scispace - formally typeset
Search or ask a question

Belysning och hälsa - en kunskapsöversikt med fokus på ljusets modulation, spektralfördelning och dess kronobiologiska betydelse

About: The article was published on 2002-01-01 and is currently open access. It has received 5 citations till now.

Content maybe subject to copyright    Report

Citations
More filters
Proceedings ArticleDOI
01 Jan 2005
TL;DR: The result shows that the hardware design of the assessment system could be successfully used to experiment the relationship between the stimulus wavelength and the CFFT.
Abstract: Previous studies used fixed wavelength modulated light to demonstrate the relationship between critical flicker frequency threshold (CFFT) and the factors of the subjects. We address a method to assess the whole human visual spectral sensitivity curve (with the visible range of wavelength) to CFFT by frequency modulated light. The color sensitivity curve of three cones of human eyes is discussed as well as the hardware design of the assessment system is provided. The result shows that this system could be successfully used to experiment the relationship between the stimulus wavelength and the CFFT

11 citations


Cites background from "Belysning och hälsa - en kunskapsöv..."

  • ...Inter-individual variations are large for all methods [2]....

    [...]

  • ...Some results indicate a variation of the CFFT with the wavelength of the stimulus [2], with lower values for red than for green or white [2]....

    [...]

References
More filters
Journal ArticleDOI
TL;DR: It is concluded that maladaptation of the human circadian system to night work, with its associated decline in alertness, performance, and quality of daytime sleep, can be treated effectively with scheduled exposure to bright light at night and darkness during the day.
Abstract: Working at night results in a misalignment between the sleep–wake cycle and the output of the hypothalamic pacemaker that regulates the circadian rhythms of certain physiologic and behavioral variables. We evaluated whether such physiologic maladaptation to nighttime work could be prevented effectively by a treatment regimen of exposure to bright light during the night and darkness during the day. We assessed the functioning of the circadian pacemaker in five control and five treatment studies in order to assess the extent of adaptation in eight normal young men to a week of night work. In the control studies, on the sixth consecutive night of sedentary work in ordinary light (approximately 150 lux), the mean (±SEM) nadir of the endogenous temperature cycle continued to occur during the night (at 03:31 ±0:56 hours), indicating a lack of circadian adaptation to the nighttime work schedule. In contrast, the subjects in the treatment studies were exposed to bright light (7000 to 12,000 lux) at night...

531 citations

Book
01 Jan 1981
TL;DR: In this paper, the authors discuss the effect of lighting on the perception of spaces and objects, as well as the effects of age on the Circadian Timing System on real visual tasks.
Abstract: Fundamentals Light Introduction Light and Radiation CIE Standard Observers Photometric Quantities Some Limitations Colorimetric Quantities Sources of Light Control of Light Distribution Control of Light Output Summary Visual System Introduction Structure of the Visual System Continuous Adjustments of the Visual System Capabilities of the Visual System Perception through the Visual System Summary Non-Image-Forming System Introduction Some Physiology Circadian Timing System Characteristics of the Circadian Timing System Awakening System Pupil Size Problems and Potential Summary Generalities Lighting and Work Introduction Overview Light, Work, and the Visual System Light, Work, and the Non-Image-Forming System Light, Work, Mood, and Motivation Summary Lighting and Visual Discomfort Introduction Characteristics of Visual Discomfort General Causes of Visual Discomfort Specific Causes of Visual Discomfort Discomfort, Performance, and Behaviour Visual Discomfort and Lighting Quality Summary Lighting and the Perception of Spaces and Objects Introduction Simple Perceptions Higher-Order Perceptions Perception of Objects Summary Specifics Lighting for Offices Introduction Illuminance Light Sources for Office Lighting Lighting Systems Lighting Controls Summary Lighting for Industry Introduction Problems Facing Lighting in Industry General Lighting Localized and Task Lighting Visual Inspection Special Situations Summary Escape Lighting Introduction Escape Lighting in Context Operating Conditions Exit Signs Escape Route Lighting Special Situations Escape Lighting in Practice Summary Lighting for Driving Introduction Vehicle Forward Lighting Vehicle Signal Lighting Road Lighting Markings, Signs, and Traffic Signals Summary Lighting for Pedestrians Introduction What Pedestrians Want from Lighting Lighting Criteria Lighting for Safe Movement Lighting for Security Lighting, Comfort, and Attraction Completing the Picture Summary Lighting and Crime Introduction Some History Lighting as a Crime Prevention Measure The Reason Why Essential Characteristics of Lighting Special Situations Generalization and Value Summary Lighting for the Elderly Introduction Optical Changes with Age Neural Changes with Age Vision Loss Effects of Age on Visual Capabilities Effects of Age on Real Visual Tasks Effects of Age on the Circadian Timing System What Can Be Done to Offset the Effects of Age? Summary Light and Health Introduction Light as Radiation Light Operating through the Visual System Light Operating through the Circadian Timing System Unresolved Issues Summary Light Pollution Introduction Forms of Light Pollution Causes of Light Pollution Consequences of Light Pollution Reactions to Light Pollution Limiting Light Pollution The Future Summary Lighting and Electricity Consumption Introduction Legal Status Trends in Lighting Regulation Trends in Lighting Recommendations Design Load Shedding Summary The Way Ahead Introduction Background Problems with New Technology Problems with New Knowledge Problems with Increased Pressure Research Approaches New Tools Evaluating Research Summary References Index

375 citations

Journal ArticleDOI
TL;DR: Morning light phase-advanced the dim-light melatonin onset and was more antidepressant than evening light, which phase-delayed it, which should help establish the importance of circadian time of light exposure in the treatment of winter depression.
Abstract: Background: According to the phase-shift hypothesis for winter depression, morning light (which causes a circadian phase advance) should be more antidepressant than evening light (which causes a delay). Although no studies have shown evening light to be more antidepressant than morning light, investigations have shown either no difference or morning light to be superior. The present study assesses these light-exposure schedules in both crossover and parallel-group comparisons. Methods: Fifty-one patients and 49 matched controls were studied for 6 weeks. After a prebaseline assessment and a light/dark and sleep/wake adaptation baseline week, subjects were exposed to bright light at either 6t o 8AM or 7t o 9PM for 2 weeks. After a week of withdrawal from light treatment, they were crossed over to the other light schedule. Dim-light melatonin onsets were obtained 7 times during the study to assess circadian phase position. Results: Morning light phase-advanced the dim-light melatonin onset and was more antidepressant than evening light, which phase-delayed it. These findings were statistically significant for both crossover and parallel-group comparisons. Dim-light melatonin onsets were generally delayed in the patients compared with the controls. Conclusions: These results should help establish the importance of circadian (morning or evening) time of light exposure in the treatment of winter depression. We recommend that bright-light exposure be scheduled immediately on awakening in the treatment of most patients with seasonal affective disorder. Arch Gen Psychiatry. 1998;55:890-896

323 citations


"Belysning och hälsa - en kunskapsöv..." refers background in this paper

  • ...Förekomsten av SAD och sub-SAD har kunnat dokumenteras i många olika studier, på norra halvklotet i bland annat Alaska, Danmark, England, Finland, Island, Norge, Saudiarabien, Schweiz, Skottland, Sverige och de centrala delarna av USA, och på södra halvklotet under deras vinter i Antarktis, Argentina, Australien och Sydafrika (77)....

    [...]

  • ...Dessa sjukdomstillstånd kallas med en engelsk fackterm ”seasonal affective disorder” (SAD) eller, om det rör sig om mildare besvär, ”subSAD”....

    [...]

  • ...Det finns också belägg för att regelbunden vistelse utomhus i naturligt dagsljus kan vara ett bra alternativ till ljusbehandling mot SAD (10; 31; 43; 83; 85; 118; 138)....

    [...]

Journal ArticleDOI
TL;DR: The widespread visual dysfunction reported here is more likely to be related to known pathological changes in primary visual and association cortex in AD than to changes in the retina or optic nerve.
Abstract: In patients with Alzheimer's disease (AD), compared with age-matched and young healthy control subjects, visual deficits in the following functions were observed: color, stereoacuity, contrast sensitivity, and backward masking (homogeneous and pattern). Critical flicker fusion thresholds were normal, relative to age-matched healthy subjects. For color, the majority of the errors were tritanomalous (blue axis). Color and stereoacuity deficits were unrelated to severity of dementia, in accordance with models of vision that describe these functions as modular rather than diffuse for cortical localization. Although contrast sensitivity was depressed throughout the frequency range in AD, more patients were impaired at low than at high spatial frequencies, contrasting with the observed normal aging pattern of high-frequency loss. Healthy elderly subjects showed depressed critical flicker fusion thresholds and reduced contrast sensitivity at high frequencies, relative to the young group; differences between these groups were not found for the other vision tests. A subset of the AD group received detailed neuro-ophthalmological examination, and no abnormalities were found. This finding, taken together with normal thresholds for critical flicker fusion, suggests that the widespread visual dysfunction reported here is more likely to be related to known pathological changes in primary visual and association cortex in AD than to changes in the retina or optic nerve.

322 citations


"Belysning och hälsa - en kunskapsöv..." refers background in this paper

  • ...Emellertid har man inte kunnat finna att CFF förändras av denna sjukdom (39)....

    [...]

Journal ArticleDOI
TL;DR: A significant reduction of shoulder pain was reported in the T and S groups in parallel with a significant reduction in static trapezius load, while no such reduction was found in the C group, two years after the intervention.

310 citations


"Belysning och hälsa - en kunskapsöv..." refers background in this paper

  • ...I en interventionsstudie bland kontorsarbetare av Aarås och medarbetare (1) minskade ögonbesvären signifikant genom att belysningsstyrkan i lokalen ökade från 300 till 600 lux....

    [...]

  • ...Building Research and Practice, 31(1), 32-38....

    [...]

  • ...Optometry and Vision Science, 75(1), 6268....

    [...]

  • ...Journal of Royal College of Physicians of London, 32(1), 27-35....

    [...]

  • ...Journal of the Illuminating Engineering Society, 21(1), 3-14....

    [...]