Visual perception (Part 1)

Question 1

What are the 2 aspects that help us experience vision?

Answer 1

1. Visual sensation
2. Visual perception

Question 2

Define visual sensation

Answer 2

The process of the eye receiving and responding to light

Question 3

Define visual perception

Answer 3

Interpreting the information

Question 4

What are the 5 stages of perception (in order)?

Answer 4

1. Reception
2. Transduction
3. Transmission
4. Selection
5. Organization/ interpretation

Question 5

Explain the process of reception

Answer 5

Light is captured by sensory receptors in the eye

Question 6

In order, state the 7 locations of reception

Answer 6

1. Cornea
2. Aqueous humor
3. Pupil
4. Lens
5. Vitreous humor
6. Retina
7. Optic nerve

Question 7

What does the frequency of light waves determine?

Answer 7

Colour

Question 8

What does a high light wave amplitude mean?

Answer 8

Brighter colours

Question 9

What are photoreceptors? Where are they located?

Answer 9

Light sensitive cells (rods and cones) located in the retina

Question 10

What is the different between Rods and Cones?

Answer 10

Rods: don’t detect colour, cylinder shape, peripheral vision, night vision
Cones: Shaped like cones, colour vision

Question 11

Explain the process of transduction

Answer 11

The conversion of electromagnetic energy to electrochemical (light to action potential)

Question 12

What is a receptor field?

Answer 12

Small groups of photoreceptors influenced by light to produce neural impulses

Question 13

What is visual field?

Answer 13

Comprised of many receptor fields

Question 14

Explain the process of transmission

Answer 14

Sending info from the retina to the primary visual cortex, via the optic nerve

Question 15

What side of the visual field does the right primary visual cortex

Answer 15

Left

Question 16

What is the optic chiasm

Answer 16

The cross over point between left and right

Question 17

Explain the process of selection

Answer 17

The process of differentiating the various components that makeup visual images

Question 18

What are feature detection neurons?

Answer 18

Detect attributes such as shape, size, orientation and motion

Question 19

What experimenters gained evidence for the feature detection neuron function? What was their experiment?

Answer 19

Hubel and Wiesel 1979

Examined neuron within the visual cortex of cats under anesthesia to see how they responded to visual attributes

Question 20

What was Hubel and Wiesel (1979) key findings?

Answer 20

• Found that detector neurons are organized systematically
• Primary visual cortex is developed directly after birth

Question 21

Explain the process of interpretation

Answer 21

Interpretation of visual stimulus is dependent on DEPTH CUES, VISUAL CONSISTENCIES, PERCEPTUAL SET, CULTURAL CONTEXT

Question 22

What kind of influence is ‘refractory errors’?
How is it caused?

Answer 22

Biological

Abnormalities in the cornea

Question 23

What are the 2 main types of refractory errors? Explain them.

Answer 23

1. Myopia (short-sidedness - can see close): light is focused on the front of the retina
2. Hyperopia (long-sidedness - can see far): light is unfocussed when it hits the retina

Question 24

What are 4 main types of age-related visual issues? describe them

Answer 24

1. Age-related Macular Degeneration (MD)
2. Presbyopia: the lens is too loose
3. Cataracts: Opacities that cause blur or glare
4. Glaucoma: Damaged optic nerve = blind spots

Question 25

TRUE OR FALSE: Genetics can influence visual perception

Answer 25

TRUE