Tag Archives: circadian light

Healthy Lighting: Spotlight on Assisted Living

  1. Understanding of Circadian Lighting
    • Circadian light differs from the generally conceived definition of visual light in that it refers to the affect of lighting on the human circadian system, as opposed to light as a stimulus for the human visual systems.
    • Optimal functioning of the circadian timing system is imperative for good health and can be assisted with proper lighting systems. For appropriate designing of lighting and the associated SPD’s, we depend upon the Circadian Stimuli (CS) that each light offers. Simply defined, the light output or the light levels are not as important in this situation, as the CS factor of each light.
    • Humans have developed an endogenous timing system that optimally synchronizes physiology and behavior (e.g. rest/activity cycles)
    • The timing of our daily biological functions are organized and orchestrated by the master circadian clock. This is hosted by the suprachiasmatic nuclei (SCN) in the hypothalamus
    • The SCN orchestrates circadian rhythms in behavior and physiology via endocrine and neural pathways.
    • The Circadian System (“circa”, around; “dies”, day) has two fundamental characteristics:
      • Endogenous rhythmicity with a period of approximately 24 hours that persists independently of oscillations in external factors such as the light/dark cycle
      • The ability to have its timing shifted by external factors such as light and nutrient intake
    • The importance of the circadian system is exemplified by the observation that circadian disruption leads to an array of disorders (eg; sleep disorders, impaired glucose regulation & obesity) and decreased life expectancy
    • Specifying of dynamic white LED lighting that can be adjusted for higher Correlated Color Temperature (CCT) in the morning and lower CCT in the evening time that can assist in reinforcing the circadian rhythm.

 

  1. Architectural Lighting
    • By understanding how lighting can compensate for common changes that happen to the aging eye, designers can improve the quality of life of older adults in assisted living facilities. Some of those factors where lighting can be used to improve the quality of life:
      • Development of light levels to meet the IESNA recommended levels
      • All lighting to be provided with minimal source brightness. Glare control accessories to be provided where required.
      • The use of dynamic white LED lighting can allow the lighting to respond to the changes in the inhabitant’s environment.
      • Lighting to be provided with sustainable light sources such as LED and CFL to maximize energy efficiency and provide cost savings.
      • The selection of material finishes can increase the ability of the lighting to blend in with its architectural environment.
  1. The Portals of Light

This is a proprietary AWA design solution developed especially for Assisted Living spaces, but this solution also remains pertinent for Special Needs patients (Alzheimer’s, Dementia, Autism etc.)

  • Provides quality lighting design solutions for both circadian and architectural lighting in transition locations (vestibules, foyers, lobbies, etc.). This helps in reducing the jarring impact that change in light levels brings to the residents in Assisted Living spaces. This system comes with a plug-n-play modularity that can be moved easily. It can be used to retrofit existing locations, or used for new construction.
  • By improving the lighting in these transitional spaces, we can provide improved healthcare for all inhabitants, especially those who are not as mobile.

 

Sources:

  1. 2013 Fall; 7(1):60-78. Senior living environments: evidence-based lighting design strategies.
  2. RP-28-07. Lighting for the Visual Environment for Senior Living (ANSI Approved)
  3. Mariana G. Figueiro. 2001. Lighting the way: a key to independence. Lighting Research Center.
  4. M ariana G. Figueiro. 2013. A 24 Hour Lighting Scheme for Older Adults. Lighting Research Center.

Image Credit: Lighting Research Center (A 24 Hour Lighting Scheme for Older Adults)

Sleep Quality of Youth

Light triggers critical physiological and psychological responses within human beings. The level and quality of light within the built environment has real implications on our health and wellness as we become more aware of light’s implications on our health, we have a larger repertoire with which to impact a positive benefit on our health.

SLEEP DEPRIVATION

  • During the spring, late sunset and extended daylight exposure delays bedtime in teenagers
  • Increased exposure to early evening light delays the onset of nocturnal melatonin
  • Nocturnal melatonin: hormone that indicates to the body when it’s nighttime
  • Combine the delay in sleep with early school hours means many teens experience sleep deprivation, mood changes, increased risk of obesity and under performance at school

LRC CASE STUDY AT ALGONQUIN MIDDLE SCHOOL

  • 16 students were given a daysimeter – a small device to measure an individual’s exposure to daily “circadian light”
  • Circadian light: the potential for light to suppress melatonin synthesis at night not how light stimulates the visual system
  • Experienced a delay in melatonin onset by an average 20 minutes in the spring relative to winter

RESULTS:

  • Extended daylight hours due to the seasonal change, not evening electric lighting, had the biggest impact on delayed sleeping patterns
  • The melatonin delay caused an average of 16 minute delay in reported sleep onset and a 15 minute average reduction in reported sleep duration during the spring
  • The lrc recommends that teenagers increase morning daylight exposure throughout the year and decrease evening daylight exposure during the spring months