chapter 4 Flashcards
explain the sensations in the brina
it has no sensations
what do organs and senses do?
send out notifications to the brain
What is sensation?
detecting energy in the world and code it as neural signals our senses systemize and do the work
what is perception?
select, organize, and interpit the sensatoins
what is the thershold?
point where a change in stimuls can be detected (noticable differnce)
minimal value of a stimulus can be detected
absolute threshold
minimal value that can be detected within weight
difference threshold
what is the signal detection theory
to detect only stimulus is a dependent on stimulus intensisty, background noise, and random neural activity
what is below the threshold/?
subliminal stimuli
what frequency can we see with vision?
380-760 nm
liquid part of the eye between cornea and pupil
aqueous humor
what does the lens do
focuses the light on the retina
sphincter muscle that controls the shape of the eye
ciliary muscle
ability for the lens to take shape
accomidation
what does the pupil do
opening in the center of the eye that allows light to pass
what is the function of the iris?
2 bands of sphincter muscle that control the size of pupil, colored
what is the vitreous humor
gelatin inside the eye
what are floaters
debris in vitrious humor that cast a shadow on the eye
what is the retina
black surface of eye that is lined by photoreceptors (light is inverted upside down and backwards)
explain the fovea
(no rods) point of central focus, depression in retina, and center of macula
blind spot, place at which nerves and blood vessels enter and exit the eye
optic disk
explain rods
dim light, monocromatic, poor aquity-sharp, found in the perifery
explain cones
bright light, in color, good aquity, fovea
what happens when light hits the photoreceptors?
photo pigment breaks apart and stimulates the cell sending a messasge to bipolar cells the bipolar cells send it to the ganglion cells and it sends it to exit the eye at the optic disk
