Perception

Question 1

Perception

Answer 1

How external world gets represented in our brain/mind so that we can understand and act upon what’s going on around us

Question 2

Apperceptive agnosia
Associative agnosia

Answer 2

Unable to name/match/discriminate visually presented objects
- Failure to combine visual info to complete percept (deficits in copying)

Unable to associate visual pattern w/ meaning
- Can combine features into a whole so can copy

Question 3

3 steps to visual perception

Answer 3

Input/sensation

Basic visual components assembled

Meaning linked to visual input

Question 4

Senses that measure properties of our own body (interoception):
Propioception
Nociception
Equilibrioception

Answer 4

Location of limbs in space

Pain due to internal bodily damage

Sense of balance

Question 5

Experience error
Inverse projection problem

Answer 5

False assumption that structure of world is directly given from our senses

Perception only uses hints to retrieve 3D object; We only see 2D projection of it

Question 6

Fixation-saccade cycles

Answer 6

Vision is combo of
- Smooth pursuit movement (when eyes following object; info processed)
- Saccade (eyes shift between scenes; input not processed)

Perception fills in the gaps

Question 7

Bottom-up processing
Top-down processing

Answer 7

Data driven
Recognize patterns by analyzing sensory input step by step

Conceptually driven
Perception influenced by prior knowledge, memories, exp

Question 8

Template theory

Answer 8

We have mental stencil for an array of diff patterns
- Important for computers perceiving letters

Not good for humans bcuz everyone has diff writing

Question 9

Feature matching
Pandemonium theory
Feature detector neurons

Answer 9

We have a system for analyzing each distinct feature of a visual item

Break down into distinct visual features and out them back together
- Whichever demon is shouting loudest is correct
- Serial (between demon types) and parallel (each demon working at same time) processes
**Insufficient bcuz unknown how pieces are put back together

Found in primary visual cortex; responds to specific input/stimulus

Question 10

Prosopagnosia
Semantic agnosia
Fusiform face area (FFA)

Answer 10

Difficulty recognizing faces

Difficulty recognizing objects except for faces

Region in inferior temporal cortex that shows greatest activity when performing face-specific tasks

Question 11

Visual streams:
Ventral stream
Dorsal stream

Answer 11

Terminates temporal lobe
- Concerned w/ processing “what”

Terminates parietal lobe
- Concerned w/ processing “where”

Division between them is of perception vs action

Question 12

Biderman’s Recognition by Components (Geon theory)

Answer 12

3D shapes called geons
To identify object, you match to geon

Recognition is impaired when objects viewed from non-canonical viewpoints (unusual angles)

Humans appear to have viewer centred bias
Object recognition faster from familiar viewpoints
Cortical neurons show viewpoint specificity

Question 13

Scene schemas
(Top-down processing)

Answer 13

Used to help identify objects in familiar enviros

Question 14

Gestalt psychology

Answer 14

How perception gets organized into meaningful units
- Whole is different than sum of its parts

Question 15

Gestalt laws for grouping

Answer 15

Law of proximity (Close together, grouped together)
Law of similarity (Similar, grouped together)
Law of common region (Enclosed within same region, grouped together)

Experience
- Things associated together in prior viewings will be grouped together in future

Question 16

Direct perception (Gibson)
Ambient optic array
Optic flow

Answer 16

Enviro contains all info needed for perception
- Uses action

Structure imposed in light by enviro, contains info needed

Motion/flow in optic array gives info:
- Flow = Observer is in motion
- Direction of flow = Direction observer is moving in
- Flow coming out of point = Object moving closer
- Flow moving toward point = Perceiver moving away

Question 17

Objects’ affordances

Answer 17

Goal of perception is to provide perceiver with this info
- Tells us what you can do with object
- Depends on object and observer

Question 18

Modern researchers’ belief on perception
(Related to Gibson’s view)

Answer 18

Both actions and representations involved in perception
- Action influences how we perceive the world

Question 19

Ideomotor apraxia

Answer 19

Can’t act out actions w/ objects (how to us)
- Damage to parietal lobe (“where” pathway)

Question 20

Motor plan
Mirror neurons

Answer 20

Voluntary movement plans goal of action and how it’ll be accomplished

Involved in planning
- Responds equally when performing and viewing an action

Question 21

Tanaka and Farah
(Face processing)

Answer 21

Found that it’s easier to recognize parts of a house than parts of faces

Question 22

Face inversion effect

Answer 22

We’re faster and more accurate at recognizing upright faces compared to inverted faces

Question 23

Diamond and Carey dog identification study

Answer 23

Dog experts perceived dogs similarly to how we perceive faces
(Better upright)

Question 24

Phonemic restoration effect

Answer 24

Missing sounds are “filled in” by brain based on knowledge of language

Question 25

Figure-ground assignment

Answer 25

The determination of which side of a boundary contains the shape vs background

Question 26

General recognition

Answer 26

Ability for a computer to classify a broad class of diff objects

Question 27

Scene schema

Answer 27

Learned representation of which objects tend to appear in specific kinds of scenes

Question 28

Convolutional neural networks (CNNs)

Answer 28

Learns features that can appear in diff locations in an image
- Useful for computers to recognize image as being part if category

Kernels or filters: Array of numbers used to detect presence of image features
- Produces feature map (shows how much of the feature is present across diff locations of the image)