Chapter 4, pt.2

Question 1

What part of the brain is responsible for perceiving shape?

Answer 1

Area V1 in the occipital lobe (primary visual cortex); it detects edges and orientations through feature detectors – neurons specialized for specific features like lines and edges.

Question 2

What are feature detectors?

Answer 2

Specialized neurons in V1 that respond to specific visual features such as edges, lines, and orientations.

Question 3

What are the two main visual streams and their functions?

Answer 3

Dorsal (“where”) stream → Parietal lobe: location, movement, spatial relations.

Ventral (“what”) stream → Temporal lobe: shape and identity (recognition of objects/faces).

Question 4

What happens if the dorsal stream is damaged?

Answer 4

Difficulty reaching and grasping objects, but normal object identification.

Question 4

What happens if the ventral stream is damaged?

Answer 4

Visual agnosia – inability to recognize objects by sight, though touch recognition remains normal.

Question 5

What is parallel processing in vision?

Answer 5

The brain’s ability to analyze multiple features (colour, shape, motion, etc.) at once and integrate them into a unified perception.

Question 6

What is a binding problem?

Answer 6

When parallel processing fails to integrate features correctly, leading to miscombined or “free-floating” features.

Question 7

What is an illusory conjunction?

Answer 7

A perceptual mistake where features from different objects are incorrectly combined (e.g., mixing colour and shape).

Question 8

According to feature-integration theory, what is the role of attention?

Answer 8

Focused attention is required to bind individual features into a coherent object perception.

Question 9

How do humans recognize patterns?

Answer 9

• modular view
• Distributed representation of object categories
• Single neurons (concept)

Question 10

What is the modular view of object recognition?

Answer 10

Specific brain areas (modules) are specialized for detecting faces, houses, bodies, etc.

Question 11

What is the distributed representation view?

Answer 11

Objects are recognized through patterns of activity across multiple brain regions.

Question 12

What are “concept neurons”?

Answer 12

Neurons that respond to specific objects or concepts across different views or modalities (e.g., a specific person’s image or name).

Question 13

What is perceptual constancy?

Answer 13

The tendency to perceive objects as unchanging despite variations in sensory input (e.g., lighting, distance).

Question 14

what is perceptual organization?

Answer 14

Grouping and segregating features to form coherent, meaningful objects.

Question 15

Name the Gestalt principles of perceptual grouping.

Answer 15

Simplicity, Closure, Continuity, Similarity, Proximity, Common Fate.

Question 16

Explain Gestalt – Simplicity.

Answer 16

We perceive the simplest possible interpretation of a complex image.

Question 17

Explain Gestalt – Closure.

Answer 17

We fill in missing elements to see complete figures despite gaps.

Question 18

Explain Gestalt – Continuity.

Answer 18

We tend to follow smooth continuous lines or paths.

Question 19

Explain Gestalt – Similarity.

Answer 19

Elements sharing attributes (colour, shape, size) are grouped together.

Question 20

Explain Gestalt – Proximity.

Answer 20

Objects close to each other are perceived as part of the same group.

Question 21

Explain Gestalt – Common Fate.

Answer 21

Elements moving in the same direction are perceived as one object.

Question 22

What is figure-ground separation?

Answer 22

Distinguishing an object (figure) from its background (ground); smaller regions are often perceived as figures. Example: Rubin’s Vase.

Question 23

What are monocular depth cues?

Answer 23

Depth cues that work with one eye only, like familiar size, linear perspective, texture gradient, interposition, and relative height.

Question 23

Define familiar size.

Answer 23

Using knowledge of an object’s usual size to estimate distance.

Question 24

Define linear perspective.

Answer 24

Parallel lines appear to converge in the distance (e.g., railroad tracks).

Question 25

Define texture gradient.

Answer 25

Textures look more detailed when close and finer when far away.

Question 26

Define interposition.

Answer 26

When one object overlaps another, the overlapping object is seen as closer.

Question 27

Define relative height.

Answer 27

Objects lower in the visual field are perceived as closer.

Question 28

What is binocular disparity?

Answer 28

Difference between the retinal images in each eye that the brain uses to calculate depth; greater disparity = closer object.

Question 29

What is required for motion perception?

Answer 29

Encoding of both space and time, considering eye and body movements.

Question 30

What is the waterfall illusion?

Answer 30

After viewing movement in one direction, a stationary object appears to move the opposite way (due to opponent process adaptation).

Question 31

What is biological motion perception?

Answer 31

The ability to detect movement patterns of living beings (even with minimal visual cues, like point-light displays).

Question 32

Which brain areas process motion?

Answer 32

MT (temporal lobe, dorsal stream) for object motion; STS for biological motion; TPJ for social cognition.

Question 33

Define blindness.

Answer 33

Severe vision loss not correctable by lenses or surgery; exists on a spectrum—most retain some vision.

Question 34

What is selective attention?

Answer 34

Focusing on specific stimuli to analyze them better since perceptual resources are limited.

Question 35

What is inattentional blindness?

Answer 35

Failure to notice an unexpected object when attention is focused elsewhere (e.g., gorilla experiment).

Question 36

What is change blindness?

Answer 36

Failure to detect visual changes in a scene (e.g., Simons & Levin 1998 door study – only 7/15 noticed the switch).

Question 37

What are the three parts of the ear and their functions?

Answer 37

Outer ear: Collects sound waves. Middle ear: Transmits vibrations via ossicles (malleus, incus, stapes). Inner ear: Converts vibrations into neural impulses (transduction).

Question 38

What are the ossicles?

Answer 38

The three tiny bones in the middle ear – malleus (hammer), incus (anvil), stapes (stirrup).