Pattern recognition

Question 1

How does object and pattern recognition work?

Answer 1

• Both has very complex systems
• Pattern recognition is alot about “problem solving”
• Uses both bottom-up processes and top-down processes

Question 2

Perceptual organization

Answer 2

How we divide a visual scene into individual objects and organize seperate parts of what we see into something meanful
- A telephone looking like one

Question 3

Feature detection

Answer 3

How we can recognize visual stimulus as familiar pattern
- Where letters mean something
- Detect small features first, then put them into a “whole”

Question 4

Gestalt psychology

Answer 4

• Principles that describes the regularities according to which we grup visual input
• The whole part is different than the sum of its parts
  How we percieve objects

Question 5

Figure-ground principle

Answer 5

• One part figure and the other is a background
  Vase-two faces picture

Question 6

Closure principle

Answer 6

Filling the gaps in a line or something, to make sense of it

Question 7

Proximity principle

Answer 7

Whats near tend to be grouped together, in perception

Question 8

Similarity principle

Answer 8

Visually similar, same color or texture

Question 9

Good continuation principle

Answer 9

The dots or lines continues in a similar fashion
- Assuming smooth lines

Question 10

Common fate principle

Answer 10

Enteties that move together are perceptually grouped together
- Such as movement

Question 11

Simplicity principle

Answer 11

Elements that are parts of a pattern tends to get grouped together
- Similarity
- Continuity
- What patterns you see instantly when looking at a pattern
What belongs together?

Question 12

How can we recongnize a visual stimulus as a familiar pattern?

Answer 12

• Detection of simple features
  Different types of lines that form certain letters

Question 13

Pandemonium model

Answer 13

A very bottum-up processing
- Different types of demons
Mental mechanisms that process stimulus
- The demon that screams the most has the “accurate” feauture to what we are seeing

Question 14

What are keypoints from the pandemonium model?

Answer 14

• Parallel processes
  More than one process at a time trying to figure out the pattern
• Stimulus driven detection
• Problem solving approach

Question 15

Feature detectors

Answer 15

• Specialized cells for various visual features and patterns
• Neurological differences

Question 16

Is pattern recongnition purely bottom-up process?

Answer 16

• No, it doesnt explain everything
• Context matters
  Same looking symbol/letter can be a different letter in different words
• Prior knowledge, expectations

Question 17

Connectionist model - Pattern recognition

Answer 17

• For words
• Input units
  Responds to different features
• Hidden units
  Internal process, find connection between input units where positive activation leads to
• Output units
  What we perceive as words
• Top-down process
  Some spelling patterns more likely than others
  Expectations on what letter comes afterwards

Question 18

Repetition Blindness

Answer 18

Tendency to not percieve a pattern when its quickly repeated

Question 19

Misreading Effect

Answer 19

Tendency to read a word that is not there but should due to context.

Question 20

What does Muller-Lyer visual illusion arise from?

Answer 20

Culture differences
- People who has been brought up in areas where corners of building are often lacking feel like the two lines are similar in length
- Good continuation