perception midterm 3 Flashcards
cues
pieces of information available in the external world
oculomotor depth cues
cues that come from the muscles in and around our eyes that help us to perceive depth
accommodation
when the lens on the eye changes shape to focus the eye, it can tell us whether we are looking at something closer or farther away
- gets fatter for closer objects
convergence
muscles around the eye will tell you whether you are looking at soemthing nearby or far away based on if the eyes are mvoing inwards or outward
monolular depth cues
depth cues that we can see even with only one eye
types of monocular depth cues
- pictorial
occlusion
relative size
familair size
atmospheric perspective
movement cues (motion parallax, delection and accretion)
pictorial cues
cen depict depth even when just looking at a 2D image
occlusion
when one object gets in the way of another object you can tell that the one in front is closer to you than the one being covered which is further away
- tells us relative distance not actual distance
relative size
when there are multiple of the same objects with the same size that look like they are different sizes we know that that just means the larger one is closer to us and the smaller one is further away
familiar size
when we use our prior knowledge of an object to tell whether it is close or far away, like if a quarter and a dim look the same size we know that the dime is closer to use than the qaurter
atmospheric perceptive
distant objects are less clear to us because we are looking through more air whereas something closer is much sharper
motion parallax
nearby objects appear to be moving faster than further away objects
delection and accretion
when you are looking at somehting while moving and one object disappears or reappears in your vision you know that it is further away than what was abstructing your vision
binocular disparity
the difference bewteen the image on the left retina than the right
Wheatstone’s stereoscope
created a sense of depth by putting together 2 slightly diffrent photos of the same scene, like two cameras taking the same picture a few inches apart
stereopsis
an impression of depth
- your brain compares the images seen from your right and left eye and use the difference to infer depth
corresponding points
pair of points that would overlap if yo slid one retina on top of the other
object of interest
location of object of interest determines how eyes converge so image of objects fall on EACH fovea
horopter
imaginary cicle that passes trhough the “point of fixation”
physiology of depth percpetion
neurons called binocular depth cells or disparity -selective cells respond to specific degrees of disparity
- if theres not disparity then the two images on the retinas are not lining up
head crusher
failsto experience size constancy - only notices retina size - so assumes his fingers and dudes head are same distance away
retina image size
as a person walks away the size of their image gets smaller but your perception of thier distance gets larger
size constancy
when we correctly perceive objects physical size to remain constant despite varying distance and retina image size
size-distance scaling
taking objects distance into account wshen estimating its physical size
