PSYCH 104 Midterm 2 (The eyes and conciousness)

Question 1

Visible light: What wavelengths can we see?

Answer 1

Visible light:
- Electromagnetic radiation between 400 and 700 nanometers

Question 2

Hue:

Answer 2

Hue:
- The colour of light

Question 3

The cornea

Answer 3

• The cornea
  ○ Part of the eye containing transparent cells that focus light on the retina
  § Myopia (nearsightedness)
  □ The cornea is too long causing the focus of light to be Infront of the retina
  § Hyperopia (farsightedness)
  □ Cornea is too flat causing the focus of light to occur behind the retina

Question 4

The lens

Answer 4

• The lens
  ○ Part of the eye that changes curvature to keep images in focus
  ○ Contains transparent cells
  ○ Accommodation:
  § Changing the shape of the lens to focus on objects near or far

Question 5

The retina

Answer 5

• The retina
  Membrane at the back of the eye responsible for converging light into neural activity

Question 6

Rods

Answer 6

○ Rods
§ Photoreceptor cells in the retina allowing us to see in low levels of light
□ Dark adaptation: time in dark before rods regain maximum light sensitivity

Question 7

Cones

Answer 7

○ Cones
§ Photoreceptor cells in the retina allowing us to see in colour
§ More rods than cones

Question 8

Photopigments

Answer 8

○ Photopigments
§ Protein molecules within the rods and cones whose chemical reactions when absorbing light result in nerve impulses being generated

Question 9

Optic nerve

Answer 9

○ Optic nerve
§ Nerve (technically a bundle of ganglion cells) that travels from the retina to the brain

Question 10

Peripheral vision and nighttime

Answer 10

Peripheral vision and nighttime
- We have more rods that align with our peripheral vision
- Therefore we can see in the dark better with our peripheral vision than our central eye

Question 11

The eyeballs -> to the brain (what happens?)

Answer 11

The eyeballs -> to the brain
- On its way to the brain the sensory nerves cross over from right to left and left to right

Question 12

The blind spot

Answer 12

The blind spot
- Part of the visual field we cant see because of an absence of rods and cones

Question 13

Hubel and Wiesel (What did they do?)

Answer 13

○ Hubel and Wiesel
§ Records electrical activity of V1 area of visual cortex in cats
§ Discovered feature detector cells:
□ Cells that detect lines and edges
At later levels of visual processing (like V2) cells begin to detect more complex shapes and movements

Question 14

The principles of gestalt psychology (What are they?)

Answer 14

• The principles of gestalt psychology
  ○ A Germán school of psychology that emphasizes the natural organization of perceptual elements into wholes, or patterns
  ○ “gestalt” = “whole”
  ○ Psychology should be focused on how the “whole” is created from its basic parts
  ○ Main figures in perception
  § Max Wertheheimer
  § Wolfgang Kohler
  § Kurt Koffka

Question 15

The principles of gestalt psychology
○ Proximity

Answer 15

• The principles of gestalt psychology
  ○ Proximity:
  § Objects physically close to each other tend to be precieved as unidentified wholes

Question 16

The principles of gestalt psychology
○ Similarity

Answer 16

• The principles of gestalt psychology
  ○ Similarity:
  Similar objects will be seen as being grouped together or related

Question 17

The principles of gestalt psychology
- Continuity

Answer 17

• Continuity:
  ○ We precieve lines as continuous movement while discounting abrupt changes
  Also called “good continuation”

Question 18

The principles of gestalt psychology
- Closure

Answer 18

• Closure:
  ○ The tendancy to view incomplete figures or forms as complete objects

Question 19

The principles of gestalt psychology -
Symmetry

Answer 19

• Symmetry:
  ○ Symmetrically arranged objects are perceived as wholes

Question 20

The principles of gestalt psychology -
Figure-ground segregation

Answer 20

• Figure-ground segregation
  ○ The tendancy to separate elements of a image into a foreground (figure) and its background (ground)

Question 21

• Trichromatic theory:

Answer 21

• Trichromatic theory:
  ○ Idea that colour vision is based on our sensitivity to the three primary colours
  ○ Fits with later findings that three types of cone cells are present that respond maximally at different wavelengths
  § Short
  § Medium
  § Long
  ○ Relies on additive colour mixing
  ○ Cant account for afterimages

Question 22

Opponent process theory

Answer 22

• Opponent process theory:
  ○ Theory that we perceive colours in terms of three pairs of opponent colours
  § Red or green
  § Blue or black
  Black or white

Question 23

Dual-process theory

Answer 23

• Dual-process theory:
  ○ The modern colour version theory that posits that cones are sensitive to red, green, and blue as well as opponent processes at the level of ganglion cells

Question 24

Colour blindness

Answer 24

Colour blindness
- Inability to see some or all colours
- Usually due to genetic abnormalities that cause the absense/reduction in a specific cone type
○ Monochromats - only have one type of cone (very rare however)
○ Dichromats - have two types of cone
- Brain damage to cortical areas responsible for vision can also produce colour blindness

Question 25

- Depth perception

Answer 25

- Depth perception ○ The ability to judge distance and three dimensional relations § Monocular cues: □ Stimuli that enable us to judge depth using only one eye § Binocular cues: □ Stimuli that enable us to judge depth using both eyes

Question 26

Monocular cues - Relative size:

Answer 26

Monocular cues - Relative size: ○ All things being equal, more distant objects look smaller than closer objects

Question 27

Monocular cues - Texture gradient

Answer 27

- Texture gradient ○ The texture of objects becomes less apparent as they are farther away

Question 28

Monocular cues - Interposition

Answer 28

- Interposition ○ Close objects block the view of distant objects

Question 29

Monocular cues - Linear perspective

Answer 29

- Linear perspective ○ The outlines of objects converge as distance increases

Question 30

Monocular cues - Height in plane

Answer 30

- Height in plane ○ Here distant objects tend to appear higher and nearer objects appear lower

Question 31

Monocular cues - Light and shadow

Answer 31

- Light and shadow ○ The casting of shadows vives objects a 3-D form

Question 32

Monocular cues - Motion parallax

Answer 32

- Motion parallax ○ When objects loving across a field of view appear to move more the closer they are to an observer

Question 33

Binocular cues - Binocular disparity

Answer 33

Binocular cues - Binocular disparity ○ Depth information is obtained by comparing the difference in image location of the left and right eyes

Question 34

Binocular cues - Binocular convergence

Answer 34

- Binocular convergence ○ The degree to which your eyes converge inward gives provides information to estimate distance

Question 35

Blindness (vision loss)

Answer 35

Blindness (vision loss) - The inability to see due to problems with the eye and its related structures - Vision is less than or equal to 20/200 (20/20 is considered normal vision) - Rely more on other senses (touch, hearing, etc.) - Visual cortex's function changes due to neural plasticity

Question 36

Motion blindness (Cerebral Akinetopsia)

Answer 36

- Motion blindness (Cerebral Akinetopsia) ○ Neurological disorder in which a person is not able to perceive motion ○ Often caused by § Brain damage § Alzheimer's disease

Question 37

- Visual agnosia

Answer 37

- Visual agnosia ○ A failiure to recognize visually presented objects § Not due to impairments in memory or intelligence ○ Often due to damage to peripheral regions of occipital cortex near the parietal and temporal lobes

Question 38

- Visual agnosia (What are the 4 types?)

Answer 38

○ Different types § Prosopagnosia: failiure to recognize faces § Anosognosia: cant recognize illness § Finger agnosia: cant recognize fingers § Topographical disorientation: cant recognize places

Question 39

- Blindsight

Answer 39

- Blindsight ○ The ability of individuals with blindness to detect and respond to visual stimuli despite lacking awareness of having seen anything ○ Often the result of damage to V1 area of visual cortex

Question 40

Conciousness (What is it?)

Answer 40

- Conciousness: ○ The moment to moment subjective experience of the world, bodies and mental sensations § Subjective § Dynamic § Self-reflective ○ Interdisciplinary: § Physics, philosophy, psychology, neuroscience, computer sciences ○ How is it measured? § Self-reports § Physiological measures § Behavioral measures

Question 41

Cognitive psychology - The analogy

Answer 41

Cognitive psychology - The analogy ○ Humans are "information processors" the "mind" is the computers software and the brain is the computers hardware § Caveat: this is an oversimplification and not all cognitive psychologists agree with this interpretation

Question 42

- Controlled (effortful) processing:

Answer 42

- Controlled (effortful) processing: ○ Mental processing that requires some degree of volitional control and attentiveness § Voluntary use § Slow but flexible

Question 43

- Automatic processing:

Answer 43

- Automatic processing: ○ Mental activities that occur automatically and require no or minimal conscious control or awareness § Minimal conscious processing § Fast but static

Question 44

Divided attention:

Answer 44

Divided attention: - The ability to perform more than one activity at the same time ○ Difficult if tasks require similar cognitive resources § Example: like listening to music and studying for an exam