intro

Question 1

how do we study visual perception?

Answer 1

1. physics, geometry
2. biology (neurophysiology)
   - optics, light, anatomy, physiology, cell function
3. visual arts
   - 3D representation, movies, painting, sculpture
4. medicine (patient case studies)
5. psychology (phenomenology, psychophysics)
   - psychophysics: relate a physical stimulus w a psychological state
6. computer vision (image understanding)
   - artificial intelligence, artificial visual systems (modelling the visual system to help understand it)

Question 2

what are recurring concepts of the course

Answer 2

1. adaptation or auto-calibration. our brain quickly adapts to the changing state of the world. for ex, vision from night to day, diverse situations need flexibility, motion
2. heuristics or rules of thumb. our brain uses shortcuts to solve computational complexities. when these shortcuts fail = illusion (rare)
3. bet on the familiar or non-accidental. we go w the most likely or most straightforward interpretation. ambiguous things can be interpreted in diff ways

Question 3

what do we know about light

Answer 3

• composed of photons (tiny packets of electromagnetic energy)
• light travels in a straight line
• light is an electromagnetic wave
• we see a very narrow range of the electromagnetic spectrum (400-700 nm)
• em energy can appear in diff forms determined by wl and each forms have their own em energy
• a photon’s wl is inversely proportional to its energy
• short wl = high energy = blue
• longer wl = low energy = red
• our main light source (sun) is in its peak output. the sun is also producing its em energy as the peak output corresponds to the narrow wl (visible light that we see)
• this kind of range of wl’s correspond more or less to the colours we see
• light and photons itself dont have colour (all a product of our brains)

Question 3

what is extramission

Answer 3

based on an old idea from ancient philosophers that we see by shooting light from our eyes which illuminates objects. intromission theory contrasts this in which we see bc objects reflect light which enters our eyes, triggering neural impulses that r interpreted by the brain as visual info

Question 4

explain pinhole optics/camera obscura

Answer 4

inverted image, how do we get an image

to recover the pattern, we need to selectively filter the input so that each point we receive light from only one direction. we need to filter that input w a pinhole camera. this was discovered by Ibn Al-Haitham

Question 5

what is refraction

Question 6

what are prisms

Answer 6

converging vs diverging

Question 7

what are lenses

Question 8

describe the eye structure and label it

Answer 8

sclera, cornea, lens, iris, pupil

Question 9

what are eye optics

Question 10

what is accommodation

Question 11

what is the retina

Question 12

what are photoreceptors

Question 13

what is optic nerve

Question 14

what is the fovea and periphery

Question 15

what is scotopic and photopic

Question 16

what are blood vessels

Question 17

what is a blind spot

Question 18

what is an optic disk

Question 19

describe adaptation

Question 20

how do we correct nearsightedness and farsightedness

Question 21

what are neurons and its structure

Question 22

what is an action potential

Question 23

what is EPSP and IPSP

Question 24

how do we record from neurons w an electrode

Question 25

how do excitation and inhibition counteract each other

Question 26

describe spontaneous activity

Question 27

what are ganglion cells

Question 28

what are receptive fields

Question 29

describe rf on skin