An introduction to applied cognitive science
David Groome & Michael W. Eysenck
Chapter 1
An introduction to applied cognitive science
- Cognitive psychology:
• The study of the mental processes involved in acquiring and making use of the
knowledge and experience gained from our senses and those involved in
planning action.
- Main processes:
• Perception
• Learning
• Memory storage
• Retrieval
• Thinking
- Types of information:
• Visual
• Auditory
• Tactile
• Gustatory
• Information
• Symbolic language
- Applied cognitive psychology:
• How cognitive processes affect our behaviour and performance in real life
- Reasons for applied cognitive psychology
• Produce solutions to real problems
• Improve theoretical approaches
Article: Simon & Levin
Change blindness
- Change blindness:
• If the meaning of a scene remains, changes to attended objects can escape
detection
- Ability to detect retinal differences eliminated:
• Failure to detect substantial changes (photographs objects, real world
scenes)
, ➔ Retinally localizable information signaling change masked by eye
movement or flashed blank screen
- Change blindness:
• Lack of precise visual representation of world from one view to the next
➔ Memory for scenes often distorted
➔ Details aren’t retained from one instant to the next
➔ Richness of visual world is hard to represent all visual details
• Representations of centrally attended objects can be detailed, even if those
of peripheral objects aren’t
- Role of attention in detection of changes:
• Changes to objects that people consider to be the center of interest of a
scene require less alternations to be detected than changes to peripheral
objects
• Attention is helpful for change detection, but not sufficient
- Does it help when people are tested in the real world?
• Experiment 1 shows the people of the age of the experimenters noticed the
change more than those who were older. Presumably because the younger
ones consider them to be of the same social group (in-group), therefore put
more effort into remembering their features
• Experiment 2: only young people were approached, still only 4 out of 12
people noticed the switch
➔ When the experimenters look like an out-group, the chances of noticing
the change were reduced
➔ ‘sees it’s a construction worker -> doesn’t code individual features ->
forming a representation of the category
- Successful change detection:
• Effortful encoding of the features that distinguish the original from the
changed object
- General discussion
Chapter 2
Perception and attention
- Perception is something that just happens, that we’re not aware of
• First stage is process of perception: sensations that we collect through our
senses
-> how many senses we have can be classified in different ways
, • Focus on vision: our vision provides us with too much information to all be
processed
-> attention filters this information to a manageable level
• Memory and knowledge can influence our perception
-> if you know what something is likely going to be, you can prepare yourself for it
• What is left after the filtering of our attention + what we know = our perception
-> what we perceive may not be the same as what we sense
-> interaction works the same (if you know the place that something you’re
looking for will probably be -> you’ll focus on this place)
- Driving – A risky business
• Fatal accidents mostly involve pedestrians, particularly at night
• can the data, theory and practice of psychology provide any insights to help
reduce the likelihood of a driver running over a pedestrian at night?
- From the eye to the brain
• Purkinje shift:
-> change in the peak colour-sensitivity of the visual system as it alters from
photopic to scotopic vision
• would more light help with seeing pedestrians?
-> not necessarily, these cells do not respond to light per se, they respond to
contrast
-> Edges between objects and the background are usually defined by contrast. If
the contrast between an object and its background is low, it is difficult to ‘pick
out’ that object and recognise it
• Usually, the pedestrian is only a small part of the visual scene.
• Influence rest of visual field:
-> bright areas in the field of view lower drivers’ overall contrast sensitivity
• The higher the contrast of a pedestrian, the better chance they have of being seen
• A different solution to making a pedestrian more visible is to change the
characteristics of the pedestrian so that they are of a higher contrast
-> retroreflectors
- Gibsons ecological approach to perception
• perception is less about working out what something is, and more about working
out what to do with it
-> perception for action
• people aren’t just observing their environment, they’re interacting with it
-> our perceptual systems support this interaction by registering the visual field
• focus on information readily available in the visual scene
, -> little focus on knowledge
• Direct perception (bottom-up approach)
-> information straight from senses to perception
• Optic flow:
-> to the differential motion of the optic array with respect to the viewer.
-> If an individual moves forward the world, relative to them, moves past them.
• people can use the rate at which an object increases in size to gauge their speed
of approach.
-> drivers can use their this to control their braking
-> judgements in TTC vary (which shouldn’t happen, using only optic flow)
-> driver need to be aware of the need to brake in the first place
-> rate of braking, but not when to start braking
- Brake of Break – a failure of direct perception
• even vehicles with a high contrast stimulus get hit by drivers because they ‘didn’t
see it’
-> ‘looked but failed to see’
-> previous experience (top-down processing) plays a role, as many of the
accidents involved experienced drivers on well-known roads, which shows their
knowledge also played a role
- A constructivist approach to perception
• based on the notion that it is necessary for us to ‘construct’ our perception of
what we see from incomplete sensory (bottom-up) information
-> everything we need for perception is there in the visual stimulus.
-> we use what we already know to fill in the gaps
-> acting as ‘scientists’: generating hypotheses about what we may be seeing and
testing it against sensory information
• size consistency:
-> In the Ponzo illusion the two lines are actually the same length, but one
appears to be further away and so is scaled up by our visual system, giving the
impression that it is longer.
• When driving, and seeing a car in the same orientation as a moving car, people
rely on what they know and assume they’re seeing a moving car
- two approaches, two streams
• Dorsal stream
-> constructivist
-> recognition and identification of what is in the visual field
-> motion
-> short term storage
David Groome & Michael W. Eysenck
Chapter 1
An introduction to applied cognitive science
- Cognitive psychology:
• The study of the mental processes involved in acquiring and making use of the
knowledge and experience gained from our senses and those involved in
planning action.
- Main processes:
• Perception
• Learning
• Memory storage
• Retrieval
• Thinking
- Types of information:
• Visual
• Auditory
• Tactile
• Gustatory
• Information
• Symbolic language
- Applied cognitive psychology:
• How cognitive processes affect our behaviour and performance in real life
- Reasons for applied cognitive psychology
• Produce solutions to real problems
• Improve theoretical approaches
Article: Simon & Levin
Change blindness
- Change blindness:
• If the meaning of a scene remains, changes to attended objects can escape
detection
- Ability to detect retinal differences eliminated:
• Failure to detect substantial changes (photographs objects, real world
scenes)
, ➔ Retinally localizable information signaling change masked by eye
movement or flashed blank screen
- Change blindness:
• Lack of precise visual representation of world from one view to the next
➔ Memory for scenes often distorted
➔ Details aren’t retained from one instant to the next
➔ Richness of visual world is hard to represent all visual details
• Representations of centrally attended objects can be detailed, even if those
of peripheral objects aren’t
- Role of attention in detection of changes:
• Changes to objects that people consider to be the center of interest of a
scene require less alternations to be detected than changes to peripheral
objects
• Attention is helpful for change detection, but not sufficient
- Does it help when people are tested in the real world?
• Experiment 1 shows the people of the age of the experimenters noticed the
change more than those who were older. Presumably because the younger
ones consider them to be of the same social group (in-group), therefore put
more effort into remembering their features
• Experiment 2: only young people were approached, still only 4 out of 12
people noticed the switch
➔ When the experimenters look like an out-group, the chances of noticing
the change were reduced
➔ ‘sees it’s a construction worker -> doesn’t code individual features ->
forming a representation of the category
- Successful change detection:
• Effortful encoding of the features that distinguish the original from the
changed object
- General discussion
Chapter 2
Perception and attention
- Perception is something that just happens, that we’re not aware of
• First stage is process of perception: sensations that we collect through our
senses
-> how many senses we have can be classified in different ways
, • Focus on vision: our vision provides us with too much information to all be
processed
-> attention filters this information to a manageable level
• Memory and knowledge can influence our perception
-> if you know what something is likely going to be, you can prepare yourself for it
• What is left after the filtering of our attention + what we know = our perception
-> what we perceive may not be the same as what we sense
-> interaction works the same (if you know the place that something you’re
looking for will probably be -> you’ll focus on this place)
- Driving – A risky business
• Fatal accidents mostly involve pedestrians, particularly at night
• can the data, theory and practice of psychology provide any insights to help
reduce the likelihood of a driver running over a pedestrian at night?
- From the eye to the brain
• Purkinje shift:
-> change in the peak colour-sensitivity of the visual system as it alters from
photopic to scotopic vision
• would more light help with seeing pedestrians?
-> not necessarily, these cells do not respond to light per se, they respond to
contrast
-> Edges between objects and the background are usually defined by contrast. If
the contrast between an object and its background is low, it is difficult to ‘pick
out’ that object and recognise it
• Usually, the pedestrian is only a small part of the visual scene.
• Influence rest of visual field:
-> bright areas in the field of view lower drivers’ overall contrast sensitivity
• The higher the contrast of a pedestrian, the better chance they have of being seen
• A different solution to making a pedestrian more visible is to change the
characteristics of the pedestrian so that they are of a higher contrast
-> retroreflectors
- Gibsons ecological approach to perception
• perception is less about working out what something is, and more about working
out what to do with it
-> perception for action
• people aren’t just observing their environment, they’re interacting with it
-> our perceptual systems support this interaction by registering the visual field
• focus on information readily available in the visual scene
, -> little focus on knowledge
• Direct perception (bottom-up approach)
-> information straight from senses to perception
• Optic flow:
-> to the differential motion of the optic array with respect to the viewer.
-> If an individual moves forward the world, relative to them, moves past them.
• people can use the rate at which an object increases in size to gauge their speed
of approach.
-> drivers can use their this to control their braking
-> judgements in TTC vary (which shouldn’t happen, using only optic flow)
-> driver need to be aware of the need to brake in the first place
-> rate of braking, but not when to start braking
- Brake of Break – a failure of direct perception
• even vehicles with a high contrast stimulus get hit by drivers because they ‘didn’t
see it’
-> ‘looked but failed to see’
-> previous experience (top-down processing) plays a role, as many of the
accidents involved experienced drivers on well-known roads, which shows their
knowledge also played a role
- A constructivist approach to perception
• based on the notion that it is necessary for us to ‘construct’ our perception of
what we see from incomplete sensory (bottom-up) information
-> everything we need for perception is there in the visual stimulus.
-> we use what we already know to fill in the gaps
-> acting as ‘scientists’: generating hypotheses about what we may be seeing and
testing it against sensory information
• size consistency:
-> In the Ponzo illusion the two lines are actually the same length, but one
appears to be further away and so is scaled up by our visual system, giving the
impression that it is longer.
• When driving, and seeing a car in the same orientation as a moving car, people
rely on what they know and assume they’re seeing a moving car
- two approaches, two streams
• Dorsal stream
-> constructivist
-> recognition and identification of what is in the visual field
-> motion
-> short term storage
