Sensation and Perception Flashcards
Absolute threshold
the minimum stimulation for a stimulus to be detected
vision - 30 miles
hearing - 20 ft
taste - two gallons of sugar per tbs
smell - 10 parts/billion
touch - 0.0004 grams of pressure
Just noticeable difference
the smallest detectable change that can be detected 50% of the time
Weber’s law
our sensory system is sensitive to detecting proportional differences not absolute differences
Sensory adaptation
sensory receptors stop physically responding to a constant stimulus
Opponent process theory
when our system is over stimulated in one direction, it becomes hypersensitive to opposing stimuli as it attempts to regain its balance
Top down processing
sensory input is organized according to prior knowledge and expectations
bottom up processing
perception is built from raw sensory input with meaning emerging gradually as the brain processes details without relying on prior knowledge
Muller-Lyer illusion
monocular depth cues are weaker or nonexistent among people raised in cultures without carpentry or architecture
The Hermann Grid
nearby neurons suppress each other’s activity to enhance contrast
Multi sensory integration
When its noisy, you understand people better when you can see their lips
Cataracts
clouding of the lens, making vision blurry
Glaucoma
damage to the optic nerve due to increased pressure
Macular Degeneration
foveal damage leads to loss of central vision
Diabetic Retinopathy
Blood vessel damage in the retina, high blood pressure damages blood vessels
Noise-induced hearing loss
hair cells in the cochlea die, can lead to tinnitus (persistent ringing)
Presbycusis
age related hearing loss
Heart damage due to excess sugar
too much sugar in the bloodstream and high insulin levels lead to increased risk of heart disease
Liver damage due to excess sugar
causes fast rise in blood sugar that can overwhelm the liver leading to fatty liver and cirrhosis
Joint damage due to excess sugar
Lead to inflammation which can worsen join pain and eventually lead to arthritis
Cross-sensitization
abnormally high dopamine spikes caused by alternative dopamine spiking sources like nic
- Once you become addicted to something you are more likely to become addicted to other drugs
Rods
Optimized for night vision, black and white light sensitivity, located in the periphery of the retina
Cones
Optimized for daylight vision, color, acuity, and fine detail, concentrated in the fovea
Stare at a color lone enough, cones for that color become tired, so the color becomes duller, and the contrasting color becomes more emphasized
Cornea
fixed lens on the outer surface of the lens
Pupil
a hole
