Week 2: Perception

Question 1

Why must Sensory Information be Interpreted?

Answer 1

1) Incomplete Information
2) Information Overload
3) Extract Important or Dangerous Information

Question 2

Vision

Answer 2

The only sense (out of 5 senses) to have an entire brain lobe dedicated to it (occipital lobe or cortex).

It is not a simple process of capturing images; it’s a complex construction built by the brain based on sensory input.

Question 3

Visual Cortex / Occipital Lobe

Answer 3

Region of the brain that shows the complexity of vision and reveals how it’s not simply a passive projection of the outside world into the brain.

Question 4

Retina

Answer 4

Located in the back of the eyes.

These are where all the rods and cones are.

Question 5

Rods and Cones

Answer 5

The light receptor cells that we need to see.

Question 6

Rods

Answer 6

They work when we have very little light available in the visual field.

They’re not sensitive to color information, and so vision in the dark is black and white.

Question 7

Cones

Answer 7

Are sensitive to colour information.

They only work in well-lit conditions and enable colour vision.

They are found only on the part of the retina labelled fovea in the figure right at the back of the eye in the middle.

Question 8

Fovea

Answer 8

Central part of the retina with the highest concentration of cones.

Question 9

Visual Field

Answer 9

The area we can see without moving our head.

The center is processed by both eyes (binocular vision), while the sides are processed by only one eye.

Question 10

Optic Nerve

Answer 10

Carries visual information from the retina to the brain.

Question 11

Optic Chiasm

Answer 11

Where the optic nerves cross, separating information from the left and right visual fields.

Question 12

Thalamus

Answer 12

A hub for sensory information entering the brain
relaying incoming input to relevant parts of the cortex for more detailed processing.

Question 13

Lateral Geniculate Nucleus (LGN)

Answer 13

Part of the thalamus specifically concerned with visual information.

Question 14

Primary Visual Cortex (V1)

Answer 14

Sometimes called Striate Cortex.

The initial processing area for visual information in the occipital lobe.

Question 15

Binocular Vision

Answer 15

Limited to the central part of the visual field.

Question 16

Colour Vision

Answer 16

Primarily based on information from the fovea.

Question 17

2 Principles of Vision

Answer 17

1. Hierarchical Processing: Vision starts with simple elements (dots, lines) and gradually builds up to complex objects and motion.
2. Modular Organization: Different parts of the visual cortex handle specific aspects of vision (e.g., color, motion).

Question 18

Key Areas of Vision

Answer 18

V1 (Primary Visual Cortex): Basic visual information (lines and edges). Damage leads to blindness.

V2 (Secondary Visual Cortex): Contour integration, Texture perception, Illusion perception, Color processing (with V4). Damage results in impaired texture perception.

V3: Form perception (shapes and objects), Depth perception (3D), Motion analysis (w V5). Damage results in impaired depth perception

V4: Handles color information. Damage results in color blindness.

V5: Processes motion. Damage causes motion blindness.

Question 19

Dorsal

Answer 19

Refers to locations nearer the top of the brain

Question 20

Ventral

Answer 20

Refers to locations nearer the bottom of the brain.

Question 21

Dorsal Stream (Where stream)

Answer 21

Runs from V1 to the parietal cortex.

Concerned with spatial information, location
judgments, and motion

Question 22

Spatial Information

Answer 22

Where things are in the world around you where they
are compared to you and where they are in relation to one another

Question 23

Ventral Stream (What stream)

Answer 23

Runs from V1 to the temporal cortex.

Concerns what the visual elements are, and is important in object recognition decisions.

Question 24

Visual Elements

Answer 24

Starts with the construction of simple forms, then shapes, and finally whole objects. This includes
some dedicated processing of category-specific information, for example, faces.

Question 25

Visual Agnosia

Answer 25

A disorder in which following damage to parts of the ventral stream, patients become unable to recognise objects or even when more severe and affecting areas nearer to primary visual cortex, simple shapes.

Question 26

Parietal Cortex

Answer 26

The primary attention area in the brain.

Question 27

Attention

Answer 27

Our ability to spatially represent the outside world is linked with this concept.

Question 28

3D Information

Answer 28

Only gained from the perifoveal part of the visual field.

Question 29

Saccades

Answer 29

Constant eye movements between successive fixations across the visual field. The images that we process, then, are integrated automatically and very cleverly by our brains.

Question 30

Successive Fixation

Answer 30

Looking at one point, then quickly moving to another and focusing there, and repeating this process.

Question 31

Change Blindness

Answer 31

our illusion of seeing the world around us in rich detail is not true,
and that we’re actually very inaccurate at perceiving things that are right in front of us.

Question 32

Blind Spot

Answer 32

This is where the optic nerve fibres take the visual input from the retina to the brain.

A fascinating example of how our brain fills in missing information to create a seamless visual experience.

Question 33

Visual Input

Answer 33

Contains overwhelming information, and so we’re flooded with sensory stimulation, and we need a mechanism to select parts of this image that’s important to us.

And this selection mechanism is attention.

Question 34

Visual Input

Answer 34

In addition to being insufficient and overwhelming at times, the visual input is often ambiguous, and
so interpretation by our visual system is needed for us to understand what’s in front of us.

Question 35

Percept

Answer 35

The mental representation of a stimulus.

It’s essentially what your brain constructs from sensory input.

Question 36

Context

Answer 36

Refers to the surrounding environment or circumstances that influence how we interpret sensory information.