Textbook Notes (363,127)
Canada (158,212)
Psychology (9,569)
PSYB51H3 (301)
Chapter 3

Chapter 3 Notes

7 Pages
Unlock Document

University of Toronto Scarborough
Matthias Niemeier

Chapter 3: Spatial Vision: From Stars to Stripes Visual system in cerebral cortex translate images into stripes From Primary visual cortex we separate into Where and What Flow of info for form and colour Retinal ganglion cells Thalamus LGN Primary visual cortex visual association cortex Higher-order visual assoc. cortex Visual Acuity: Oh Say Can You see? Contrast: The difference in luminance btw an object and background or lightdark parts Acuity: smallest detail we can see o For scientists, smallest visual angle of cycle we can see Cycle: one rep. of black and white stripe Visual angle: Angle subtended by an object at the retina o angle from top and bottom of object onto center of lens and onto retina Fig 3.3 p. 53 we can see one cycle of 2mm at about 1 minute of arc (0.017) o this is limit is bc of spacing of photoreceptors Sine wave gratings: grating with a sinusoidal luminance profile o e.g. fig. 3.4 p. 54 o If cycle falls on separate cones, we can make out grating o When cycle falls onto one cone we see gray field or aliasing Aliasing: see cycles as longer than they really are Cones are separated by 0.5 min of arc (0.008) why we need 2 cones to see cycle Acuity in peripheral worse bc rods and cones are packed less tightly there A Visit to the Eye Doctor Snellen invented 2020 system of measuring acuity Letters are 5 times larger than strokes 2040 means distance person can see letters distance normal vision can see letters o E.g. 2040 means you have to be at 20 ft. to see letters ppl can see at 40 ft. If you can read 2020 latter you can see detail that subeneds 1 min of arc Most healthy adults have acuity of 2015 Acuity for Low-Contrast Stripes Spatial frequency: # of cycles of a grating per unit of visual angle o E.g. Visual angle btw each pair of white stripes is 0.25. Therefore spatial frequency is 10.25 = 4 cycles per degree www.notesolution.com
More Less

Related notes for PSYB51H3

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.