Chapter 5 Light & Health
What are some risks attributed to light exposure?
"Studies indicate rotating-shift working women have a greater probability of contracting breast cancer than day-shift women possibly due to exposure to light at night and/or circadian disruption."
What were sleep patterns prior to electric light?
- 4 hours "first sleep" - 1-3 hours "quiet wakefulness" - 4 hours "second sleep"
What are some positive psychological effects of illumination?
- Subjective responses - Personal vision attributes - Context of the situation - Design elements of the space - Type of light source - Directional qualities of light
What conditions can blue light treat?
- sleep disorders - SAD (seasonal affective disorder) - jet lag, - premenstrual syndrome - Jaundice in infants
When did Edison Patent the incandescent light
1879
When was melanopsin discovered
1998
What is melatonin
A light sensitive hormone produced by our bodies in the evening.
What effect does light and vitamin D it provides help us?
Absorption of calcium prevents osteoporosis and rickets.
What are the physiological effects of lighting?
Affects circadian rhythm, light therapy, Blue light
What suppresses the level of melatonin?
Any light hitting the retina
How can blue light affect us
By elevating body temperature, heart rate and reducing sleepiness.
What is it called when light helps to regulate your biological clock?
Circadian rhythm
How are UV lights used?
Cures jaundice in infants.
How does your body respond to red & blue light?
EEG rhythmic activity changes
What suggestions did she make in her study?
Eliminate bright florescent lights above beds, to avoid disturbing residents.
Person Physical/biological (health) relates to
Environmental aspects Physical (natural and built)
Person Psychological (Self-esteem)
Environmental aspects Interpersonal (friends, spouse)
Person Sociocultural (role as worker)
Environmental aspects Sociocultural (Home, Community, culture
How does your heart respond to Red & Blue light?
Exposure to high levels of red & blue light increases heart rate
Light therapy can be used treat?
Forms of cancer - Sleep disorders - Skin disorders (psoriasis, eczema) - Pain management - Wound healing - Depression - SAS}D
What are other psychological factors caused by light?
High-contrast lighting can emphasize and enhance emotional responses.
What are some psychological factors caused by light?
Illumination can alter behavior and can elicit subjective impressions of the environment.
How does blue light help us?
Improves alertness and performance in the workplace. We tend to have better memory and cognitive function. Improves nighttime sleep (when exposure is during the day).
What effects does the interruption of of circadian rhythm cause?
It affect performance and our health by contributing to various disorders.
How did this change in lighting help residents?
It didn't wake up patients when nurses came into the room. It made them more comfortable when they went into bathroom at night.
How does melatonin affect us?
It promotes sleep and alerts our biological processes to the approximate time of day.
How does blue light effect melatonin?
It reduces natural melatonin levels.
How is your circadian rhythm regulated?
Light exposure regulates our body's circadian rhythms, which includes the sleep/wake cycle Our biological clock synchronizes with cycles of daylight and darkness
What is your circadian rhythm insensitive to?
Long-wavelength light - red-light
What did she replace the florescent lights with
Motion sensor controlled amber LED lights.
Physical environment influences?
Our Well being on many levels
What is Melanopsin?
Photoreceptor in the eye (along with cone and rods)
What is the study Dr. Maraina Figueiro did?
Senior Health Care Facility
What is your circadian rhythm sensitive to?
Short-wavelength light - blue light
What does quality lighting affect
The person-in-environment system
What is Photomedicine?
The science dedicated to using light to improve human health.
What kind of effects can lighting have on your health?
There are positive and negative effects that affect health, behavior and the psychological well-being of people
What are the effects of too much blue light?
Too much light at the wrong time can frustrate your body's ability to go to sleep.
What are symptoms of Melanopsin?
Uniquely sensitive to blue light • Provides signals to the brain's master clock - aka, circadian rhythm • Regulates production of melatonin • Blue light has strong effect on sleep cycles on blind persons
How do we inadvertedly change or circadian rhythm?
With illumination - the use of electric light.
How was circadian rhythm regulated before electrical lighting?
With the rising and setting of the sun.
What can the physiological effects of lighting affect in your life
Workplace performance Daylighting
How does blue light influence biological functions?
hormone secretion - heart rate - alertness - sleep propensity - body temperature - gene expression
Details about evidence based design can be found where?
www.informedesign.umn.edu