Class Notes (810,920)
Canada (494,377)
Psychology (6,045)
Prof (28)
Lecture 9

Lecture 9

7 Pages
Unlock Document

Western University
Psychology 2115A/B

Space Perception 10/24/2012 11:24:00 AM  Understanding how we perceive position of things in our environment  Important we have space perception i.e. If you don’t understand where the predator is that is chasing you, you won’t know how fast you need to run i.e. help so we don’t fall off cliffs i.e. hitting a baseball  Need to have an objective knowledge of how the real world is  Retinal mosaic  retina is like to a two dimensional mosaic (picture) of what we are seeing  Have to take the two dimensional brightness and colour and use that to figure out the appropriate space perception  Cones and rods are only able to give us this picture but we still manage to see three dimensional objects  Painters have an opposite problem they need to take the three dimensional and turn it into two  Di Vinci known for doing a good job at how various cues can be put into the canvas with the perception that there is a third dimension How does brain pick up on the third dimension?  Cues:  Muscular cues  Every time a desk looks at something they see the same thing the desk  Eye muscles seem reliable source of info  They are coming together and then moving apart  Convergence – angles and levels of accommodation you see the distance of something  Accommodation cue  (get info from text)  Convergence can serve as a cue up to 6 meters and beyond that is no good  monocular cues  (1) interposition o We can see differential distance o When something is blocking something else it give the illusion that it is one in front of the other [FIGURE 1]  (2) Retinal image size  how big is the thing on your retina? o i.e. dog example 6 dogs that degree in size as they go across and therefore sine they are the same distance form your retina there is no deferential differences, they are all the same distance, YET the perception is they are not the same distance  the dog of the lower numbers take up a larger part of your retina  not just retinal image size that matters. If you compare the small dog to the ball size they hold the same retinal size but the dog (6) looks farther then the ball  its NOT just retinal image size we know dogs are bigger then balls and so we calculate the familiar size  the size we know what things are  (3) linear perspective  as two parallel lines move away from you they get closer to you on your retina o as an artist can draw lines where the lines start large then move closer together give the illusion they are parallel but are reseeding in the distance  (4) texture gradient o i.e. pope looking down on the people the heads of the people in the front look bigger and are more spaced but as you move back it gets more tightly packed as you move back and appear smaller which gives us the idea of DEPTH  (5) height in the picture place o things that are closer to the horizon seem further away o [Figure 2] o could run a Stevens power law – for distance estimates  The n should bigger closer to the horizon o Galanter & Galanter, 1973  Things closer to the horizon gain depth, and distance faster  They found the n’s were exactly as mentioned before  N=1.2 and as you increase angle at the highest n=.8  Saw a decrease in n as it moved away from the horizon o This phenomenon is responsible of the moon illusion  If you look at the moon you find, when you see the moon close to the horizon it looks bigger then when it is up in the sky  (6) Shadowing o light usually is going down (from ceiling/ sky) o shadowing patterns give idea of depth and distance o the diagram in class the circles where it is the lightest at top and gradually gets darker it appears to be coming towards you o but the circles when the its brightest at the bottom and darker at top  created when the light hits the ground but doesn’t reach the stuff above it o  (7) Relative Brightness o closer you are to the object the more light will come off the object towards you o the farther you are the less light that is hitting your eye o therefore in picture if you want something that looks farther away you want to draw farther objects darker then closer objects  (8) Areal Perspective o look at something from a great distance there is something that
More Less

Related notes for Psychology 2115A/B

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.