Week 4 Flashcards

Question

How does the brain construct our percepts?

Answer 1

seeing is a construction in your visual system Optic nerve - point in the retina that is broken - interruption - where the optic nerve leaves the eye - brain is creating a plausible percept - dont see the hole Motion in old fashioned movies - still image after still image - perceive motion - brain creates the perception of motion The brain constructs percepts. Instinct blindness makes that process invisible to us.

Answer 2

Not for our pleasure - avoid dangerous and poisonous hazards Not to see the world as it really is Not to see the world accurately

Answer 3

Function is to allow us to behave sensibly in the world with respect to our survival and reproductive interests Make behavioral decisions that increase survival and reproduction Benefit from perceiving cues that inform decisions and behavior EX. larger animals hear lower frequency sounds (thumping a mile away) - smaller animals hear higher - likely to inform decisions about behaviors they engage in Hearing things that allow them to make decisions to benefit their survival and reproduction

Answer 4

Cost to build Cost to operate and process the info ----Benefit outweighs for it to be maintained by natural selection Fish with no eyeballs - lives in complete darkness - no benefit to building a visual system Evolution is sensitive to cost and benefits - no benefits after many generations

Answer 5

1 sensitive to wavelengths in only the range that the earths atmosphere lets through 2 That interacts via reflection and absorption with objects that are of interest to us- That reflects off of objects that are fitness relevant It is not that light just happens to be visible to us. Rather, we have named the part of the electromagnetic spectrum “light” that is visible to us, and it is visible to us because the function of our visual system is to allow us to interact with the world.

Answer 6

Disconnect between people’s ability to judge distance correctly when you ask them to report a distance and when you ask them to walk blindfolded - better when you walk than guess Action relevant perception -- People perceive the environment in terms of their own ability to act on it ---Softball players who hit better perceive the ball as larger - same with tennis and golf ---An object seems closer if one can reach it with a tool than if it is equally out of reach and no tool is available ---Judged a hill as steeper if they were tired - also if they were older or in poorer physical health

Answer 7

by our minds. Things are beautiful because our perceptual systems are designed to perceive them as beautiful -attraction to them increases our reproductive success. For example, flowers are beautiful to us, and flowers in a natural environment such as the EEAindicate the presence of a fertile, literally fruitful environment and portend the coming of a rich food source: fruit. Ex. face more interesting because it conveys info that may be important to our social decisions

Answer 8

. Whether one considers visual stimuli, auditory stimuli, or tactile stimuli, for example, there is a constant torrent of information and sensations that each developing organism is exposed to

Answer 9

infant needs to be able to orient to developmentally relevant (and not to superfluous) stimuli. Orienting devices are necessary to allow perceptual systems to attend to, select, and use developmentally relevant information. We call those orienting devices interests. Infants prefer to look at relevant stimuli, and social stimuli, such as faces are among the most important things they can look

Answer 10

1-month-old spent more time looking at the outline of the face while a 2-month-old looked more at the internal details of the face At 6 months of age, infants begin to look in the direction of an adult’s eye gaze if they can see both the adult’s eyes and head turning and if the object of interest is already within their visual field

Answer 11

Measure an observer’s direction of gaze - infer what in the visual scene that observer is looking at Early attempts - research watching observer Modern eye tracking - reflecting light off the cornea and recording the reflection of that light - infrared light doesn’t interfere because we cant see Calibration - look at 3 known points - records the pattern of reflected infrared light while the observer looks at those known points Adds temporal and spatial precision to the preferential looking paradigm, violation of expectation and habituation

Answer 12

Altricial - Least developed at birth - not a lot of visual sensation in utero Undefined lightness during day - complete darkness at night Responds to sudden change in light by 28 W No acuity or contrast

Answer 13

HEARING In order for prenatal hearing 1. Auditory system would have to be sufficiently developed 2. Have to be sounds that could travel through the mother’s tissues and arrive at the fetus’s auditory system -----Sounds pass into utero clearly - microphone into uterus Hear moms voice Hear other peoples voices Moms heartbeat and digestive system DeCasper and Fifer - operant conditioning 1. Measure how long they pause between sucking - take baseline - train to increase or decrease pause by rewarding them with another womans voice Heard and learned mothers voice before they were born - Motivated to hear mothers voices more than the voice of an unknown woman - recognized voice Later tested whether auditory experiences pre birth could affect preferences after birth ------7th month - Gave mothers who were seven months pregnant a story to read out loud twice per day until the baby was born ------Newborns preferred to hear the story that was read in utero - prefer familiar story even if read by stranger Study underlies that there is always an environment - does not just start at birth

Answer 14

Change in auditory perception with age 18 - gradually lose ability to hear highest pitches - decreases at a predictable rate - eventually making speech perception difficult Changes in the cochlea - tiny hair cells - hair cells and nerve cells are lost - connections between hair and nerve cells are lost

Answer 15

Develops early - first responds to touch near lips at 8w gest and touch elsewhere except the back of head at 16w gest Can touch things in utero and feel - grasp umbilical cord and suck thumb

Answer 16

Fetus has taste - swallow fluid that carries flavors and tastes recently eaten Preference for garlic if mother ate it during pregnancy Preference for sweetness - baby drinks more fluid - reduce amniotic fluid to reduce pressure in sac Mothers drink carrot juice - preference for it in infancy - measured how much carrot juice

Answer 17

Amniotic fluid will smell like the foods that the mother has just eaten - comes into contact with odor receptors Smell receptors are washed with amniotic fluid

Answer 18

1. Occipital cortex still developing after birth - muscles that allow lens to focus havent developed 2. Fovea - not fully populated with photoreceptors 3. Cells in visual cortex haven't myelinated and have not specialized to the type of visual stimuli they will be most responsive to in adulthood 4. Eye Movements are immature - slow and inaccurate

Answer 19

orient to larger shapes over smaller shapes, because he can see them as distinct Newborn has acuity of 20/600 - can see 20 ft what a normal adult can see at 600ft Lens is inflexible - cant change focus - objects in focus are 20 cm from eye experimenter stands behind a wall and watches the infant as the infant is presented with two side-by-side cards. One card shows black and white bars (either horizontal or vertical) and the other is solid grey Preference for one of the cards?

Answer 20

Newborns can see black and white but colour is not well developed Babies prefer to look at coloured objects - can only discriminate between green red white but not other colours 4m - mostly adult like Color vision involves three different kinds of photoreceptors or cones that mature at different rates 4m prefers to look at saturated colours Colour vision continues to develop into early childhood Colours that humans see are those that would have benefited our ancestors most in their search for berries among green

Answer 21

Visual cliff paradigm - large boxlike apparatus - top of the box was see through glass - red and white checker boards at different depths ----6m-14m babies hesitated when they reached the dividing line - perceived the difference in depth ----Hesitation associated with experience with self-propelled locomotion - walking or crawling - more likely to hesitate at the deep side and show evidence of depth perception ----Heart rate increases on deep side ----Visual exploration necessary for development of depth perception

Answer 22

Newborns can detect motion and track a moving object with their eyes 2-3m that an infant can smoothly move eyes in order to track a moving object 2-5 orient toward the moving object in an otherwise static visual field 3m - infant can use motion info to discriminate btw a display showing human shaped point light walker and group of lights Can anticipate trajectory

Answer 23

Auditory system is fairly well developed from birth Newborn can hear a variety of sounds and prefers to listen to human voices over pure tones Not as sensitive as adults - not able to hear low Can discriminate human speech

Answer 24

Most well-developed at birth - especially around mouth, palms of hands and soles of feet ---Early reflexes - responses to touch Stroke cheek near mouth - turn towards Finger - leads to sucking Finger in hand - grasp Babinski reflex - sole of foot - fan toes and twist foot Respond to temperature and can feel pain

Answer 25

Prefer sweet tasting liquid over water - relax facial muscles and show adult-like facial expression in response to sour and to bitter tastes Neutral to salty - like by 4m Ready to eat solids at 6m

Answer 26

Interested in faces over other images Size constancy Slow and inaccurate eye movements Lightness perception well developed Can discriminate red and green but not more subtle colors Can detect motion Startle response to unexpected noise Prefers hearing mother’s voice over that of a stranger’s Prefers hearing a story they heard before birth over a different story Hears high-pitched sounds better than adults; low-pitched sounds worse than adults Likes sweet tastes Can discriminate smells; prefers human milk; likes the smell of bananas and chocolate Sense of touch well developed, especially around mouth, palms of hands, and bottoms of feet

Answer 27

Looks mostly at the outline of faces Early evidence of depth perception

Answer 28

Ocular dominance columns have developed Can see a variety of bright colors (blue, red, green, yellow) Shape constancy Looks mostly at the internal detail of faces Brightness constancy (as long as the object is not too small)

Answer 29

Can see biological motion in a point-light walker Muscles needed to focus (by changing lens shape) are well developed Can track a moving object smoothly and accurately

Answer 30

Adult-like color vision Can discriminate more or less between saturated and unsaturated colors Color constancy

Answer 31

Visual acuity of 20/40 (can see at 20 feet what a normal adult can see at 40 feet) Consistently turns head toward direction of sound Just as good at discriminating between two people’s faces and two monkey’s faces

Answer 32

Now specialize in human faces, discriminating between people more easily than monkeys

Answer 33

Adult-like acuity

Answer 34

Functions from birth and can discriminate Relax in response to banana or chocolate - frown to rotten eggs and turn head Prefer smell of human milk over any other including amniotic 4days - prefer mothers milk over strangers, smell of a lactating woman over formula Prefer mothers smell in general over other women

Answer 35

The integration of percepts acquired via two or more modalities, or senses. Babies turn head to sound because they expect to see object Suck on pacifier - shown too - look longer at one they were sucking on - 1m and in new borns

Answer 36

PIAGET Rejected this idea - thought info would be separate for first few months after birth Difficult to explain from an associationist perspective -. Associationists would predict that once you have seen a pacifier you should be able to recognize it the next time you see it but not when you feel it.

Answer 37

The perception of like objects as like (in terms of size, color, lightness, and brightness) despite radically different projections on the retina Although constancies are functional, they are actually a failure of accurate perception - happens by design

Answer 38

size constancy allows our visual system to see an object as the same size despite being viewed at radically different distances and thus casting wildly different proximal images on the retina Slater - evidence for size constancy - habituation - two cubes - one double in size - See only small at various distances Test phase - two side by side - larger far away - look longer at new box despite the same size projection on the retina

Answer 39

looking at an ice cream cone straight on. Now imagine moving your head up (or the cone down) so that you see mostly a ball of ice cream with a little crescent of cone visible at the bottom. The image projected on the retina is radically different, but you have no problem still seeing the object as an ice cream cone and as the same shape. Bower- 2m - conditioned to turn head to one stimulus that was presented repeatedly - new stimulus that may vary in orientation, distance, size or retinal size - turned their heads if same as original suggesting constancy

Answer 40

The visual system isn’t designed to see the world as it is The visual system is designed to create representations that inform behavioral decisions

Answer 41

Perceive object at same brightness across illuminations Show at 7 weeks

Answer 42

Colour is a perception Colour is not determined by wavelength Color constancy develops later than brightness constancy.

Answer 43

dedicated to face perception FFA Specialized for face processing - sometimes be used for processing other objects - may be used sometimes for processing other objects that are special areas of expertise for certain individuals

Answer 44

the disruption in face processing that is observed when a face is viewed upside down Which two pictures is identical to a third - if pictures inverted - slower to choose and less accurate Cost of inversion is higher if the pictures are of faces - 10% less accurate with cars, houses, furniture but 25% less accurate if the pictures are of faces evidence that faces are processed differently than other objects and that the perceptual mechanisms that process faces are so specialized that they do not work when face images are inverted.

Answer 45

The integration of visual information from the whole of the perceived visual region of interest, usually the face region, in contrast to the perception and representation of component parts. Composite face task

Answer 46

participants are asked to tell whether the upper half of a face is the same in two images that show the upper half of faces aligned with different bottom halves - brain is integrating top and bottom half Can differentiate when misaligned If the two top halves are identical, people find it very difficult to see that they are the same because they see each face as a whole, and the difference in bottom halves makes the two faces seem different Holistic processing as early as 6yrs

Answer 47

2m (1981) prefer to look at faces - cartoon like faces scrambled Measure how long looking at a face isolated

Answer 48

9min old infants - how far willing to turn their eyes and their heads farther to keep a schematic face in view than to see a scrambled or blank stimulus People had believed that infants learned based on experience - conflicting evidence Results were replicated 16 yrs later - infants show competence, lose it and show again - u shaped curve

Answer 49

Replicated Goren, Sarty and Wu, U shaped curve Johnson and Morton proposed a two-process development plan wherein an early system orients the baby to things in the environment that are likely to be faces, and the second process takes advantage of this visual orientation to build its adult-like face template that will be used for face recognition throughout life.

Answer 50

Single cell recordings - electrodes in a single cell - cat is looking at line at a particular slant Cells respond to certain orientations Ocular Dominance columns - column of neurons in the visual system that all respond to input from either the right or left eye Within a particular column - one eye is dominant Newborn cats do not have ocular dominance columns, evidence at 1m developed by 2m - Do not exist in newborns - cells respond to info in both eyes

Answer 51

If the kitten was deprived of input from one eye, the entire visual system would become devoted to processing information from the other eye. The columns that would otherwise have been devoted to, say, the left eye, would come to receive and process information from the right eye. And this switchover is irreversible. If the developing kitten received no input from the left eye during the critical period, it would lose the ability to respond normally to input from that eye.

Answer 52

developmental process that relies on experience by capitalizing on dependable environmental regularities At birth sew one of the eyes shut - without experience in one eye - ocular dominance column would not develop Open closed eye - no ocular dominance columns - critical period for development of the columns No one realized that visual experience was necessary for the development of ocular dominance columns

Answer 53

ONE Manipulating the environmental input by depriving visual input from one eye permanently changes the visual system Nature and nurture question is wrong - working together want to know how the psychological process was designed to develop in the species- typical environment TWO Critical periods - needed to be visual input into each eye at a critical time in development or the normal development of the visual system would never be possible - evo by ns selected for critical periods because they are an efficient method for building an adult organism

Answer 54

A developmental process in which perceptual mechanisms become more specialized such that infants lose the ability to discriminate between categories that are irrelevant. 6m are better at 9m at discriminating between 2 monkey faces and human faces 9m - good at human faces but not monkey faces Perceptual narrowing in face processing after only being exposed to a subset of faces - if only exposed to monkey faces could go the other way - japanese monkeys

Answer 55

Unable to see depth in 2d paintings - unable to solve necker cube Could read from a clock Report distance between objects in room Unable to perceive faces Was a skilled machinist but was unable to recognize tools he used before by sight

Answer 56

A situation in which two or more groups exist through no action of the experimenter, allowing a comparison between these naturally occurring groups Ex. cataracts

Answer 57

Existence of cataracts in children - Maurer - young children who were born with bilateral cataracts that were so dense they completely blocked visual access in the center of the visual field Early visual deprivation from cataracts had an effect on the development of face perception Tested group who had been treated for congenital cataracts - complete early visual deprivation - compared to control - previsously deprived group were worse in facial recognition tasks