under which more illusions are seen.
Article
The factors influencing flicker sensitivity are reviewed. Sensitivity is increasing because of improving lighting standards and personal peak sensitivity occurs for people approximately 20 years old. There is wide variability between people and the effect of flicker is related to the individual threshold. Office surveys reveal that significant numbers of people see flicker and that this feature is associated with the 'unsatisfactory' ratings of the lighting. Some headaches and eyestrain are related to seeing flicker. Light modulation from fluorescent lamps at 50 and 100 Hz has been measured and the growth in the 50 Hz component with time has been studied. The 50 Hz component is the one which is normally seen. The lamp characteristics show this 50 Hz modulation to remain at a low value for the first 7-8000 hours operation and thereafter to rise more rapidly with operation. Planned lamp replacement is now essential.
Article
Cette expérience a été entreprise pour comparer les effets de deux éclairages fluoresceins aur la qualité d'exécution d'une tâche visuelle et aur la ‘ fatigue ’ que celle-ci provoque chez les sujets examinés. Cea deux éclairages étaient identiques sinon par la fréquence du courant d'alimentation des tube3. II découle, de cette expérience ot de l'analyse atatiatique de ses résultats, les faits suivants:(1) Les résultats des trois tests de ‘ fatigue ’ utilises — fréquence de fusion optique subjective, temps de réaction motrice simple et irrégularité rythmique — se sont modifiés davantage après travail sous éclairage fluorescent à 50 Hz que sous eclairage fluorescent à 100 000 Hz. Cette différence est statistiquement significative (p
1. EEG records and clinical observations were obtained from a population of 1264 subjects (age 15–45) comprising 1198 patients and 66 normal adult volunteers. In the clinical group 202 patients were diagnosed as suffering from migraine, using the criteria of Dow and Whitty (1947). The EEG records were analysed while resting and during controlled activation by flicker, as described by Golla and Winter (1959). The results of analysis and the clinical observations were correlated by computation of contingency.
Computer analysis (FFT) was performed of the interictal EEGs of 20 patients with migraine and of a matched control group of normal volunteers. The EEG was studied at rest and during periodic photic stimulation.Using a combination of parameters 55% of the patients with migraine could be scored as abnormal vs. 5% of the control group. Moreover, an additional 20% of the patients with migraine showed abnormalities in the EEG on visual inspection which could not be expected to be found with this form of computer analysis.RésuméUne analyse par ordinateur a été exécutée sur les EEG inter-ictaux de 20 patients souffrant de migraine et chez des sujets d'un groupe de contrôle comparable au point de vue de l'âge. L'EEG était étudié pendant le repos et pendant la stimulation lumineuse intermittente.En utilisant une combinaison de paramètres, 55% des patients souffrant de migraine pourraient être considérés comme anormaux, à l'opposé des 5% du groupe de contrôle. De plus, l'interprétation visuelle des EEG de 20% des autres patients souffrant de migraine révélait des anomalies que l'on ne s'attendait pas à trouver avec cette méthode d'analyse par ordinateur.
Article
Fluorescent tubes flash at twice the mains frequency (100 Hz in Europe). With aging, 50-Hz brightness modulation appears. A survey of tubes used in our institute showed that 42% exhibited brightness modulation up to a depth of 20% or occasionally 30%. The effects of fluorescent lighting on the EEGs of 20 patients with photosensitive epilepsy have been studied. In no patient did the 100-Hz flicker of normally functioning tubes elicit paroxysmal activity. In 8 of 13 subjects sensitive to 50 Hz, IPS paroxysmal discharges were evoked by 50-Hz brightness modulation, but only at modulation depths of 50% or more. It is concluded that as paroxysmal activity could not be elicited by normally functioning tubes nor at those depths of modulation occurring in practice, fluorescent lighting is unlikely to present a hazard to photosensitive patients. Los tubos fluorescentes centellean al doble de la frecuencia de la red (100 Hz en Europa) aunque, con el uso, aparece una modulacion del brillo de SO Hz. Una revisibn de los tubos usados en nuestro Instituto mostro que el 42% demostraban una modulacion del brillo hasta una profundidad de un 20% y, ocasionalmente, de un 30%. Se han estudiado los efectos de esta luz fluorescente en los EEGs de 20 enfermos con epilepsyía fotosensible. La vibratión de 100 Hz de tubos funcionando normalmente, en ningún momento desencadenó actividad paroxística en estos enfermos. En 8 de 13 pacientes sensibles a 50 Hz IPS se evocaron descargas paroxísticas con una modulación del brillo del 50% pero solo con profundidades de modulación de 50% o más. Se concluye que la luz fluorescente raramente constituirá un riesgo para enfermos fotosensibles ya que no se ha podido desencadenar actividad paroxística mediante tubos funcionando normalmente ni en las profundidades de modulación que ocurren habitualmente.
Article
We have examined the spatial and temporal tuning properties of 238 cortical neurones, recorded using conventional techniques from acutely prepared anaesthetized cats. The authors determined spatial and temporal frequency tuning curves using sinusoidal grating stimuli presented to each neurone's receptive field by a digital computer on a cathode ray tube. The authors conclude from these results that areas 17 and 18 act in parallel to process different aspects of the visual information relayed from the retina via the lateral geniculate complex. Some or all of the differences between the areas may be attributable to the predominance of Y cell input to area 18 and the predominance of X cell input to area 17. The two areas seem reasonable candidates for the 'pattern' (area 17) and 'movement' (area 18) detecting mechanisms whose existence has been inferred from psychophysical experiments in both humans and cats.
Article
Single neurons in the cat visual system respond distinctly to the temporal information present in light from fluorescent tubes driven by 50 or 60 Hz alternating current. Despite the resulting flicker frequencies of 100 or 120 Hz all retinal and most thalamic neurons show strong phase locking of the neuronal responses to the modulation of fluorescent tube light. Some retinal ganglion cells have not yet reached their critical flicker fusion frequency under such conditions. Though usually beyond perception, the frequency and depth of modulation of artificial light thus might well play a role in biological light effects.