perceptual development

Question 1

what is sensation?

Answer 1

Sensation = refers to processing basic info from the environment by sensory receptors and brain

Question 2

what is perception?

Answer 2

Perception = organising sensory info into a coherent understanding of the world

Question 3

what did early research demonstrate about perception in infants? (1)

Answer 3

• through measuring how long children looked at visual stimuli, it was found that children had a visual preference (stared at longer) for faces

Question 4

what are the 2 key things modern research measure when exploring child perception?

Answer 4

o PREDERENTIAL-LOOKING – showing infants two stimuli to see if infants have a preference for one over the other
o HABITUATION – repeatedly presenting stimuli to an infant until the response declines. If infants are then shown a novel stimulus they de-habituate and researchers infers infants’ changed response to the stimuli

Question 5

vision: what is visual acuity? how is it measured in infants?

Answer 5

sharpness of visual discrimination
- an infant’s visual acuity can be estimated by comparing how long babies look at certain similar stimuli

Question 6

vision: how does a child’s visual acuity develop over childhood? (2)

Answer 6

• low in newborns
• sharpness of infants’ visual info develops so rapidly that is approaches that of an adults by age 8 months and reaches full adult by 6y/o

Question 7

vision: what is contrast sensitivity?

Answer 7

Contrast sensitivity = ability to sense light to dark contrast

Question 8

vision: how does contrast sensitivity develop over childhood? (2)

Answer 8

• up to 2 months prefer to look at patterns/colours of high visual contrast - poor contrast sensitivity (the ability to detect differences in light and dark areas) means high contrast is easier to percieve
• newborns’ cones are different size and shape and further apart than adults meaning colour is hard to detect at first

Question 9

vision: what is the difference between ‘cones’ and ‘rods’ in the eye?

Answer 9

cones - detect colour of the eye are concentrated in the fovea (central part of retina)
rods - detect light and dark

Question 10

vision: how does scanning develop over childhood? (2)

Answer 10

• 1 month old – scan the perimeter of shapes
• 2 month old – scan perimeter and interior of shape (Maurer & Salapatek, 1976)

Question 11

vision: how does tracking develop over childhood? (1)

Answer 11

• whilst infants begin ‘scanning’ immediately, smoother eye movement can’t track until about 2-3 months (Aslin, 1981)

Question 12

vision: why is it suggested that infants have a preference to look at faces? (2)

Answer 12

• evolutionary behaviour
• babies don’t prefer faces, it’s the pattern of the elements and intensity of contrast which resembles the structure of a face

Question 13

vision: when do children begin to understand the significance of different facial expressions?

Answer 13

4-5months

Question 14

vision: research into the ‘developing face expertise’

Answer 14

by 3 months infants prefer female faces, unless primary caregiver is male (Quinn et al 2002) – role of expertise/practice in face recognition

Question 15

vision: research into how attactiveness impacts an infants’ visual behaviour

Answer 15

• Langlois et al., 1990 - infants react more positively with people with attractive faces
• 12 month old children
• Very attractive/unattractive woman (same woman – different mask/makeup)
• Play with child
• child more responsive to attractive woman

Question 16

vision: how does pattern perception develop over childhood?

Answer 16

• 2 month olds can analyse and detect patterns in images
• seven month olds can detect the overall pattern of the ‘subjective contour’ test and also detect illusory square

Question 17

vision: what is perceptual constancy?

Answer 17

• Perceptual constancy = objects as being of constant size, shape, colour, etc., in spite of physical differences in the retinal image of the object – e.g if an object moves closer to you, the size of the retinal image perceived gets bigger but you know that it doesn’t actually get bigger

Question 18

vision: what does research suggest about infants’ perceptual constancy?

Answer 18

• Slater et al research suggested that children had an innate ability for perceptual constancy (dishabituated to the one that looked the same but was twice as big and far away

Question 19

vision: what’s object segregation?

Answer 19

object segregation - a child’s ability to perceive and understand two separate objects and the relationship between them
they also learn this through understanding gravity/functions of common movement

Question 20

vision: what is optical expansion?

Answer 20

optical expansion = depth cue in which an object gets closer and closer to you, highlighting that the object is coming towards you

Question 21

vision: what is stereopsis?

Answer 21

stereopsis - the perception of depth produced by the reception in the brain of visual stimuli from both eyes in combination; binocular vision

Question 22

vision: how does depth perception develop over childhood? (3)

Answer 22

• 1 month - respond to optical expansion (blink defensively at an object moving towards them)
• 4 months - stereopsis
• 6-7 months - rely less on binocular disparity, can perceive perceptual cues of depth through one eye alone

Question 23

vision: research into depth perception

Answer 23

AMES WINDOW research - at 7 months despite wearing an eye patch child reaches for the longer side of the the window – suggesting that depth perception is accessible through one eye alone

Question 24

vision: how do pictorial representations develop over childhood? (2)

Answer 24

• Struggle to distinguish the symbolic nature of 2D objects e.g child trying to eat an image of a cake
• Before 19 months, treat images as if they were real objects (DeLoache et al, 1998)

Question 25

hearing: how does auditory perception develop over childhood? (4)

Answer 25

• Adult levels by 5 or 6
• Newborns turn toward sounds, a phenomenon referred to as auditory localization
• Wertheimer (1961) – 10 mins old – children already showing signs of auditory localisation
• Clarkson & Clifton (1991) – Continuous sound is best

Question 26

hearing: how is perception of sounds measured in infants?

Answer 26

• Allow infant to suck on soother (dummy) that is connected to a computer and measure baseline sucking rate
• Present phoneme (/pa/) repeatedly
• Sucking rate first increases and then infant habituates (i.e., returns to baseline sucking rate) * Present new phoneme (/ba/)
• Infant dishabituates (i.e., sucking rate increases)

Question 27

hearing: what has research suggested about infants’ perception of music? (3)

Answer 27

• suggested that children have a biological predisposition to music
• infants respond to rhythm and temporal organisation in music, preferring music that had pauses between musical phrases rather than in the middle
• Infants are also sensitive to melody, showing habituation to the same tune (a particular sequence of notes)

Question 28

taste and smell: outline research which demonstrates infants having a preference for sweetness

Answer 28

• DESNOO RESERACH  treatment for mothers who had too much amniotic fluid – C1 inject dye and sweetner, C2 dye alone  more dye present in the urine of condition 1 than condition 2 – clear preference of sweetness

Question 29

taste and smell: how do infants’ sensitivity and smell develop over infancy? (3)

Answer 29

• develops before birth
• newborns (3-4 days) prefer the smell of breast milk, their natural food source
• 2 weeks - able to differentiate the scent of their own mothers from that of other women
• children and newborns’ facial expressions similar to adults reactions to tastes e.g sweet, sour etc

Question 30

touch: what is intermodal perception?

Answer 30

intermodal perception - the synching up of sight, sound etc cues together

Question 31

touch: how does intermodal perception develop over infancy? (1)

Answer 31

research found that by 5 months, infants can distinguish facial expressions and emotions in voices

Question 32

touch: outline the research into intermodal perception

Answer 32

• STERI AND SPELKE RESEARCH
  o Infants held two rings, one in each hand, under a cloth that prevented them from seeing the rings or their own bodies
  o For some infants the rings were connected by a rigid bar and therefore moved together * For others the rings were connected by a flexible cord and therefore moved independently
  o All the infants were allowed to hold and feel just one or the other type of rings until they had largely lost interest (habituated).
  o They were then shown both types of rings and looked longer at the rings that were different from those they had been exploring with their hands