Coordinator Questions
Problem 5 1. Although all visual agnosias constitute problems in visual
Case 1: perception, some forms of agnosia are more perceptual in
1. How do we organize/group different elements? nature than others. That is, patients with some forms of
2. How do we distinguish between background and visual agnosia have severe problems forming a visual
foreground? representation of the object whereas patients with other
3. How does pattern recognition work? forms of visual agnosia don’t. elaborate on this.
Case 2: 2. Treisman and Gelade investigated visual search. They
1. What is the geon? distinguished between two types of visual search. What
2. How do we fill gaps to create recognizable objects? How are those types? How do these differ? What attentional
long does it take? mechanisms play a role in these types of search?
Tips: make sure to read all theories about object recognition 3. Discuss the recognition-by-components theory
Case 3: (Biederman). What are important properties of geons?
1. What are these patients suffer from? 4. Problems in visual perception such as visual agnosia,
2. What is prosopagnosia? prosopagnosia and alexia rarely occur in isolation. That is,
3. How does the brain process faces and objects? patients typically have problems recognizing different
4. Are there different regions involved for faces and/or kinds of stimuli (not just one type). What combinations of
objects? deficits are common; which are less common? How can
this be explained?
Source: Goldstein, 6th ed, Chapter 5, pp 145-184 5. Name some important Gestalt principles/laws.
The Gestalt Approach to Perceptual Organization: How Elements are Grouped
The beginnings of Gestalt Psychology
Structuralism: behaviour is created by adding elementary elements. When applied to
perception, structuralism stated that perceptions were created by combining elements
called sensations.
Apparent movement: An illusion that occurs when two stimuli that are in slightly different
positions are flashed, with the correct timing, one after the other, movement is perceived
between the two. It is called apparent movement because there is no actual movement in
the display, just two stationary stimuli flashing on and off.
It is difficult to explain a perception that is present one moment
and gone the next in terms of sensations, especially since the
stimulus on the page and the image it creates on your retina are
exactly the same when the contours are visible and when they
are not.
examples such as these led the Gestalt psychologists to state
one of the basic principles of Gestalt psychology: The whole is
different than the sum of its parts.
Perceptual organization: how small elements become grouped into larger objects.
, The Gestalt Laws of Perceptual Organization
A series of rules that specify how we organize small parts into a whole. Six Gestalt laws.
Pragnanz: “good figure” central law of Gestalt psychology
- The law of Pragnanz/ the law of good figure/the law of simplicity states that every
stimulus pattern is seen in such a way that the resulting structure is as simple as
possible. E.g. Olympic symbol, five circles not 9 complicated shapes.
Similarity:
- The law of similarity: similar things appear to be grouped together. This law causes
the circles to be grouped with other circles and the squares to be grouped with other
squares.
- Grouping can also occur because of similarity of lightness, hue, size, or orientation.
- Grouping can also occur for auditory stimuli. E.g. notes grouped melody.
Good continuation:
- The law of good continuation: points that, when connected, result in straight or
smoothly curving lines are seen as belonging together, and the lines tend to be seen
in such a way as to follow the smoothest path. E.g. cable example
Proximity or nearness:
- Law of proximity or nearness: things that are near to each other appear to be
grouped together.
Common fate:
- The law of common fate: things that are moving in the same direction appear to be
grouped together. E.g. dancers.
Meaningfulness or Familiarity
- Law of familiarity: things are more likely to form groups if the groups appear familiar
or meaningful. E.g. the forest has eye picture with hidden faces.
The Gestalt “Laws” are Really Heuristics
- Most perceptual psychologists call them Gestalt “principle” instead of Gestalt laws
because the rules proposed by the Gestalt psychologists don’t make strong enough
predictions to qualify as laws.
Problem 5 1. Although all visual agnosias constitute problems in visual
Case 1: perception, some forms of agnosia are more perceptual in
1. How do we organize/group different elements? nature than others. That is, patients with some forms of
2. How do we distinguish between background and visual agnosia have severe problems forming a visual
foreground? representation of the object whereas patients with other
3. How does pattern recognition work? forms of visual agnosia don’t. elaborate on this.
Case 2: 2. Treisman and Gelade investigated visual search. They
1. What is the geon? distinguished between two types of visual search. What
2. How do we fill gaps to create recognizable objects? How are those types? How do these differ? What attentional
long does it take? mechanisms play a role in these types of search?
Tips: make sure to read all theories about object recognition 3. Discuss the recognition-by-components theory
Case 3: (Biederman). What are important properties of geons?
1. What are these patients suffer from? 4. Problems in visual perception such as visual agnosia,
2. What is prosopagnosia? prosopagnosia and alexia rarely occur in isolation. That is,
3. How does the brain process faces and objects? patients typically have problems recognizing different
4. Are there different regions involved for faces and/or kinds of stimuli (not just one type). What combinations of
objects? deficits are common; which are less common? How can
this be explained?
Source: Goldstein, 6th ed, Chapter 5, pp 145-184 5. Name some important Gestalt principles/laws.
The Gestalt Approach to Perceptual Organization: How Elements are Grouped
The beginnings of Gestalt Psychology
Structuralism: behaviour is created by adding elementary elements. When applied to
perception, structuralism stated that perceptions were created by combining elements
called sensations.
Apparent movement: An illusion that occurs when two stimuli that are in slightly different
positions are flashed, with the correct timing, one after the other, movement is perceived
between the two. It is called apparent movement because there is no actual movement in
the display, just two stationary stimuli flashing on and off.
It is difficult to explain a perception that is present one moment
and gone the next in terms of sensations, especially since the
stimulus on the page and the image it creates on your retina are
exactly the same when the contours are visible and when they
are not.
examples such as these led the Gestalt psychologists to state
one of the basic principles of Gestalt psychology: The whole is
different than the sum of its parts.
Perceptual organization: how small elements become grouped into larger objects.
, The Gestalt Laws of Perceptual Organization
A series of rules that specify how we organize small parts into a whole. Six Gestalt laws.
Pragnanz: “good figure” central law of Gestalt psychology
- The law of Pragnanz/ the law of good figure/the law of simplicity states that every
stimulus pattern is seen in such a way that the resulting structure is as simple as
possible. E.g. Olympic symbol, five circles not 9 complicated shapes.
Similarity:
- The law of similarity: similar things appear to be grouped together. This law causes
the circles to be grouped with other circles and the squares to be grouped with other
squares.
- Grouping can also occur because of similarity of lightness, hue, size, or orientation.
- Grouping can also occur for auditory stimuli. E.g. notes grouped melody.
Good continuation:
- The law of good continuation: points that, when connected, result in straight or
smoothly curving lines are seen as belonging together, and the lines tend to be seen
in such a way as to follow the smoothest path. E.g. cable example
Proximity or nearness:
- Law of proximity or nearness: things that are near to each other appear to be
grouped together.
Common fate:
- The law of common fate: things that are moving in the same direction appear to be
grouped together. E.g. dancers.
Meaningfulness or Familiarity
- Law of familiarity: things are more likely to form groups if the groups appear familiar
or meaningful. E.g. the forest has eye picture with hidden faces.
The Gestalt “Laws” are Really Heuristics
- Most perceptual psychologists call them Gestalt “principle” instead of Gestalt laws
because the rules proposed by the Gestalt psychologists don’t make strong enough
predictions to qualify as laws.
