perception Flashcards
James Gibson
- James Gibson is the person who developed the Theory of Direct Perception.
- Gibson was an American Psychologist. His fascination for visual perception started at a very young age.
- Because his father worked on the railway, he would take him out on train rides. Gibson recalled being absolutely fascinated by the way the visual world would appear when in motion.
- In the direction of the train, the visual world would appear to flow in the same direction and expand. When Gibson looked behind the train, the visual world would seem to contract.
In 1941, Gibson entered the U.S. Army, where he became the director of a unit for the Army Air Forces’ Aviation Psychology Program during World War II. Of particular interest to him was the effect flying an aircraft had on visual perception. He used his findings to help develop training films describing the problems experienced while taking off and landing and visual aptitude tests for screening out pilot applicants.
Gibsons theory directly challenges the traditional approach to vision perception
- G challenged the traditional approach to visual perception, according to which The central
- function of visual perception is to allow us to identify or recognise objects in the world around us. This often involves extensive cognitive
- Processing: it is expensive to interpret what we see and then decide how to interact with it. What we see is a construct of the brain, an interpretation of the world that our brain has created based on information received + our visual knowledge of objects.
- For G perception is far more straightforward. He sees vision perception as a mean to pick up the information we need to interact with the world. It all arrives directly to our eyes – no need for interpretation.
This is why this view is considered more ecological; because it emphasises the role of perception in allowing interactions between the individual and his/her environment.
Gibsons theory of direct ecological perception
- Humans perceive the environment directly.
- «Direct perception is the activity of getting information from the ambient array of light. I call this a process of information pickup that involves . . . looking around, getting around, and looking at things»
Gibson (1979) theory of ecological perception
- Light is the key to vision.
- Light illuminates surfaces of objects in different degrees, depending on how they are in relation to the source of illumination.
- Objects absorb light and reflect it. There are differing degrees of illumination and shade. Depending on their surfaces (e.g. be smooth or irregular) objects will reflect light differently.
As light reflects off objects, it becomes structured, carrying information about their shape, position, and movement
Gibsons (1979) theory of ecological perception- optic array
- OPTIC ARRAY: (Ambient Array of Light)
- Is all the information from the environment that reaches the eye
- = Reflected (solid) angles of light from objects
- Optic Array is SUBJECTIVE – it depends on the observer’s position and orientation (ambient vision – looking around) and motion in the environment (ambulatory vision – sampling light by moving about)
Gibsons theory of ecological perception- criticism of traditional psychophysics
- He criticizes the traditional psychophysics approach of testing vision through static displays.
- e.g., classic tests of depth perception using static 2D stimulus presentations failed to predict student pilots’ performances
- Changes taking place in the surrounding field of light provide important information that static display miss.
- He emphasizes that organisms are seldom passive. Stimulation is often acquired through personal action, obtained rather than imposed.
Due to such active engagement with the world, stimulus input can be modified through both motor movement and movement of the sensory organs
Gibsons theory of ecological perception- information pick up
- INFORMATION PICK-UP
- The brain “picks up” information about objects directly = BOTTOM-UP process
- «The act of picking up information, moreover, is a continuous act, an activity that is ceaseless and unbroken. The sea of energy in which we live flows and changes without sharp breaks.» (Gibson, 1979/1986, p.240).
invariants
- Light provides us with higher-order variables, or invariants
- These are characteristic of the optic array that remain unaltered as observers move around the environment.
- Invariants are picked-up by direct perception.
- «Invariants are patterns in sensory information that are revealed when an organism engages in motor interaction with the environment» (Mossio & Taraborelli, 2008, p. 1328)
- In this theory, visual “stimulation” is viewed as a dynamic flux, which is produced by changes in the world or by changes in viewing position due to locomotion through the world.
- The dynamic flux produced by motion in the environment is variable and subjective. However, in all of this variability some characteristics will remain constant. These are the invariants of the optic array, and Gibson claims that these invariants are picked up by direct perception, and specify affordances to the perceiving agent.
what are invariants?
- Single lines are a basis for considerable information:
- Inform of edges, corners, horizons, outlines, borders, and other phenomena
- Lines do not inform of texture, shade, or reflectance
- but that information is also available in structured light
- The so-called “perceptual cues”, rather than being deductions of the brain, are also directly available in structured light, e.g.
- occlusion,
- linear perspective: parallel lines appear to converge as they recede into the distance
- distance from the horizon,
- Texture gradients:An extended surface with uniform spatial texture will project a retinal image with a non-uniform texture gradient that increases in spatial frequency as observation distance increases – more coarse and more detailed close to observer, denser and less detailed with increasing distance = information that allows us to judge distance
- Motion parallax (or Relative Motion): motion parallax is a change in position caused by the movement of the viewer. Motion parallax arises from the motion of the observer in the environment. It is perhaps easier to think of what motion parallax is by imagining yourself as a passenger in a car looking out the side window. The car is moving very fast down the highway. The objects very close to the window, such as the small trees planted by the highway, seem to rush by. Beyond the small trees, you can see a distant farmhouse. The farmhouse appears to move more slowly relative to you in the car. You know that the trees and the farmhouse are standing still; you are the object that is movingThis Information about objects is directly provided by the structure of light and does not require inferences.
vanishing points.
motion invariants
- Movement (from self and other objects) provides further information.
- This information is critical to guide our motion and interactions within the environment
- Objects (light) appear and disappear as one moves about.
- Motion gradients relate objects in the visual field with each other with respect to a point of fixation (or “Focus of expansion”).
- OPTIC FLOW: Changes in the pattern of light that reaches the eyes of an observer created when she moves, or parts of the visual environment move
- Objects “growing” or “shrinking” as an observer moves towards or away from them are Optic Flow Invariants, as the array will always transform like this under those conditions.
- A photo can illustrate optic flow if we take a step forward with a camera while the aperture is open (see illustration). The image of the environment moves past our eyes, and the camera, in the opposite direction.
motion information guides our actions: estimating heading direction
- As we navigate through the world…
- we must continually plan where we want to move
- we must try to avoid colliding with obstacles on our path.
- we must check that we are following the planned path.
- To do so we determine our direction accurately and efficiently.
- We rely on several visual cues to achieve this goal.
- And according to Gibson, these are changing patterns of light that our brain directly picks-up
radial outflow hypothesis (Gibson, 1950)
- When moving forward, the pattern of light reaching our eyes (optic flow) expands radially outward from a central point in the visual field.
- This central point is known as the Focus of Expansion (FoE) and corresponds to the direction in which we are heading.
- By detecting this expansion pattern, we can accurately navigate and adjust movement without needing complex cognitive processing.
- Gibson’s Radial Outflow Hypothesis explains how humans use optic flow to determine their heading direction while moving through the environment.
- Key Idea:
- When moving forward, the pattern of light reaching our eyes (optic flow) expands radially outward from a central point in the visual field.
- This central point is known as the Focus of Expansion (FoE) and corresponds to the direction in which we are heading.
- By detecting this expansion pattern, we can accurately navigate and adjust movement without needing complex cognitive processing.
- How It Works:
- Forward Motion:
- When walking, running, or driving straight ahead, objects in the visual field appear to move outward from the FoE.
- The speed of this movement depends on how close objects are: nearby objects move faster, distant objects move slower.
- Change in Direction:
- If we change direction (e.g., turn left), the FoE shifts accordingly.
- This shift provides real-time feedback for navigation, helping us avoid obstacles and stay on course.
global outflow
- Optic flow - describes the characteristic distribution of local motion directions across the visual field (appearance of objects as the observer moves past them)
- Gradient of flow - difference in flow as a function of distance from the observer:
- Objects at different distances move at different speeds on the retina of the eye.
- Focus of expansion - point in distance where there is no flow
- With the aid of optic flow, the brain calculates answers to motion-relevant questions
Gibsons radial outflow hypothesis
- This diagram illustrates optic flow patterns in different movement scenarios, as explained by Gibson’s Radial Outflow Hypothesis.
- Panel (a): Forward Motion (Expansion)
- The arrows indicate the optic flow pattern when moving forward through an environment.
- The Focus of Expansion (FoE) is at the center, where no motion is perceived.
- Objects in the periphery appear to move outward from this central point.
- This pattern helps determine heading direction—where the person or vehicle is moving.
- Panel (b): Backward Motion (Contraction)
- The arrows now show an inward flow pattern, which occurs when moving backward.
- Instead of expansion, objects appear to contract toward a central point.
- This is the reverse of the forward-motion optic flow and is important for judging depth and movement while moving away from a scene.
- Key Takeaways:
- ✅ Forward motion → expansion (optic flow moves outward from the FoE).
- ✅ Backward motion → contraction (optic flow moves inward toward the FoE).
✅ The brain uses these optic flow patterns to navigate, adjust movements, and maintain balance.
do people use flow information?
- Car fitted with instruments to measure
- Angle of steering wheel
- Speed of vehicle
- Direction of gaze of driver
- When driving straight, driver looks straight ahead, but not at just at the focus of expansion
- When driving around a curve, driver looks at tangent point on the inside of the bend
- This suggests drivers use other information in addition to optic flow to determine their heading
motion and retinal displacement
- Probably heading estimation is provided by two systems in the brain (Snyder and Bischof, 2010; Brain Research):
- One uses motion information (motion-based cues): provides navigational mechanisms and is fast and automatic (fast processing; unlimited capacity)
- One uses retinal displacement (scene-based cues): objects nearer the observer show stronger retinal displacement and are more informative. Provides navigational planning and re-orienting.
This is slower and requires attentional resources (i.e. cognitive load; limited capacity)
Brain area MST is tuned to optic flow
- Medial Superior Temporal area is part of the ‘motion system’ in dorsal extrastriate cortex - area V5/MT.
- Britten & van Wezel (1998) electrically microstimulated MST while trained monkeys performed a visual heading discrimination task (i.e. determine whether right or left heading optic flow)
- Microstimulation induced a significant shift of responses in the direction of the stimulated neurons
- In the experiment illustrated, the electrode was positioned in a region of MST containing neurons that consistently preferred leftward heading. Reduced proportions of right choices during micro-stimuliation and thus increased choices in favour of the neurons’ preference
- Human MST is strongly responsive to coherent optic flow (i.e. large patterns of dots moving with global flow motion)
- Gibson emphasised the role of optic flow in allowing people to move directly towards their goal.
- Certainly this must be important visual information for the brain, in fact there is evidence that the brain contains motion-sensitive neurons that react specifically to optic flow stimuli, translating the optic into a neuronal flow.
- a specific cluster of neurons in the medial superior temporal area is strongly responsive to optic flow.
Stimuli were large fields of moving dots, forming coherent global flow patterns. Random motion was used as a control.
affordances
- Information about the potential use of objects
- Intrinsic characteristics of the objects, which allow for human interaction
“affordances are opportunities for action that exist in the environment and do not depend on the animal’s mind” (Withagen et al., 2012, p.251)
affordances are perceived directly
- Gibson argued that an object’s affordances are perceived directly.
- Briefly seen objects (that afford a motor response) activate the visuomotor system automatically, without conscious perception, and potentiate a subsequent motor response.
- Do unseen objects that afford a motor response potentiate a subsequent and unrelated motor response?
- Gibson argued that an object’s affordances are perceived directly. Pappas and Mack (2008) presented images of objects so briefly they were not consciously perceived. However, each object’s main affordance produced motor priming. Thus, for example, the presentation of a hammer caused activation in brain areas involved in preparing to use a hammer.
- affordance effect:
- facilitated manual response to the target when it corresponds to the hand for action with the prime stimulus
more affordances for one object
- The theory that affordance is intrinsic in the object is oversimplified.
- What determines what affordance is perceived?
- mood – psychological state
- Creative processes – art and design
Learning and practice –
affordances in development
- James Gibson had little to say about the processes involved in learning what affordances will satisfy particular goals.
- His wife’s studies instead provided important insight in the developmental psychology of perception of affordances.
- Eleanor Gibson created the Visual Cliff, which is an apparatus to investigate depth perception in babies (but also animals, such as turtles, goats, rats, lambs, kittens, dogs, pigs, and monkeys).
- It involves an apparent, but not actual drop from one surface to another, It’s created by connecting a transparent glass surface to an opaque patterned surface. The floor below has the same pattern as the opaque surface. There is the illusion of a cliff while protecting the subject from injury.
- In the test, a child is placed on one end of the platform and the caregiver stands on the other side of the clear surface.
- If the baby had a developed depth perception skill, they should stop at the brink of the visual cliff. Instead if their depth perception was not developed yet, they would happily crawl through the clear surface.
- They observed that by the age of 8-months babies would recognise the visual cliff and stop at the brink – this means that a sense of depth perception is already developed at this age.
- Research evidences suggest that infants avoid the drop-off not because of fear of height (that develops later in childhood) but because they sense that they lack the physical skills to make the descent possible.
- They perceive the affordance of the visual cliff that signals the current pattern of locomotion must be interrupted and a new more complex pattern of locomotion must be instantiated in order to make the descent possible.
Karen Adolph did her PhD under E Gibson’s supervision - and continued leading research on infant locomotion and coordination to investigate the human development of perception of affordances for action and motor skills
affordances for locomotion
- Surface Friction vs. Slant
- Infants rely primarily on information for slant
- Touching and hesitation not increased by the sight of slippery surface
- Perhaps information for surface layout is more reliable
- Perhaps affordance for friction is learned more slowly through experience
- Walking infants are very good at perceiving affordance for locomotion over slopes.
- Surface Friction is another factor that determines affordance for locomotion and is quite relevant in its interaction with the Slope factor.
- In this study Adolph and colls addressed the question of whether infants’ perception of affordances for walking down slopes is based on both friction and slant.
- In three experiments the authors varied the steepness (or slant) of a slope and also the friction of the surface (from very slippery to high friction).
- All three experiments indicate that infants rely primarily on information for slant.
- Graphs indicate that with increasing steepness there was a much higher proportion of fall in the slippery condition (as expected). But we can see that the attempts to walk decrease only as a function of slope with no effect for slanting.
- The sight/feeling of Slippery surface fails to elicit more exploratory touching and more adaptive locomotor decisions.
- affordance for locomotion associated to slope steepness is impressively well perceived by Infants whilst they have difficulty in perceiving affordance of changing friction conditions and adapt locomotor decisions to it.
- One possibility for why infants rely more on information for slant than friction for controlling locomotion prospectively is that information for surface layout is more reliable (Adolph & Joh, 2009). Visual information for slant (and other variations in layout) are available from a distance; although it depends on the relative orientation of the walker in respect to the degree of slant.
- But information for friction is not available from a distance. It is acquired through learning about variations in shine, color, or texture associated to a given friction condition + feedback from contact between two surfaces (the sole and the ground). Without generating frictional force by touching the slope, infants see only a shallow slant that is typically navigable.
- Probably greater awareness of the significance of underfoot friction information and changes in the appearance of the ground surface (i.e. perception of affordance related to friction) may develop more slowly through walking experience and the combination of inputs that come from both touch, vestibular proprioception and vision.
- Until the infants rely primarily on slant to guide their decisions for walking down slopes.
why do young children err in judging affordance?
- Errors may stem from:
- less accurate perception – some affordances require more perceptual precision)
- liberal response criterion – e.g. what is judged as risky
- less sophisticated executive functions – low inhibitory control to refrain from exploring and attempting
- haptic exploration – need to learn to better use haptic and visual information
planning systems
- Activated before the initiation of movement.
- Selects the target and plans movement type and timing
- Both “Bottom-up” influence1 –
e.g., visual information, object’s affordances, visual context
and “Top-down” influence2 - conscious processes
e.g., individual’s goals, cognitive load etc. - Brain areas - different processes:
- inferior parietal lobule1: integrates visual representation of
the object + visual context = “Slow” process - Inferotemporal Lobe: object recognition
- prefrontal cortex2: planning and selection of
correct motor tools - Motor Cortex: Motor execution
Basal Ganglia: Motor programs
- inferior parietal lobule1: integrates visual representation of
control system
- During the execution of the movement (online)
- Accuracy, Adjustments – use of somatosensory feedback.
- Faster - uses little information (no context – only target)
- Not need for conscious influence.
- Brain areas:
- Superior Parietal Lobe: Control
- Cerebellum: Fine movements
- Basal ganglia: Motor programs
- Relies on:
- Efference copy (internal copy of a motor command)
- Proprioception (sensation relating to the position of body)
Visual perception (target object’s spatial characteristics)
different brain areas for the planning and control systems?
- planning and control of simple reaching and grasping actions
- fMRI study w 4 tasks
- different regions of the Posterior Parietal Cortex (PPC) are involved in either the planning (middle/posterior intraparietal lobe) or online control (superior parietal lobe) of the action
- There are very different types of actions, some of which are more complex than others and for each of which the neural networks involved in the action of reaching and grasping may be sligthly different.
- For example if your make a complex cake, the planning and control mechanisms involved will be different from a simple reaching and grasping action. In the first case, I may expect more areas involved, and more delay and disctinction between the onset of the two systems/mechanisms
- Glover decides to study the simplest action (reaching and grasping) – if one can see distinction between the two systems in this case, then can claim the distinction applies in more complex cases –
- Aim is to examine the planning–control distinction in humans using a task that eliminates any processing of higher order cognitive variables, in order to isolate the spatiotemporal kinematic elements of planning and control.
- fMRI study with four tasks: (i) plan a movement but remain still; (ii) plan and then execute the reaching and grasping movement; (iii) execute the movement immediately; or (iv) observe the target.
- i) a planning network including the premotor cortex, basal ganglia, anterior cingulate, posteriormedial parietal area, superior parietal occipital cortex and middle intraparietal sulcus; and (ii) a control network includingsensorimotor cortex, the cerebellum, the supramarginal gyrus and the superior parietal lobule.
- Planning involved a brain network located in:
- premotor cortex ans supplementary-premotor area, Insula - initiation of movements
- Dorsolateral prefrontal – decision of correct movement
- the medio-inferior parietal lobule (middle intraparietal sulcus and the posterior medial parietal area) – integration of object and context related information
- Control involved brain network in:
- Sensorymotor area - Somatosensory association cortex - supramarginale gyrus – integrates information from the body (muscles) and the cerebellum and adjusts movements accordingly.
- Superior parietal lobule – controls the body-object interaction using visual information and somatosensory information
- Cerebellum – fine movements
- TMS research can tell if the brain area is causally/necessarily involved
- TMS over superior parietal lobe disrupted control on adjusting action to changing size of object (Glover et al., 2005)
- TMS over inferior parietal lobe did not cause large disruption on a task where participants planned to reach out and touch target (Striemer et al., 2011)
- Perhaps IPL may be required for some functions of the planning process (e.g., selecting the goal of the action, selecting the target for the action).
However, it may not have causal role in programming the action
ideomotor apraxia
- Planning system compromised
- damage to the (left) inferior parietal lobe (but also other areas of the parietal lobe)
- poor at initiating purposeful movements towards a target (e.g. reaching/grasping object) –
- BUT control of the action is accurate
- Also deficits in properly performing tool-use pantomimes (e.g., pretending to use a hammer), imitation; communicative gestures (e.g., waving goodbye), response to verbal command
optic ataxia
- control system compromised
- Also known as Bálint syndrome
- Patient is not able to guide her hand towards object with help of visual information
- all aspects of visual guidance over reaching with the hand and arm get gradually lost (despite visual perception remains intact)
- damage to the superior and posterior parietal cortex
- Patients IG (Grea et al., 2002) and CF (Blangero et al., 2008) – could perform task well, but poor control if target suddenly moved location.
what is social cognition?
- Way humans try to make sense of the social world
- Our ability to process, store and apply information when we interact with other people in different social situations – Fiske & Taylor (1991)
- Umbrella term that encompasses concepts e.g. theory of mind, visual perspective taking, imitation, decision making, empathy, prosocial behaviour
- Breaking down social cognition:
- Social: representation Self and Other/s
- Understanding our own mental state and representations of self and beliefs and attitudes and those of others
- Cognition: Information about the social world needs:
- We need cognitive processing to be able to make sense of the world
- Working memory:
- Encoding
- Storing
- Applying information you gather to other people
- E..g to understand someone else’s behaviour you may have to refer to information that you have already stored
theory of mind
- Attribution of mental states to self and others (Premack & Woodruff, 1978)
- Work with chimpanzees to see oif they have theory of mind- first recorded publication referring to theory of mind
- Also known as mind reading or mentalising
- Also known as mindreading, mentalising
- Encompasses inferences on the basis of behaviour- we need to understand people around us and to do that sometimes you need to make inferences about what they are about to do or the reasoning behind what they have done related to behaviour
- Practical reasoning - attributions of:
- Intentions of other people
- Beliefs of others
- Desires of others
- Within the area of theory of mind, there are two systems that account to it: implicit and explicit
- Explicit: verbalise what you are thinking when you are trying to understand someones point of view and you use language for it
Implicit: more related to non verbal type of communication e.g.
- Explicit: verbalise what you are thinking when you are trying to understand someones point of view and you use language for it
implicit theory of mind
- Two systems account of ToM:
- Implicit vs. explicit mentalising (Apperly, 2008; Apperly & Butterfill, 2009; Frith & Frith, 2008, 2012)
- Evidence of implicit ToM in perspective-taking
- Can be inplcit thoery of mind in adults
- Dot perspective-taking task (e.g. McCleery et al., 2011; Qureshi, Apperly & Samson, 2010; Samson et al, 2010)
- Presented with a computer screen and a cue to tell you whether the trial is about yourself or someone else followed by a number cue
- Then have a scene in which an avatar in a room facing a wall with rede dots that could be in front of the avatar or behind it or both
- Number cue asks you to confirm whether the number cue matches the number of red dots (consistent trials)
- Sometimes the number cue coincides with the number of dots you or the avatar can see but sometimes the number of dots present in the scene does not match the cue before (you can see two dots but the avatar cannot- inconsistent trials)
- Usual finding is that participants tend to be really fast when it comes to consistent trials (avatar and yourself can see the same number of dots). They are much slower when they have to respond to inconsistent trials (the number of dots that you can see does not match the number of dots that the avatar can see)
- Interpretation of this findings is that this is evidence of implicit theory of mind- faster at adopting the perspective of the avatar than adopting our own perspective as participants take longer in the inconsistent trial- we consider the perspective of the avatar as well as our own perspective
This effect is found when participants make self judgments and do not require to take into account the avatars perspective- self consistency effect
domain specific vs domain general
- It seems that something automatic is going on in this task, but what is it?
- Automatic representation of what the avatar can see?
- Automatic attentional orienting?
- To test this the dot perspective task with another condition of arrow that does not have the characteristics of a person which encourages you to pay attention to one side of the avatar or the other
- Did this behaviourally but also with repetitive TMS which enhances performance in this task
- Results that were found- the arrow condition produces the same effect as having the avatar- able to show this both behaviourally in reaction times and also at a neural level with TMS
- No difference whatsoever in participants performance when they were making judgements about the number of dots or the avatar could see- regardless of the stimulus type (avatar or arrow)
- Challenges the implicit theory of mind interpretation because we do not tend to go around attaching or attributing mental states to inanimate objects like an arrow for example
- It does show that this task is more about attention reorienting rather than attributing mental states to another
We can argue that the characteristics of the avatar facing
implicit mentalising vs attentional reorienting
- Self-consistency effect replicated with non-social stimuli – arrow, both behaviourally (Santiesteban et al., 2014) and using neurostimulation rTMS (Santiesteban et al., 2017)
- Attention re-orienting underlies visual processing in this task
- No difference whatsoever in participants performance when they were making judgements about the number of dots or the avatar could see- regardless of the stimulus type (avatar or arrow)
- Challenges the implicit theory of mind interpretation because we do not tend to go around attaching or attributing mental states to inanimate objects like an arrow for example
- It does show that this task is more about attention reorienting rather than attributing mental states to another
- We can argue that the characteristics of the avatar facing forward and pointing with the shape of a woman is a salient type of stimulus that made participants look a certain way- more about attention reorienting
- Controversies:
- e.g. Schurz et al., (2015)
- fMRI study that claimed that they foud evidence of differences between the arrow and the avatar
- Integrating account:
- e.g. Capozzi & Ristic (2020)
- This task includes both trying to understand or attribute mental states but also attention reorienting- you need to sue attentional processes in order to understand the mental states of other people
- More or less where the debate is at the moment
the temporo parietal junction (TPJ)
- Temporal and parietal cortex meet- implicated in neural studies in a range of cognitive processes
- Key node within socio-cognitive processes including:
- Visual perspective taking (Aichhorn et al, 2006)
- Imitation inhibition (Spengler et al., 2009)
- Theory of mind (Saxe & Kanwisher, 2003)
- Also, key region involved in domain-general processing, working memory, attentional processes
- Attention re-orienting (Vossel et al., 2008)
- Also argue that it is involved in domain specific processing e.g. theory of mind
Brain region not solely involved in the social domain but also general cognitive domains
Imitation
- Imitation: The ability to replicate the action/ behaviour of another person
- It requires the merging of self-other representations- when you imitate another person you cionder what they are doing and have a mental representation of that action to be able to copy it
- Can be intentional but can also occur without our awareness
- Has been studied in the context of:
- Development
- Culture and evolution
- Cognitive Psychology
Social Cognitive neuroscience
imitation in social psychology
- Imitation = mimicry or the chameleon effect in social psychology (Chartrand & Bargh, 1999)
- In social situations we imitate actions (gestures/ voice patterns, e.g. regional accents) of others, seemingly without awareness
- Degree of mutual imitation correlates with quality of social interaction
Considered a ‘social glue’: promoting rapport, affiliation and group harmony
neonatal imitation
- Maratos (1973) and Meltzoff Moore (1977) found that newborns can imitate movements of a model - even when these movements involve moving body parts they cannot see
- tongue protrusion
- mouth opening and
- lip protrusion
- Rhesus macaques (N = 15) were tested on days 1, 3, 7 and 14 after birth
- They were shown 5 actions by human models including (for 20 seconds):
- Mouth opening
- Lip smacking
- Tongue protrusion
- Hand opening
- Eye opening
- Some infant monkeys matched tongue protrusion / lip smacking or both on day
<100 infants, longitudinally at 1, 3, 6 and 9 weeks of age Oostenbroek et al. (2016) Current Biology
from imitation to mind reading
- It has been suggested that imitation in infancy is subserved by an innate ability to read the minds of others (Tomasello et al., 2005)
- For decades, the data from neonatal imitation has fueled speculations of the ‘innate’ origin of the mirror neuron system (MNS)
The discovery of the MNS has led to suggestions that it forms the basis of social cognition – from action understanding to attribution of mental states to others
what are mirror neurons?
- Found by accident- fire when they first watch the experimenter grasp a cup- that action producied firing in the set of neurons and when grasping this object themselves the same set of neurons fire
- Mirror neurons fire both when we perform an action but also when we see the action being performed by somebody else
- Called mirror neurons because we are like looking at ourselves in the mirror- there is somebody performing an action, we consider the action that someone is performing and we are looking at it as if it is our own action that we are doing
- A set of neurons that become active during performance of an action and also during passive observation of a similar action (Gallese et al., 1996; Rizzolatti et al., 1996)
First observed in monkeys but there is evidence of a similar system in the human brain (Gazzola & Keysers, 2009; Iacobonni et al., 1999)
mirror neurons in humans
- The discovery of the mirror-neuron system (MNS) has lead to a whole new field of research that is now known as Social Neuroscience
- Several claims and counterclaims have been made regarding the origins of the MNS and its function in social cognition
- The imitation in infants data have led to the theory that the MNS is innate (e.g. Lepage & Theoret, 2007)
There are also claims that the MNS help us understand what another human is doing (Rizzolatti & Arbib, 1998; Rizzolatti & Craighero, 2004)
MNS- associative learning
- The innateness of the MNS has been challenged by empirical data from various research groups
- The alternative view of the origins of the MNS is that they are a product of associative learning – same kind of learning that produces Pavlovian conditioning – (Heyes, 2001, 2005, 2009; Heyes & Ray, 2000)
The Associative learning hypothesis suggests that each mirror neuron originates from sensorimotor experience – correlated experience of observing and executing the same action
MNS- role of experience
- Capoeira dancers, ballet dancers, or non-dance controls watch ballet or capoeira dance.
- Greater mirror system activation when watch own dance compared to non-experts, some generalisatio
Perceptual experience, motor experience or sensorimotor experience?