Waarnemen en bewegen HC 7: taking action
- Chapter considering the ways in which perceptual processes such as these are involved in
being physically active in the world
- How perception and action interact
- We need to consider action to understand perception
- Ecological validity: an ecologically valid experiment matches its stimuli, conditions, and
procedures to those present in the natural world (Gibson)
- Gibson’s ecological approach to perception: to determine how movement creates perceptual
information that both guides further movement and helps observers perceive the
environment.
- Optic flow: your movement relative to the objects causes you to see the houses and trees
moving past when you look out of the side window.
1) Gradient of flow: the different speed of flow – fast near the observer and slower farther
away
2) Focus of expansion FOE: there is no flow at the destination toward which the observer is
moving
- Invariant information: information that remains constant regardless of what the observer is
doing or how the observer is moving. Optic flow provides invariant information because the
same flow information is present each time the observer is moving through the environment
in a particular way. Even when specific aspects of a scene change, optic flow and the FOE
continue to provide information about how fast a person is moving and where he is heading.
- Self-produced information: when a person makes a movement, that movement creates
information, and this information is used to guide further movement.
- Bardy & Laurent: experiment met ogen sluiten tijdens een oefening, bij experts ging dit meer
mis dan bij beginners, zij hadden nog niet geleerd om hun beweging te coördineren met hun
perceptie.
Retina/eye information
1. Image displacement signal
2. Motor signal
3. Corollary discharge signal
James Gibsons ecological psychology
- The senses don’t work in isolation
- Information provided by vision also plays a role in keeping our balance
1) Studying the acting observer
2) Identifying invariant information in the environment that observers use for perception
3) Considering the senses as working together was revolutionary for its time
- The moving observer creates information
- Self-produced information (door te bewegen creëer je informatie)
- The senses do not work in isolation (ze werken samen, bijv voor balans)
- ‘But even though perception researchers were aware of gibsons ideas, most research
continued in the traditional way- testing stationary subjects looking at stimuli in laboratory
settings. Of course, there is nothing wrong with testing stationary observers in the
laboratory, and much of the research described in this book takes this approach. However,
gibsons idea that perception should also be studied as it is often experienced, by observers
, who are moving and in natural settings, finally began to take hold in the 1980s, and today
perception in naturalistic settings is one of the major themes of perception research.’
‘ask not what’s inside your head, but what your head’s inside of’
Kijken naar de omgeving, niet wat er in je hoofd gebeurt
- Perception is direct
- Perception is for action
- Perception is of affordancens (handelingsmogelijkheden, what it offers the animal)
Experiment met aap
1) The monkey observed a small fixation light in the dark
2) Lights were turned on for half a second to reveal the object to be grasped
3) The lights went out and after a pause, the fixation light changed color, signaling that the
monkey should reach for the object
It adjusted its grip to match the object
The key result of the experiment is that there are neurons that respond best to
specific grips
- Visuomotor grip cells: a neuron that initially responds when the monkey sees a specific
object and then also responds as the monkey is forming its hand to grasp the same object.
Prehension (reiken en grijpen)
A) Perceive cup
B) Reach for cup
C) Grasp cup
- Experiment: aap kijkt naar lichtje en op het moment dat het licht uitgaat moet hij ernaar
reiken. Verschillende neuronen coderen voor soorten grip (hoe je grijpt)
Whole hand prehension
Primitive precision grip
Advanced precision grip
Finger prehension
- Neuronen lichten op als hij het zelf pakt én
als de aap iemand anders iets ziet pakken
- Parietal reach region PRR: contains neurons that control not only reaching but also grasping.
- Chapter considering the ways in which perceptual processes such as these are involved in
being physically active in the world
- How perception and action interact
- We need to consider action to understand perception
- Ecological validity: an ecologically valid experiment matches its stimuli, conditions, and
procedures to those present in the natural world (Gibson)
- Gibson’s ecological approach to perception: to determine how movement creates perceptual
information that both guides further movement and helps observers perceive the
environment.
- Optic flow: your movement relative to the objects causes you to see the houses and trees
moving past when you look out of the side window.
1) Gradient of flow: the different speed of flow – fast near the observer and slower farther
away
2) Focus of expansion FOE: there is no flow at the destination toward which the observer is
moving
- Invariant information: information that remains constant regardless of what the observer is
doing or how the observer is moving. Optic flow provides invariant information because the
same flow information is present each time the observer is moving through the environment
in a particular way. Even when specific aspects of a scene change, optic flow and the FOE
continue to provide information about how fast a person is moving and where he is heading.
- Self-produced information: when a person makes a movement, that movement creates
information, and this information is used to guide further movement.
- Bardy & Laurent: experiment met ogen sluiten tijdens een oefening, bij experts ging dit meer
mis dan bij beginners, zij hadden nog niet geleerd om hun beweging te coördineren met hun
perceptie.
Retina/eye information
1. Image displacement signal
2. Motor signal
3. Corollary discharge signal
James Gibsons ecological psychology
- The senses don’t work in isolation
- Information provided by vision also plays a role in keeping our balance
1) Studying the acting observer
2) Identifying invariant information in the environment that observers use for perception
3) Considering the senses as working together was revolutionary for its time
- The moving observer creates information
- Self-produced information (door te bewegen creëer je informatie)
- The senses do not work in isolation (ze werken samen, bijv voor balans)
- ‘But even though perception researchers were aware of gibsons ideas, most research
continued in the traditional way- testing stationary subjects looking at stimuli in laboratory
settings. Of course, there is nothing wrong with testing stationary observers in the
laboratory, and much of the research described in this book takes this approach. However,
gibsons idea that perception should also be studied as it is often experienced, by observers
, who are moving and in natural settings, finally began to take hold in the 1980s, and today
perception in naturalistic settings is one of the major themes of perception research.’
‘ask not what’s inside your head, but what your head’s inside of’
Kijken naar de omgeving, niet wat er in je hoofd gebeurt
- Perception is direct
- Perception is for action
- Perception is of affordancens (handelingsmogelijkheden, what it offers the animal)
Experiment met aap
1) The monkey observed a small fixation light in the dark
2) Lights were turned on for half a second to reveal the object to be grasped
3) The lights went out and after a pause, the fixation light changed color, signaling that the
monkey should reach for the object
It adjusted its grip to match the object
The key result of the experiment is that there are neurons that respond best to
specific grips
- Visuomotor grip cells: a neuron that initially responds when the monkey sees a specific
object and then also responds as the monkey is forming its hand to grasp the same object.
Prehension (reiken en grijpen)
A) Perceive cup
B) Reach for cup
C) Grasp cup
- Experiment: aap kijkt naar lichtje en op het moment dat het licht uitgaat moet hij ernaar
reiken. Verschillende neuronen coderen voor soorten grip (hoe je grijpt)
Whole hand prehension
Primitive precision grip
Advanced precision grip
Finger prehension
- Neuronen lichten op als hij het zelf pakt én
als de aap iemand anders iets ziet pakken
- Parietal reach region PRR: contains neurons that control not only reaching but also grasping.
