Chapter 7 | Taking Action

Pataasin ang iyong marka sa homework at exams ngayon gamit ang Quizwiz!

Define ecological validity

an ecologically valid experiment matches its stimuli, conditions and procedures to those present in the natural world

Define place field

areas of the environment within which a place cell fires

Define grid cells

cells int he entorhinal cortex that fire when an animal is in a particular place in the enviro, and which have multiple place fields arranged in a gridlike pattern

Define invariant info

enviro properties that do not change as the observer moves relative to an object or scene the spacing, texture etc. of the elements in a homogenous texture gradient doesn't change as the observer moves on the gradient the texture of the gradient supplies invariant info for depth perception

Define gradient of flow

in an optic flow pattern, a gradient is created by movement of an observer through the environment - gradient refers to the fact that the optic flow is rapid in the foreground and becomes slower as distance from the observer increases

Describe the mirror neuron system and action

mirror neuron system is important to our understanding of action -> not a matter of doing movement - many people have suggested that to understand action, the monkey brain is running a simulation of what it is like to run the action in our machine - this is the system that lets us understand other people's action, and through direct simulation in our own system, we directly appreciate what the other people are doing

Define mirror neuron system

network of neurons hypothesized to play a role in creating mirror neurons

Define audiovisual mirror neurons

neuron that responds to actions that produce sounds neurons respond when a monkey performs a hand action and when it hears the sound associated w/ this action

Define mirror neurons

neurons in the premotor area of the monkey's cortex that responds when the monkey grasps an object and also when monkey observes someone else (another monkey or experimenter) grasping the object there is also evidence for mirror neuron like activity in the human brain

Define head direction cells

neurons that fire based on which direction an animal is facing

Define place cells

neurons that fire only when an animal is in a certain place in the environment

Define border cells

neurons that fire when an animal is near the edge of an environment

Define landmarks

object on a route that serves as a cue to indicate where to turn; a source of info for wayfinding

Describe invariant information?

- concept of eco approach - info that remains constant regardless of what observer does or how they move - optic flow provides this kind of info bc the same flow info is present every time observer is moving through environment in a particular way - FOE always occurs at the point towards which the observer is moving - if observer changes direction, FOE shifts locations, but is still there - so even though specific parts of a scene change, optic flow and foe PROVIDE INFO ABOUT HOW FAST A PERSON IS MOVING AND where they are heading

Describe Lee and Aronson's swinging room?

- 13- 16 month old toddlers placed in a room w/ stationary floor but walls and ceiling that could swing towards or away from the child - this movement creates optic flow pattern in the right - optic flow pattern that the toddler observes creates impression that they are swaying forward - the only circumstance in which the entire world moves towards you is a situation where you are falling/moving forward - perception caused toddler to sway back, to compensate - when room moves back, optic flow creates impression of swaying backwards, so toddler sways forward to compensate - although a few were unaffected, 26% swayed, 23% staggered, and 33% fell down, despite the floor keeping stationary Adults - more extensive practice standing and maintaining balance - still effected by room 0 oscillating experimental room even as little as 6 mm causes adult subjects to sway approx in phase w/ movement - like puppets hooked to surroundings! - adults who didn't brace themselves could be knocked over by perception of moving room

Describe how senses don't work in isolation?

- Gibson felt that rather than thinking of the senses as separate, we should consider how each one provides info for same behaviours - your ability to stand up straight, and keep balance while standing or walking depends on systems that let you sense movement and position of your body relative to gravity - these systems incl. vestibular canals of inner ear and joint/muscle receptors - Gibson noted info provided by vision plays a role in keeping our balance - keeping balance is harder w/ closed eyes (MONICA), which occurs bc vision provides a frame of reference to help muscles make adjustments to maintain balance

Describe the research about mirror neurons in humans responding to why something is happening/ intention behind what is happening?

- Ie., coffee shop gal, - when she reaches for coffee cup, we might wonder why she is reaching for it - different interpretations can be assoc. with same action - Iacoboni and coworkers provided evidence that response of mirror neurons can be influenced by different intentions in an experiment where they measured brain activity as they watched short clips - stills for two intention films show hand reaching in to pick up a cup, but in one scene, table is neatly set, food untouched, w/ cup full of tea, but bottom panel there is a mess, food is eaten, cup looks empty - HYP: viewing top = infer that the person picking up the cup intended to drink from it, and the bottom film viewing would lead viewer to infer person was cleaning up - also viewed control vids: context film showed table setting, action film showed hand reaching to pick up isolated cup. these were shown because they contained visual elements of intention films, but didn't suggest intention - brain activity compared in intention to activity in context and action - finding: intention films caused greater activity than the control films in areas of the brain thought to have mirror neuron properties - amount of activity lowest in action, higher in cleaning up, and highest for drinking condition - increased activity in the Intention conditions = concl that mirror neuron area is involved w/ understanding intentions behind actions shown in films - if they were just signalling action of picking up the cup, then a similar response would occur refardless of whether context surrounding cup was present - so, the mirror neurons code the "why" of actions and respond dif to dif intentions

Describe the studies about the neural activity in the brain during landmarks?

- Janzen and Miranda van Turennout - subj studied film sequence that moved through computer sim. museum - subj told they needed to learn their way around to be able to guide a tour through it - objects, were located along the hall of this museum - decision point objects marked placed where it was necessary to make a turn - non decision objects were loc. at places where decision wasn't needed - after studying layout, subj were given a recognition test while in fmri - saw objects that had been in hallway, and some they've never seen - brain activation measured as they indicated whether they remembered the object - parahippocampal gyrus, implicated in navigation indicates that for objects that the subj remembered, activation was greater for decision point objects than for non - decision point landmarks are more likely to be recognized, and also gen increased brain activity - decision point objects also increased brain activity, even if they were not remembered during test -conclusion: brain auto distinguishes objects but also how relevant object is for guiding navigation - if you are navigating route you have travelled before but not confident, parahippo cgyrus may be highlighting landmarks that indicate when you should turn or not, even if you don't remember seeing them before

Criticisms of the action -specific perception studies?

- question whether perceptual judgements measures were measuring perception - may be affected by judgment bias, caused by expectations about what they think would happen in a particular situation - so expectation that objects could appear farther when person has difficulty walking might cause them to say it appears farther, even though perception of distance was unaffected

Describe the studies about what info we use to stay on course while driving?

- Lee and Land - automobile fitted w/ instruments to record angle of steering wheel and car's speed, and measured where the driver was looking w/ a video eye tracker - according to Gibson, foe provieds info about place towards which a moving observer is headed - Land/Lee found that although drivers look straight ahead while driving, they tend to look at a spot closer to front of car, not directly at the foe - SO, because they don't look at further FOE, it may be that drivers take advantage of other info + optic flow to determine direction headed - Recorded what drivers look at as they negotiate a curve 0 task is well suited to detect info and strategies beyond optic flow bc driver's destination adn FOE change as the car round the curve, so foe IS POOR indicator of how car should be steered - found that when going around the twist, drivers don't look directly at road, but tangent point of curve on the side of the road - this lets drivers constantly note position of car relative to lines at the side of road 0 by maintaining constant distance between car and lines, driver can keep car headed in the right direction

Someone riding a bike as perception

- Nick rides a bike - where is he going? how does he know where he is going? - asking qs about perception in this way, perception takes on a different flavour - classic story is that action is deemed an output stage that helped us influence action and perception -> action shapes neural processing as well, and can effect neural processes based on where we put ourselves w/ world

What are some of the continuing research around mirror neurons?

- Proposition 1. mirror neurons signal what is happening and intentions behind various actions - 2. mirror neurons help us understand communications based on facial expressions, emotional expressions, gestures used while speaking, meanings of sentences, and differences between self and other - 3. mirror neurons play important role to guide social interactions

Describe the research around topographical agnosia?

- TA = condition where you cannot recognize landmarks in the real world - commonly due to loss of tissue in parahippocampal gyrus - Rainville and coworkers conducted experiment w/ our mans FG, who was severely impaired in his ability to recognize famous landmarks and landmarks for his hometown, where he had lived for 30 years - researchers first led FG along 2 km route through unfamiliar city, and then asked him to walk it alone. of the 21 decisions along the route, FG turned the correct direction 10 times, a rate not dif from chance - members of a control group turned in correct direciton 18.8 times - so FGs inability to recogn landmarks was a problem with way finding, a result we may have expected given the importance of landmakrs in fMRI studies - when researchers asked FG to navigate his hometown, he could - however, he used street signs and printed building names to help keep track of his location in a mental map to find his way around - there are neurons in brain that map the environment

What is affordances?

- another of Gibby;s concepts (his eco approach involves ID connections between perceptual info and performance of actions, like optic flow and actions) - info that indicates how an object can be used - what it offers, provides for, or furnishes - a chair or something to sit on affords sitting - perception of an object incl not only phys properties that enable us to recognize object, but also info about how the object is or could be used - ie., looking at a cup, you might see it as round, white, cup, 5 in high, w/ handle, but perceptual system woul respond w/info like can be picked up, filled with liquid, or can be thrown - beyond just recognizing cup, it guides interactions w/ it - potential for action is part of our perception of an object

Describe the research measuring optic flow?

- asks observers to make judgments regarding where they are heading based on computer generated displays of moving dots that create optic flow stimuli observer must judge, based on optic flow stim, where they would be heading relative to a reference point - images depicting these represent the movement trajectories of individual dots - longer lines = faster movements - depending on trajectory and speed of dots, different flow patterns can be created - as shown in the figure, the flow indicates movement directly to the vertical line on the horizon, they flow in the second image indicates movement to the right of the vertical line - observers viewing stim like this can judge where they are heading relative to the vertical line within about 1 - 0.5 of a degree

Draw and describe the relationship between movement and flow?

- basic principle behind much of our interaction w/ enviro - pg 151 - Movements -> creates flow -> flow -> info for guiding further movement -> movement

Describe mirror neurons and "rational" imitation? L

- claims that mirror neurons and infants very early on, even before language acquisition (up to 14 mos old), the system and idea of simulating others actions and will be equipped w/ it will show that simulation and supports will look at rationale of other people's actions 2 conditions Setup: experimenter, box w/ a light on it that if you push on it it will turn on preverbal infants that have not acquired language are exposed under dif. conditions in both conditions, experimenter turns light on...with their head - why tf would you use your head?! The fact this is a weird action is intentional - there are two situations: in both cases, experimenter is wearing a blanket. In one, she wraps herself in the blanket saying it is cold, and her hands are occupied, and she turns light on with her head - in the other case, her hands are free, and she still turns the light on with her head - if the child is given opportunity to turn light on, do they use their head or hands? - they are making a distinction of how humans learn from one another - if the goal is just to turn on the light, we'd just use our hands - but at what age does the ability to understand the rational intention to perform an action come about

What does wayfinding consist of?

- complex process that involves perceiving objects in the environment, remembering objects and relation to overall scene, and knowing when to turn and in what direction

What are the two types of learning the rational imitation study shows?

- copying has two defs - true imitation: one human watching another prdocues an outcome of action w/ the same action -emulation: a human can reproduce the same outcome as another human - imitation is what makes humans special - many creatures can emulate, but won't necessarily do it with the same action - only humans can replicate output of motion with the same action - all of language and culture depends on this skill - for lang to work, we have to reproduce sounds and in the same way - to learn how to use tools and build stuff, it is not enough to reproduce outcomes, we have to use them in the same way - esp in dancing, you cannot produce the same effect, you have to produce it in the same way, we are truly imitating, we aren't just emulating

Okay, but why are mirror neurons firing?

- could be responding to anticipation of receiving food, not the specific action - not reasonable, bc type of object made little difference - the neurons responded the same when monkey observed experimenter pick up an object that wasn't food - could it be responding to the pattern of motion? Probably not, it doesn't respond when the experimenter picks up food with pliers - further evidence that they are doing more than just responding to a particular pattern of motion is the discovery of neurons that respond to sounds ASSOC WITH ACTIONS

What was a decision vs non-decision point landmark for Sahar Hamid's maze study?

- decision: objects at corners where subject had to decide which direction to turn - non-decision: objects located in middle of corridors providing no crit. info about how to navigate

What is the major goal of the eco approach to perception?

- determine how movement creates perceptual info to guide and further movement, and helps observers perceive the environment

Describe the ecological approach to perception?

- dominant perception research method throughout the 20th century was to have stationary observers look at static stimuli in the lab situation - one group, led by JJ Gibson, argued this traditional study method lacked eco validity - placing subj in small testing rooms to look at simple stimuli ignores how a person perceives when they perform natural, real world tasks like walking through a hallway, riding a bike, or landing an airplane - perception was argued by gibson/eco psychologists to have been adapted to move within and act upon the world - better approach = study perception ins situations where people move and interact w/ environment - bc it focused on perception in natural contexts, it is called eco approach

Describe self-produced info

- eco approach - when a person makes a movement, that creates info, and info is used to guide further movement - ie., as you drive, movement of car provides optic flow info, and observer uses this flow info to steer the car

Describe Sahar Hamid's study on how subjects used landmarks to navigate a maxelike environment?

- environment was displayed on computer screen where pictures of common objects served as landmarks - subjects first navigated through maze to learn the layout - then, told to travel from one location in maze to another (testing phase) - during both phases, eye movements measured using head mounted tracker - maze contained both decision point landmarks and non-decision point landmarks - eye tracking showed subjects spent more time looking at decision point lm's, probably bc they are more important for navigating maze - when maze performance was tested w/ half of landmarks removed, removing landmarks that had been viewed less (the middle of the corridor ones) had little effect, but removing the ones the observers had looked at longer dec. performance

What are our goals for this chapter?

- expand on the idea that perception is an activity - examine how action generates information for us in states, and how info is processed by ns - concepts important for thinking about perception as brain-body-enviro interaction

Why is there individual differences in wayfinding?

- experience - people who have practiced getting from one place to another in a particular environment are good at finding their way, and there are physiological consequences to this ability

L describe the early demonstration of the facial movement copying in an infant?

- experimenter made different faces and showed them to infants (tongue out, wide mouth, puckered) - infants were 12 days old - infants cannot explore actions, or coordinate actions, and have poor vision - striking demonstration is that the infant, after a few attempts by experimenter would produce the same face - replicability of finding is in question, and how robust this is as a phenomenon - but other studies have shown these results - this means we seem to have a system prepared to map another people's action onto our own ns - imitation through simulation! how sophisticated is our mirror system upon brith? - seem to come equipped w/ sophisticated mirror system - suggests understanding people through simulation = core feature of human brain

L What is a mirror neuron?

- fires in the organization of action, like picking up peanut - and fire for action, grabbing the peanut in a particular way - not only to the sight and seeing particular action, and sound of particular action -> so sound of peanut as they crack, and when experimenter cracks it - are they perception or action cells? - can see that these divisions, as humans trying to understand own minds, will break down - one of the reasons we changed the idea that something comes into brain and we change the action, which is why we tell a more dynamic story where perception and action are folded in to each other

Describe the firing pattern of an audiovisual motor neuron?

- fires when monkey sees and hear experimenter break peanut - when monkey just sees experimenter break peanut - when monkey hears sound of breaking peanut - when monkey breaks peanut - just HEARING a peanut break or seeing a peanut be broken causes activity that is also assoc. w/ perceiver's action of breaking a peanut - so neurons are responding to what is "happening" breaking a peanut, not to the specific pattern of movement

Describe May Britt and Edvard Moser's study about the other types of cells that aid the coding of cognitive maps and animal's location?

- grid cells entorhinal cortex - firing rate of grid cells increase based on animal's pposition - unlike place cells, grid cells have multi place fields arranged in a regular, grid pattern like the cells in the one pic w/ hexagon - exact function of gridd cells are unknown - due to spatial regularity, they are likely to be able to provide info about direction of movement - so, movement in arrow would lead to reponses in orange, blue, green cell, but movements in other directions = different firing patterns - so, grid cells may be able to cod edistance and direction info as animal moves

Describe Repacholi and Meltzoff's study on 18month olds?

- had the kids observe adult carrying out various actions w/ a specific noise, like squashing a plastic cup, which made a popping or scraping noise - another person, called the emoter, was in the room, and commented on adult's actions - in anger condition, they made unpleasant faces and negative comments - in neutral condition, their expression was neutral and said neutral or positive things - question: would child imitate the adult's actions when given an opportunity - answer depended on whether the emoter was angry or neutral - children were less likely to imitate adult when emoter was angry - so, at an early age infants begin using top-down info, based on the situation they are in, to determine whether and how often they should imitate others same thing adults do when tehy predict others' actions, and perceive the enviro int erms of their ability to act on it

How do the dorsal and ventral streams work to allow us to reach and grasp?

- idea that there is one stream for perceiving and another for acting on them - as you reach for something, you first ID it among other objects, which employs the ventral stream - once the object is perceived, you reach for it, taking into account its location on table (dorsal path) - as you reach, you avoid the other objects, positions hands and fingers to grab the object (also dorsal) taking into account the perception of the grabby appendage ) ventral) - then, you lift object w/ the right amount of force (dorsal), taking into account hw heavy it is based on your perception of it (ventral) - reaching and picking up something involves perceiving position of the thing, shaping hand and fingers relative to thing, and calibrating actions to accurately grasp cup and pick it up

What is the evidence where person hasn't carried out action, but has an expectation about how difficult it would be to perform action effects it? ?

- if ppl who were fit and those who weren't were asked to estimate distances - Witt asked ppl w/ chronic back or leg pain to est. distance from various objects in a long hall - chronic pain group over estimated distance from objects reason = over time, people's general fitness level affects perception of difficulty of carrying out activities, which affects their perception of it - so people w/ pain that makes walking difficults will perceive object as being further away, even if they are just looking at an object

Describe how movement creates perceptual info?

- imagine driving down empty street - everything around you would be stationary - however, even though they aren't moving, your movement relative to the objects causes you to see houses and trees moving past when you look out the window - the road ahead is moving towards you, and as you cross a bridge, its sides, top and road below move past you opposite to the direction you are moving

Where are the mirror neurons located?

- in the PFC - italian researchers found neurons that "mirrored" - knew these frontal lobe cells coordinate action, so this wasn't a big deal - mirror neuron does do that, fires for reaching and grasping, but the surprising finding is the collection of cells that do this when OTHER people/monkey observed the action - response occurring when performing the action and observing the action only neurons that have made it into a pop culture - research is ongoing, and some conclusions have been tempered - still fun and cool!! -

Results of the mirror neurons and 'rational' imitation? L

- in the occupied context, she has a good reason to use her head to turn on the light - in the other one, it makes no sense - is an infant going to interpret this action as being intentional? Since hands are free, will mirror system allow them to understand and interpret this as "there's a good reason to use head instead of hands that is easy" - when i turn on the light, will i do what they have done in terms of intention and goals, and the exact action, or will i just focus on outcome and just *turn the light on* - in hands free condition, more infants are using heads than in the hands occupied condition - if hands are free, there is more imitation -> not just interpreting action as researcher wants light on, there is some complex action happening and there must be a good reason, so I will reproduce it in the same way -> we are the only beings that do this! - non humans will turn light on, but not in a way consistent with rationality, will udnerstand there is outcome and will just do the thing to get outcome we are the only ones to exactly imitate, our system is made to map these behaviours onto our own system

What are important...qualities? of movement information?

- info is always available, the world out there and our minds/brains/bodies are stable enough that through movement, we can always generate information - perception is exercise as acting in the environment to exercise info available by our perceptual systems

Two Gibsonian ideas of info and movement?

- info is self-generated, produced by organism acting in certain ways - universe is structured and non-random -> something consistent in the world, and something consistent in us -> we move in a particular way - info that is key for perception doesn't align w/ intuitions about what the senses are - how is info generated from multiple senses?

Describe the research by rizzolatti on mirror neurons?

- investigation of how neurons in monkey's premotor cortex fired when monkey performed actions like picking up a toy or piece of food - goal = determine how neuorns fired as monkey carried out specific actions - observed that when one of the experimenters picked up a piece of food while monkey watched, the neurons fired - neurons that fired to observing the experimenter pick up the food were the same ones that had fired earlier when the monkey had picked up the food - this led to discovery of mirror neurons - called this bc the neuron's response to watching the experimenter grasp an object is similar to the response that would occur if the monkey were performing the same action - only a small response if monkeys looked at the food, or watched the experimenter grab it with something else, so mirror neurons can be specialized to respond only to one type of action like grasping or placing an object somewhere

Describe the studies about affordances?

- looks at people w/ brain damage - Humphreys and Riddoch -tested Mp, who had damage to temporal lobe + impaired ability to name objects -MP given cue, either name of an object or what it was meant to do/indication of its function - shown 10 objects and asked to press a key as soon as he found an object that matched the cue Mp ID the object more accurately and rapidly when given cue that referred to object's function - concl = MP using knowledge of objects affordances to help him find it - it is likely that he would be able to use info about obkect's function to help take action w/ respect to object - other people w/ temporal lobe damage also can't name, but can interact and use objects

What are the results of the intention to film studies? L

- main = what is happening to mirror networks when exposed to intention film - frontal mirror neurons inc activity - not just cues or action, has to be alignment for these mirror regions - when the action makes sense, then the mirror system is more active - the system in humans is not encoding actions, or sending instructions for how to hold your grip, or processing complex scenes, activity signals intentional action - researchers were *stoked* bc it suggests intentionality is something that the brain is pulling out for us in a direct fashion - potential reps of people's intention

L What are affordances?

- main thing: all of this research on representations that support this mundane activity, a main take home is that the brain represents affordances - affordance = particular usage - core idea -> things in the world, objects, locations, and other people allow for certain types of interaction - things in the world furnish different types of opportunity for action - modalities allow us to extract what opportunities there are for acting on the world: size, distance, movement, etc. - brain is extracting opportunities and action/possibility for action - representation isn't just the physicality, its about intentions of action - when you pick up cup, it just comes together in cautiousness

Describe how senses do not work in isolation?

- makes no sense to talk about senses in isolation hehe - balancing on one leg w/ eyes closed - we can keep balance well in everyday life - swinging room experiment: explore or understand how our different systems work together - floor is stationary, and move the room (either in or out) - generation of optic flow, pitting generation of information against other sources -> like the vestibular system, and other sources in the body - optic flow is generated through action, and is reliable about where we are going in the environment, and when this is stunted we make funny compensation - if room is coming towards you, the only way this happens is if you fall forward, so you move back to stop that, toddlers fall over - toddlers, as soon as they move independently, has optic flow available to them quickly in development

What is the debate about the function of mirror neurons?

- mirror neurons play important roles in human behaviour, others are more cautious: when feature detectors that respond to oriented moving lines were discovered, some researches proposed that is how we perceive objects. Later though, when neurons that responded to faces, places, and bodies were discovered, researchers revised initial proposals

What is the set up of the Intention film study ? L

- mirror system is helping us - by having a brain that directly maps someone else's action onto our own nervous system, we get direct insight about goal of an action - Study that captures: fMRI, measures blood flow to brain, and whether particular areas are measured - interested in those that showed mirror properties, specifically frontal areas - different films watched, experimental films -> the plate and teacup - one is before tea, all the food is laid out before tea - after tea = mess, crumbs everywhere - both provide context - additional control film = action, removes cues to a scene, and looks at what the brain is doing when the person picks up a cup - pincer or precision (finger/thumb) or power grip (all four fingers) - control film for context implies action, tje before tea you would go to drink it, after tea you would go to clean it up - in action control, one is drinking tea grip (claw/power), the other is cleaning up after tea grip (pincer) - intention film, hand is on cup and cup is full, situation is defined by intention to drink - other set up w/ the mess = that this scene implies the person is cleaning up

Describe the parietal reach region?

- most important areas for reaching and grasping - area in monkey and human parietal cortex involved in reaching for objects 0 contains neurons that control reaching and grasping - may be a number of different parietal reach regions in human parietal lobe

What are the characteristics of wayfinding?

- multifaceted - depends on numerous sources of info and is distributed through many structures in brain - makes sense bc wayfidning involves seeing and recognizing objects along a route, paying attention to specific objects, using info stored from past trips through enviro, and combing all info (perception, attention memory) to create maps that relate to what we are perceiving and where we need to go next

Describe how the brain represents space?

- neurosci of eco psyc is developing - goal was to determine how the brain reps space - "brain's gPS system" -> short story is that, like HUbel and Wiesel, scientists were looking at output of single cells, but not as animals looking at things on a screen, but measure single cells as animals move - square boxes = environments Discoveries: 1. Hippocampus - as animals move around space, cells in regions code the position w/ respect to space in a particular way - left box -> schematic repping room and gray traces = movement around room - while recording from hippocampus, some cells would respond when in a particular location in the room - coloured dots are all locations where one cell would fire - investigators realized that cells have preferred tuning, not to visual information or to balance or proprioceptive vision, but to where animal was in room - called place cells -> found where they were in cells preferred place 2. Surrounding hippocampus cortex - other cells code relationship of animal to space, but box represents room, and traces = animals moving, but responses aren't for one specific place, but multiple - reaches a part of the room where orange cell fires, but another place in room where it fires, and each time it stops, but multiple cells fire to different places - researchers uncovered encoding pattern, called them "grid" cells, because cells rep space in a gridded form - cell represents space on a grid - when u have many cells, u get gridded rep of the space - both of these cells, place/grid cells, are the most widely studied and critical studies that help us think about how brain generates info through environment, when you enter new room, a cell will fire in a particular corner, or you can move around the room, and there is a cell workin to rep room in gridded fashion - other cells also fire for direction the animal is looking - others like border of spaces

Taking action - what does it mean to "act to perceive"

- objects are perceived in context, many cues that we pick up to activate schemas, had strong perceptions of shoe, despite it being a blob -> but image of blob didn't change, but top down altered our perception - one of the stories = perception needs to be a brain body interaction, by acting we help create perceptions

Describe the way researchers have investigated the link between perception and action in infants?

- one way to investigate link is to look at how infants and young children learn to imitate the actions of others - we seem to be capable of imitating the actions of others from birth - Demo: - Meltzoff and Moore showed that a group of infants aged 12 - 17 days imitate the facial expression of an adult model - this may seem like a simple act, but imitating reveals complex mental processing on the part of the infant - to imitate adult's facial expressions, infant has to have the ability to see, control facial muscles, and have the mental ability to transform what is seen visually into an action that can be performed nonvisually (since we cannot see our faces) - so, this is not the result of an automatic perception-> action conversion, it is purposeful and goal oriented: we imitate others bc doing so teaches them how to perform and complete new tasks

Eco approach phenomenons?

- optic flow - invariant info - self produced info

What are cues available with movement according to Gibson psychologists?

- optic flow -- idea is that, when we are moving through environment, there are consistent structured changes to image that give us information about what is happening in the world -- visual field/contents of field will expand in a particular way -- stuff that is closer to us expands/moves by us at a faster rate that is farther away -- car on a hwy -> the fence poles are whizzing by you, but far away trees are moving more slowly -- image on right is updated version with a lot of blue arrows - as people are moving through environment, they look at direction of optic flow and length of arrows = speed and direction -- can only get this information by moving, cannot passively receive this

How does a person stay on course as they are walking towards a specific location?

- optic flow yes, can provide invariant info regarding trajectory and speed - strategies can play a role in maintaining one's heading - visual direction strategy is one where observers keep body pointed to target, but if they go off course, they will drift to the left or right. Walker can correct course just by realigning to body to target

What is the problem of measuring perception?

- our measurement is always based on ppl's responses, so there is no guarantee that these responses accurately reflect what a person is perceiving - may be some instances where responses reflect what they think they should be perceiving, not what they are - researchers try hard to conduct experiments where effects of action have been demonstrating even w/o expectations or task demands - a reasonable concl, taken into accoutn, is that in some experiments subjects' judgments may be affected by expectations, but in other experiments may reflect a real relationship between ability to act and their perception

L Physiology of reaching and grasping/affordance?

- parietal reach region PRR -- region also important to coordinate rest of brain to coordinate and reach out to grab something - regions of prefrontal premoto neurons (mirror neurons), code complex aspects of action - MT area/gyrus that encodes aspects of movements and object, supporting our ability to interact w/ objects like cups

- why is it harder to balance on one leg?

- perceiving being upright isn't just one system, but vision - at first its okay, but we start to sway - even simple perception of uprightness in the world is coming from more than one place

What is the major action we do?

- picking things up! - reaching and grasping are directed to specific objects to accomplish specific goals (ie., grasp doorknob to open doors)

What are the other cells that make a map of our environment?

- place and grid cells likely work tog bc they areconnected w/ each other, even within a single synapse - head direction cells fire depending on direction animal is facing - border cells fire when animal is near edge of environment

Describe Tolman's preliminary rat studies on the Brain's GPS?

- rat was place in a maze - initially explored it, running up and down the alleys - after initial period, rat was placed at A and food was placed at B, and rat learned to turn right at intersection to obtain food - according to the classic learning theories, rewarding rat w/ food everytime it turned right would strengthen turn right response, and inc the chances of it turning right to get food - however, after precautions that rat couldn't smell food, Tolman placed rat in a different area of the maze, and the rat turned left at intersection to still get food at B - this shows that rat doesn't learn sequence of moves to get food during training, but made a cognitive map of the spatial layout of maze to get food

Why are place and grid cells important? What are the research that supports humans may have grid cells

- recent experiments suggest similar cells may exist in humans, not just rats - determining whether human cells are similar to rats poses challenge of recording electrical signals as we move around - Jacobs and coworkers found neurons in humans similar to the grid cells by recording from single neurons in patients who were being prepared for surgery - patients were confined to beds, so couldn't navigate, but they were fitted w/ vr and searched for hidden targets - red areas in image )159) show high firing frequency, which form a grid pattern similar to the hexagonal shape in rats - human patterns ar enoisier, but results from 1- dif patients = conclusion that these neurons help humans create maps of enviro - cells similar to rat place cells also have been discovered

Describe the research in monkey's parietal lobe?

- recordings from single neuron's in parietal lobe - neurons are in an area next to parietal reach region that respond to specific hand groups - monkey hand grip experiment: Fattori and coworkers -monkey observed small fixation light in dark - then, lights were turned on for half a second to reveal object to be grasped - lights turned out, and then, after a pause, fixation light changed colour, signalling the monkey to reach for object - key part = monkey reaching for object in the dark - monkey knew what the object was from seeing it when the lights were on (round ball, in eg) - when it reached for object in the dark, it adjusted its grip !! to match the object - diff. objects were used, each which required a different grip - key result = there are neurons that respond best to specific grips - one neuron responded best to whole hand pretension (like grabbing ball) - different one liked primitive precision grip (thin blocks) - others liked advanced precision grip 9grabbing something in something else), and others liked just finger prehension - when neurons were firing, the monkey was reaching for object in the dark, so firing =/= visual perception

How did Melvyn Goodale describe that action is crucial for survival ?

- researchers understand brains evolved not to enable us to think, but to move, and interact w/ world- all thinking (and perception) = serves actions - perception may provide valuable info, but taking a step beyond perception + acting on info lets us survive so we can keep perceiving - we can take enjoyment in simply perceiving an object or seen, but the vast majoirty of our experience involves two processes: perceiving an object/scene, and taking action towards objects within the scene

How do mirror neurons signal intentions (human )

- response of neurons may be determined by chain of motor activities that could be expected to happen in a particular context - ie., picking up a glass to drink, next expected actions would be to bring cup to mouth and drink, but if intent = clean up, the action may be to carry the cu[ pver tp the sink - so mirror neurons responding to dif intentions are responding to action happening plus sequence of actions that is likely to follow - exact functions of neurons in humans still being researched

Describe the follow up experiment to the monkey hand grip (gorilla grip...hehe) experiemnt?

- same monkeys - neurons were discovered that responded not only when monkey prepared to grip specific object, but if monkey viewed that object - ex of the visuomotor grip cells is a neuron that initially responds when monkey sees specific object, and then also responds as monkey forms hand to grasp object - neuron is involved in both perception (ID object and affordances) and action (reaching and gripping object)

Describe Witt and Proffitt's study on the action specific perception hypothesis? What are the other studies in sports + action specific perception?

- series of circles presented to softball players just after finishing a game - asked them to pick circle that best corresponded to size of a softball - compared players' estimates to batting averages in the game, and found the batters who hit well perceived the ball bigger than batters who didn't hit well - tennis: tennis players who have recently won report net is lower - football: players who were successful at kicking field goals est. goal posts to ve further apart -- ^ is really interesting, bc effect occurred only after they had attempted 10 field goals. before they began, est. of all kickers were the same - all done by making people make judgements after they do well or poorly

L How do we locomote?

- study similar to pin the tail on donkey - put people in a room, get people to point to target, and then blindfold them and move them in particular direction, and estimate where the target is - overall, there is no vision, so representation and perception of space is derived from information coming from the body - eco psychologists like talking about how perception <=> w/ our behaviour, but people can still estimate target pretty well, so space can be derived from just the body, not vision - type of wayfinding - contrasts w/ navigating by landmarks - so we don't necessarily need landmark cues, we can also use bodily cues

What are the "revolutionary ideas" of Gibson?

- studying acting observer - id invariant info in enviro that observers use for perception - considering senses as working together - most research sticks to stationary subj looking at simple stim, but his idea that perception should be studied as experience, by naturalistic observers, began to take hold in the 80s, and perception in naturalistic settings is one of the major themes of perception research

Describe the study by Jared Miller and Carlson + other studies that demonstrated our better memory for decision point landmarks

- subjects learned a walking route through a museum sim filled w/ exhibits that was on a computer - subjects were asked to create written description of route or draw a map, incl. as many exhibits as possible. exhibits located at decision points were included more often than those at non-decision points - decision point landmarks more likely to be reproduced later, and more likely to be recognized (this concl. studied at U Penn where subj learned a walking route around campus) - in another study, subjects were more likely to recognize pictures of building located at decision points than those in the middle of the block

Describe Meltzoff's experiment demoing that babies don't imitate exactly what they see others doing?

- the older and infant gets, the more they are able to use info picked up from observing others' actions to create new, orginal actions - randomly assigned 18 month olds were placed into one of three groups - each group was shown 5 toys - children in successful demo group watched adult play w/ each toy, and adult modelled five target actions: pulling apart a barbell, placing stick in opening of a box, hanging a nylon loop on a peg, placing beads inside a jar, and placing a square cutout over a post - children in unsuccessful demo group watched adult attempt but fail these tasks, adult's hand slipped off barbell, or dropped the loop next to the peg, etc. - in the control group, children didn't observe any demo, they were just given the toys - Meltzoff looked at how often the children one ach group completed target activities - children in control group completed 24%, children in successful interaction group completed actions 78% of the time - children in unsuccessful group didn't imitate unsuccessful actions, but performed target actions as often as those in the successful group - they did the activities w/o ever observing the adult complete these actions, so children didn't imitate what they saw, but the actions they thought the adult was trying to complete CONCLUSION: older the child is, the more they go beyond rote imitation, and take into account the other things they are observing, what they see and what they have learned about the world

Do humans have mirror neurons?

- there is a suggestion that our brains have mirror neurons - researchers using electrodes to record brain activity in people w/ epilepsy in order to determine which part of their brains was generating seizures have recorded activity from neurons w/ the same properties as those ID'd in monkeys - fMRI in neuro normal individuals have further suggested these neurons are distributed throughout the frontal, parietal, and temporal lobes in a network called the mirror neuron system - need more research to determine if and how this system supports perception and action in humans

Describe Macguire's work on wayfinding practice on the brain?

- two groups of subj studied -> london Bus drivers who have learned specific routes - London taxi drivers, who travel to different parts of the city - bus and taxi drivers asked to ID pics of london landmarks - taxiers scores higher than bus drivers, which is what we'd expect from their greater exposure to all of London - when their brains were scanned, taxi drivers' hippocampus was larger - result similar to experience dependent plasiticity!!! Taxi drivers who have had extenisve experience navigating have larger hippocampus, and drivers w/ largest hippocampi were the ones with the most years of experience - strong support for experience dependent plasticity, and rulse out the possibility that ppl w/ larger hippocampi are just, more likely to be taxi drivers

Give an example about how gymnasts use self-produced info to create a backflip, and what else is needed?

- vision seems to be important! - say gymnasts wants to do a backflip - within 600ms, they have to execute flip and end in exact, correct body configuration precisely at the moment they hit the ground - they could learn to run a predetermined sequence of motions within a specific time -> but thats not what happens, Bardy and Laurent made expert gymnasts do open eye backflips and closed eye backflips they performed somersaults worse w/ closed eyes than open eyes - therefore, since it should be the same w/ open eyes or not if its a predetermined sequence, this is not the case - films showed that if eyes were open, gymnasts made in air corrections to trajectory - closing eyes did not affect performance of NOVICE somersaulters as much - experts apparently learn to coordinate movements w/ perceptions, a skill that novices have not yet learned - so loss of visual info for novices didn't really effect much - so, flipping involves using into created by movement to create further movement

What other information makes it so that optic flow isn't necessary for walking navigation?

- visual direction strategies -can navigate short distances w/o visual information at all bc of spatial updating

Mirror tracing game and gibson psychology

- visual information and feedback from body (proprioception) are working together - information from body and proprioceptive -> conflicting visual info from proprioception

What are the four important action and perception occurrences?

- walking or driving through environment - finding one's way from one location to another - reaching out and grasping objects - watching other people take action

Describe O'Keefe's rat experiments?

- wanted to find neural mechanisms that created these maps - used rats, and recorded individual neurons in hippocampus, which is important for memories - every time one of neurons fired, o keefe noted location of rat in the box - when these points were plotted along the rat's walking path, the individual neurons were found to fire when rat was in a specific place in the box, and different cells preferred different locations Description of findings - grey lines depict path taken by rat as it wandered - on top are the locations where four different (different coloured) neurons fired - purple neuron , for eg, only fired when animals was in upper right portion of box, and red only when it was in lower left - by ID neurons, O keefe saw activity of individual neurons in hippcampus code an animal's position in the environment - neurons now called place cells bc they only fire when animal is in a certain place in enviro - area of enviro the place cell fires is called place field

Describe the studies demoing that we can find our way even w/ limited optic flow info?

- we can find our way even when flow info is minimal (ie., at night) and so optic flow is not always necessary for navigation - Loomis eliminated optic flow altogether using a "blind walking" procedure where people observe a target object located up to 12 m away, then walk to target with eyes closed - people can walk directly toward target and stop w/in a fraction of a metre of it - people can do this even when they are asked to walk off in the wrong direction first and then make a turn and walk to the target, all while their eyes are closed - diagram shows that even when people walk to the left of the object, then are asked to turn at different points, and walk to the target 6 m away, they could and stopped close to target - shows that we can navigate short distances accurately in absence of any visual stimulation at all -can do this by mentally combining knowledge of own movements (muscle movements give walker sense of speed + shifts in direction), with their memory for position of the target through their walk - the way we and animals keep track of position in a surrounding environment = spatial updating - just bc we can walk towards objects w/o optic flow doesn't mean that we don't use the info = studies show flow provides important info about direction and speed when walking, which can be combined w/ visual directions strategy + spatial updating to guide walking behaviours

Describe how optic flow answers the Gibson psyc question "what is the information, what movement generates what movement? How is that structured and used?"

-- optic flow answer: info will let u navigate environment, and there's lots of ways info can be moved --- can use it to know where your destination is if you continue to move in the way you are moving --- as you move, there's some point where expansion is minimal or negligent --- perceiving brain of organism can navigate environment w/o knowing exactly what enviro is made of/high fidelity representations. It doesn't need this, bc all it needs is to focus on expansion, will always locate destination of movement - there will still be points with minimal expansion, even if you don't have a final final goal -> no matter what's happening, there will be a point w/ minimal expansion - KEY: info is structured by our movements, and gibsons want to know what causes that info

What are the results of experiments demoing relationship between ability to act and perception consistent with?

-consistent with JJ gibson's idea of affordances - Affordances are an object's possibility for action - perception of a particular object is determined both by what object looks like and way we interact w/ it -Gibson believes that perceiving is an achievement of the individual, not in appearance in the theatre of his consciousness - it is a keeping in touch w/ the world, and experience of things, not just a having of experiences - thus, many years later, researchers embrace the idea that perception is not just an appearance int eh theatre of consciousness, but the first step towards taking action in the environment t - some researchers have even suggested that action, or the potential for action, affects perception

What is the traditional approach to perception? What is the action based account?

-purpose of perception is to create representation in the mind of whatever is around us - focus on how enviro is repped in ns and in perceiver's mind - your perception of the world is representing what is "out there" and so accomplishes purpose of repping the environment -Action - purpose of vision =/- creating rep of what is out there, it is to guide our actions - makes sense when considering action is important for survival (ie., monkey grabbing fruit -> colour perceptors let it see the colour, which is crucial bc it knows food is present, but reaching for it is just important. Can't survive on visual information alone!)

L Describe the PRR

-scientists can record from single cells in this region and based on how they respond, learn about what they are repping - in parietal lobe, cells will encode particular grips that support reaching and grasping actions - eg of it is the experimental set up from text: dark room, looks at light, light comes on and there's an object, light goes off, but animal has to grab the thing - we do this when we reach for things in the night! based on your idea/knowledge that something is there, you can form the correct idea that something is there - cells prefer particular grip types - traces for neurons firing across time demonstrates a cell that prefers in response to a "ducky" hand shape (like grabbing a thin book) - however, cell doesn't fire and encode as intensely for the different hand actions - other cells prefer other grasps - all cells are in the PRR - higher level perceptual coding of affordance - encoding opportunities for action in the particular environment the animal is in - are these perceptual cells that respond to visual info, like V1, or motor cells? - answer = both, or neither - distinctions between these processes break down - animal is perceiving types of actions that can be performed out in the world

Describe Doerfeld and coworkers study on difficulty of carrying out an activity>

0 subjects est. weight of a basket of golf balls before and after lifting it two conditions: 1. solo, wehere subject expected they would be lifting basket alone 2. joint, where subject expected that he or she would lift basket w/ another person - actual weight = 20 pounds - before lifting basket, the subj est basket weight 21 pounds if they had to lift it alone, and 17.5 pounds if they thought they'd have help - after lifting, avg guess was 20 pounds in both conditions - so, anticipation of how difficult task will be influences perception of the properties of an object

Describe the two characteristics of optic flow?

1. Optic flow is more rapid near the moving observer -- the different speed of flow, fast near observer and slower farther away = gradient of flow - gradient provides info about how fast observer is moving - gibson says the observer uses the info provided by this gradient to determine their speed of movement 2. no flow at the destination towards which the observer is moving (focus of expansion ) - indicates where car will end up if its course isn't changed

L Descrive what mirror neurons do?

= cells don't respond when different actions are performed - encode execution and observation of a particular action, defined by how the body is moving - points to idea that cell is encoding something about action particularly - most of the research on these cells is done in monkäes - in humans, there is support that there are mirror neuron systems - purple = sensitive to reaching movements, orange area in the middle = tool use, lil green area = general movements, blue = upper limb movements - research is ongoing -> even in humans, there are distributed regions encoding different aspects of movement - mirror neurons are not just coding the sight of particular types of movements, execution of particular movement AND auditory consequences of movement as well!! (like ripping something apart, or when they just hear someone doing that) -

Describe DF and the ventral dorsal stream w/ action L

DF = person who could reach out and act just fine, but not perceive - gives us new insight to how special our abilities are - picking up coffee cup - perceptual senses needed is elaborate -> can think about what is happening - need ventral processes to allow us to ID cup, and the ability is different from being able to reach out and grasp the cup - you can also lose the ability on grasping objects - dorsal stream can be damaged so grasping becomes inhibited - this action is a core of human behaviour

Describe the ecological psychology and the information movement creates?

MOVING IN PARTICULAR WAYS GENERATE INFORMATION -> BY MOVING, WE CAN ACCESS STRUCTURED INFO AND USE IT TO GUIDE PERCEPTION - within these subdisciplines, there are schools of thought -> even in perception, it isn't just one block of people! - when talking about perception as being active, we owe a lot to JJ Gibson, who created a school of thought in perceptual psychology - huge focus on solving perception problems from bottom up, and confronting in a bottom up way - inverse projection problem -> info on retina can be formed by infinite configurations of objects - Gibson alerted ideas that perception is active -> so called Gibsonian psychology, or ecological psych - does not mean enviro psyc, but that perception happens out in the world, and perception happens as we engage with the world and environment - eco psychologists rejected idea that perception is passive, but we should think of it as the relationship of agent (us) interacting w/ environment - ie., the rocks that we perceived as a circle - by moving, we are generating new opportunities for perception + for us to perceive - Gibsonian/eco psychologists hone in and formalize idea that movign gives us dif. perspectives, interested in characterizing what type of info movement generates for us - yes there is light that counts as sound, but Gibson's insight was that, by moving, we generate sources of info that are given to us bc of the movement, and info is structured/consistent

Define topographical agnosia

a condition associated with brain damage in which patients are unable to recognize landmarks in real world environments

Define cognitive map

a mental map of the spatial layout of an area of the environment

Define parietal reach region

a network of areas in the parietal cortex that contains neurons involved in reaching behaviour

Define visuomotor grip cells

a neuron that initially responds when a specific object is seen and then also responds as a hand grasps the same objects

Define visual direction strategy

a strategy used by moving observers to reach a destination by keeping their body oriented towards the target

L Why is it hard to fly in a snowstorm?

different sources of motion and flow info in snowstorms there

Describe the visual motor grip cells? L

fire for particular objects, and just for the sight of particular objects not like cells that code for particular shapes, but code for grip of objects, and just the presence of an object the animal can act on

Define self produced info

generally, enviro info that is produced by actions of the observer ex. is optic flow, which occurs as a result of a person's movement and which, in turn, provides info that can be used to guide that movement

Define action specific perception hypothesis

hypothesis that people perceive their environment in terms of their ability to act on it

Define spatial updating

process by which people and animals keep track of their position in a surrounding environment when they move

Define optic flow

the flow of stimuli in the enviro that occurs when an observer moves relative to the enviro forward movement causes an expanding optic flow, whereas backward movement causes a contracting optic flow some researchers use the term optic flow field to refer to this flow

Define affordances

the info specified by a stim pattern that indicates how the stim can be used an example of an affordance would be seeing a chair as something to sit on, or a flight of stairs as something to climb

Define focus of expansion

the point in which flow pattern caused by observer movement in which there is no expansion according to JJ Gibson, the focus of expansion always remains centered on observer's destination

Define way finding

the process of navigating through the enviro wayfinding involves perceiving objects in environment, remembering objects and their relation to the overall scene, and knowing when to turn and in what direction

Define eco approach to perception

this approach focuses on specifying the info in the environment that is used for perception, emphasizing the study of moving observers to determine how their movement results in perceptual info that both creates perception and guides further movement


Kaugnay na mga set ng pag-aaral

Chapter 15 - The Lymphatic System

View Set

(Practice) Ch. 14 - Escrow and Title Insurance

View Set

Introduction to Exercise & Wellness Mid-Term Exam

View Set

Nutrition Final study guide - Chittom @ ICC

View Set