Physiology of Light Flashcards
____ is the scientific study of functions and
mechanisms in a living system. As a sub-discipline of
biology, physiology focuses on how organisms, organ
systems, individual organs, cells, and biomolecules carry out
the chemical and physical functions in a living system
Physiology
What are some negative effects light has on us?
Eyestrain, headaches, dizziness, skin
cancer, and premature aging of skin and eyes
light affects our?
Biorythms, hormones, and behavior
____ _____ coordinates bodily functions for being awake and sleeping
Circadian Rythm
_____ ____ m is an internal body rhythm that
cycles approximately every 24 hours
Circadian Rhythm
Circa means?
about
Dia means?
Day
Our ___ _____ regulates our biological processes to allow our bodies to conserve resources.
Circadian Clock
_____ _____ is lighting that is designed to have a biological impact on the human circadian system
Circadian Lighting
Daytime napping can lead to?
The development of Parkinson’s later in life
________, a G family coupled receptor, found within the ganglion cell layer in the retina, plays an important role in non-image-forming visual functions, including hormone secretion, entrainment of circadian rhythms, cognitive and affective processes.
Melanopsin
What does ipRGCs stand for?
Intrinsically photosensitive retinal ganglion cell
______ ______ defines the Magnitude of Human Circadian Light
Melanopic Illuminance
WELL Building Standard has adopted melanopic lux in Feature ___ of their Light Concept.
L03
120, 150, 180, 240 vertical melanopic lux
for a minimum of 4 hours per day.
is what Well Building standard?
L03: Circadian Lighting Design
Fixtures have a luminance less than
10,000 cd/m2 between 45 °- 90° from
nadir, and/or an intensity of less than
1,000 candela between 45 °- 90° from
nadir. is what WELL building standard?
L04: Electric Light Glare Control
Problems related to circadian rhythms are
associated with
SAD (Seasonal Affective Disorder
_____ A condition associated with an individual’s
inadequate exposure to sunlight
SAD
Effects of _____: Depression, weight gain, lack of concentration, and sleeplessness
SAD
Dimentia sufferers affected by daylight change at
end of day can be defined as?
Sundowning
____ _____ successful in helping to regulate biological clock associated with circadian rhythm
Light therapy
How many people in the US have a visual impairment?
16 million
What does AMD stand for?
Age-related macular degeneration (AMD)
Decrease in eye’s elasticity and thickening of the lens.
Affects visual acuity and the ability to see objects at
close range
Are all symptoms of?
Presbyopia
_____ affects not only emotions but, cognitive
processes, memory, communication, and
perceptions
Light
according to Flynn what type of lighting do people prefer?
Warm and dim
___ reported a blue spectrum stimulates rods in the eyes
Rea
___ suggests bluer light should be used in workplace
Navvab
A proper amount of stimulation can?
Increase attentiveness
Reduce fatigue
Alter perceptions of time
Promote positive moods
Too much stimulation can cause?
anxiety and stress
These are all examples of?
Glare
Flickering
Unnatural light patterns
Noise
Color Distortions
Excessive stimulation from lighting
What are the 4 relationships that shape our understanding of where light is most effective?
- Adaptation
- Brightness
- Phototropism
- Vertical Vision
______ design becomes a study of contrast and placement rather than an application of even light levels throughout a space.
Lighting
High-noon sunglight is how many times brighter than full-moonlight?
tens of thousands
_____ is the subjected judgment of lighted objects in an environment
Brightness
____ is the product of contrast
Brightness
“____” objects only need to be brighter than their neighbors
Bright
Humans notice bright things and ignore dark things is?
Phototropism
Humans tend to notice what is right in front of them this is called?
Vertical Vision
What is a diurnal cycle?
any pattern that recurs every 24 hours as full rotation of the planet earth around its axis
What does CRSWD stand for?
circadian rhythm sleep–wake disorders (CRSWD)
SCN stands for?
suprachiasmatic nuclei
____ activity is also modulated by non-photic information via neurotransmitters and hormones such as serotonin [54] and melatonin [23], and from peripheral clocks in other tissues
SCN
What are the 3 types of cones differing in their preference for light at specific wavelengths
Long wavelenght senstive cones (L Cones)
Medium wavelength sensitive cones (M Cones)
Short wavelength sensitive cones (S Cones)
___ allow us to see color, spatial detail and motion at light levels typical for daytime
Cones
____ are suppressed at daytime light levels and only signal at light levels typical for twilight and darker
Rods
Rods are absent in the?
Fovea
Can rods distinguish colors?
Nope
What does RGCs stand for?
Retinal Ganglion Cells
What do RGCs do?
integrate information and
send it to the brain via the optic nerve—express the photopigment melanopsin
______ is a short-wavelength-sensitive pigment with a peak spectral sensitivity near
around 480 nm [4], rendering some RGCs intrinsically photosensitive
Melanopsin
