Chapter 4: Infancy: Early learning, motor skills, and perceptual capacities Flashcards
1
Q
True/False:
Babies start relating to their social worlds from around six weeks.
A
False. In relating to their social worlds, babies are active from the start.
2
Q
Define reflex
A
an inborn, automatic response to a particular form of stimulation
3
Q
What stimulation is required to induce the eye blink reflex?
A
By shining a bright light at the eyes or clapping near the head
4
Q
What is the eye blink reflex?
A
Infant quickly closes eyelids
5
Q
True/False:
The eye blink reflex disappears at 3 months.
A
False. It is a permanent reflex.
6
Q
What is the function of the eye blink reflex?
A
It protects the infant from strong stimulation
7
Q
When an infant’s cheek is stroked near the corner of the mouth, the infant turns his/her head towards the source of stimulation. What is this reflex called, and what is the function of this reflex?
A
Rooting. It helps the infant find the nipple.
8
Q
When does the rooting reflex disappear?
A
At around 3 weeks when it becomes voluntary head turning
9
Q
What stimulation induces the sucking reflex?
A
Placing a finger in the infant’s mouth induces the sucking reflex, and an infant will suck rhythmically on the finger
10
Q
True/False:
The sucking reflex disappears at around 4 months.
A
True. The sucking reflex is replaced by voluntary sucking after 4 months
11
Q
What is the function of the sucking reflex?
A
It permits feeding
12
Q
The swimming reflex occurs when an infant is face down in pool of water. What does the infant do in response?
A
The infant paddles and kicks in swimming motion
13
Q
True/False:
The swimming reflex disappears around the age of 8 months.
A
False. The swimming reflex disappears earlier - around 4-6 months.
14
Q
What is the function of the swimming reflex?
A
It helps the infant survive if dropped into water
15
Q
What stimulation induces the moro reflex?
A
The infant is held horizontally on its back and its head is allowed to drop slightly, or a sudden loud sound against the surface supporting infant is produced.
16
Q
What is the moro reflex?
A
In response to the stimulus, the infant makes an ‘embracing’ motion by arching its back, extending its legs, throwing its arms outward, and then bringing its arms in toward the body
17
Q
What is thought to be the function of the moro reflex?
A
In human evolutionary past, the moro reflex may have helped the infant cling to its mother
18
Q
When does the moro reflex disappear?
A
At approximately 6 months.
19
Q
When a finger is placed in an infant’s hand and pressed against the infant’s palm, the infant spontaneously grasps the finger. What is this reflex called?
A
Palmar grasp
20
Q
When does the palmar grasp reflex disappear?
A
Around the age of 3-4 months.
21
Q
What purpose is served by the palmar grasp reflex?
A
It prepares the infant for voluntary grasping
22
Q
What stimulation is required to induce the tonic neck reflex?
A
While the infant is lying awake on its back, its head is turned to one side.
23
Q
The infant lies in ‘fencing position’ with one arm is extended in front of the eyes on the side to which the head is turned, while the other arm is flexed. Which reflex is this?
A
Tonic neck
24
Q
When does the tonic neck reflex disappear?
A
Around 4 months.
25
What is the function of the tonic neck reflex?
It may prepare the infant for voluntary reaching
26
How is the stepping reflex stimulated, and what is the infant's response?
The infant is held under the arms, and its bare feet are allowed to touch a flat surface. In response, the infant lifts one foot after another in a stepping motion.
27
True/False:
| The rate of weight gain in an infant affects the time that the stepping reflex disappears.
True. The stepping reflex disappears at around 2 months in infants who gain weight quickly, but it is sustained in lighter infants
28
Which reflex is thought to prepare the infant for walking?
The stepping reflex
29
When an infant's sole of a foot is stroked from the toes towards the heel, the toes fan out and curl as the foot twists. Which reflex is this?
Babinski reflex
30
When does the babinski reflex disappear?
Between 8 - 12 months
31
What function does the babinski reflex serve?
This function is unknown
32
What are the five functions of infant reflexes in general?
1. Some have survival value
2. Some probably helped babies survive during our evolutionary past
3. Some help parents and infants establish gratifying interaction
4. Some can also help parents comfort the baby because they permit infants to control distress and amount of stimulation
5. A few reflexes form the basis for complex motor skills that will develop later
33
Why is it important to assess reflexes?
Paediatricians test reflexes carefully because they can reveal the health of a baby’s nervous system.
34
What can weak or absent reflexes, overly rigid or exaggerated reflexes, and reflexes that persist beyond the point of development when they should normally disappear signal?
Brain damage
35
Are differences in reflexive responses enough to cause concern about possible brain damage?
No. An observer must assess reflexes along with other characteristics to distinguish normal from abnormal.
36
How many states of arousal do infants have?
5. These are: Regular, or NREM, sleep; Irregular, or REM, sleep; Drowsiness; Quiet alertness; Waking activity and crying
37
What does the term 'states of arousal' refer to?
degrees of sleep and wakefulness
38
Describe regular, or NREM, sleep.
The infant is at full rest and shows little or no body activity. The eyelids are closed, no eye movements occur, the face is relaxed, and breathing is slow and regular.
39
How much time do newborns spend in each state of arousal per day?
```
Regular, or NREM, sleep: 8-9 hours
Irregular, or REM, sleep: 8-9 hours
Drowsiness: varies
Quiet alertness: 2-3 hours
Waking activity and crying: 1-4 hours
```
40
What does irregular, or REM, sleep look like?
Gentle limb movements, occasional stirring, and facial grimacing occur. Although the eyelids are closed, occasional rapid eye movements can be seen beneath them. Breathing is irregular.
41
In the drowsiness state of arousal, what does the infant do?
The infant is either falling asleep or waking up. Body is less active than in irregular sleep but more active than in regular sleep. The eyes open and close; when open, they have a glazed look. Breathing is even but somewhat faster than in regular sleep.
42
The infant’s body is relatively inactive, with eyes open and attentive, and breathing is even. Which state of arousal is this infant in?
Quiet alertness
43
What occurs during waking activity?
The infant shows frequent bursts of uncoordinated body activity. Breathing is very irregular; face may be relaxed or tense and wrinkled. Crying may occur.
44
Why do babies sleep more at night?
The foetus tends to synchronise its periods of rest and activity with those of the mother prior to birth.
45
How changes occur in an infant's arousal patterns between birth and 2 years old?
The organisation of sleep and wakefulness changes substantially. Total sleep declines gradually, but periods of sleep and wakefulness become fewer but longer, and the sleep-wake pattern increasingly conforms to a circadian rhythm (24 hour schedule).
46
What three factors influence the changes in arousal patterns that occur in the first two years of life?
1. brain development
2. cultural beliefs and practices
3. individual parents’ needs
47
What implications do arousal patterns have for the cognitive development of infants?
Babies who spend more time quietly alert probably receive more social interaction and opportunities to explore, and may be slightly ahead in mental development.
48
Describe the two states of sleep.
1. Irregular, or rapid-eye movement (REM), sleep: brain wave activity measured with the EEG is remarkably similar to that of the waking state.
2. Regular, or non-rapid-eye movement (NREM), sleep: body is almost motionless, and heart rate, breathing, and brain-wave activity are slow and even.
49
How do infants' sleep patterns differ from children and adults?
Infants spend more time in REM sleep.
REM sleep is approximately 50% of a newborn baby’s sleep time. By 3 to 5 years, it has declined to an adult-like level of 20%.
50
Why do babies spend more time in the REM state?
Possibly to fulfil their need for stimulation which is not fulfilled by their short times of quiet alertness/wakefulness
51
The REM state safeguards the central nervous system. What is the other protective feature of REM sleep?
It also protects the health of the eye – eye movements cause vitreous to circulate, which delivers oxygen to parts of the eye that do not have their own blood supply.
52
What can be observed in the sleep cycles of infants who are brain damaged, or have experienced birth trauma?
Observations of sleep can help identify central nervous system abnormalities. Disturbed REM-NREM sleep cycles are often present in infants who are brain damaged, or have experienced birth trauma.
53
What is the most common cause of a young infant's cry?
Hunger
54
What effect does parental responsiveness to an infant crying have?
Ethological research indicates that parental responsiveness to infant crying leads to less crying over time.
55
How does crying ensure that babies get the care and protection that they need?
The sound of a baby crying stimulates feelings of discomfort in most adults, which is an innately programmed response.
56
When Western parents choose to practice __________, amount of crying in the early months is reduced by about one-third.
proximal care
57
How do the cries of brain-damaged infants, or those who have experienced birth trauma, differ from those of healthy infants?
They are often shrill, piercing, and shorter in duration than those of healthy infants.
58
What is the most widely used instrument for assessing the organised functioning of newborns?
T. Berry Brazelton’s Neonatal Behavioral Assessment Scale (NBAS)
59
What does the NBAS provide information about?
Individual and cultural differences in newborn behaviour by evaluating the baby’s reflexes, muscle tone, state changes, responsiveness to physical and social stimuli and other reactions
60
What does NNNS stand for?
The Neonatal Intensive Care Unit Network Neurobehavioural Scale (NNNS), which is a recently developed instrument consisting of items similar to the NBAS, but is specifically designed for use with newborns at risk for developmental problems because of low birth weight, preterm delivery, prenatal substance exposure, or other conditions
61
Define learning.
Changes in behaviour as the result of experience
62
True/False:
| Newborns have built-in learning capacities.
True. Newborns are capable of two basic forms of learning: classical and operant conditioning, and they also learn through their natural preference for novel stimulation and through observing others.
63
What makes classical conditioning possible in newborns?
Newborns' reflexes.
64
What is classical conditioning?
A neutral stimulus is paired with a stimulus that leads to a reflexive response.
65
What must occur before learning can take place through classical conditioning?
Before learning takes place, an unconditioned stimulus (UCS) must consistently produce a reflexive, or unconditioned response (UCR).
66
How does learning take place in classical conditioning?
To produce learning, a neutral stimulus that does not lead to the reflex is presented just before, or at about the same time as, the UCS.
67
What happens when learning has occurred through classical conditioning?
The neutral stimulus alone produces a similar response to the reflexive response. The neutral stimulus is then called a conditioned stimulus (CS), and the response it elicits is called a conditioned response (CR).
68
In classical conditioning, what is extinction?
If the CS is presented alone enough times, without being paired with the UCS, the CR will no longer occur.
69
True/False:
| It is easy to classically condition most responses, including fear, in newborns.
False. Some responses, such as fear, are difficult to classically condition in young infants because, without the motor skills to escape unpleasant events, they have no biological need to form those associations.
70
Why are some responses easier to classically condition in newborns?
The association between two stimuli that have survival value are most easy to classically condition.
71
How do infants learn through operant conditioning?
Infants act, or operate, on the environment, and the stimuli that follow their behaviour change the probability that the behaviour will occur again.
72
With regards to operant conditioning, what is a reinforcer?
A stimulus that increases the occurrence of a response.
73
In operant conditioning, what is punishment?
Either removing a desirable stimulus or presenting an unpleasant one to decrease the occurrence of a response.
74
What important information has operant conditioning revealed about infants?
Operant conditioning has revealed important information about infant memory: 2 month olds remember for 1-2 days after training; by 6 months, memory increases to two weeks; at 18 months, memory was retained after 13 weeks.
75
What does this statement mean:
| Infant memory is highly context-dependent?
It needs to be the same task in the same situation. This decreases with age.
76
Define habituation.
A gradual reduction in the strength of a response due to repetitive stimulation.
77
Once habituation occurs, what can be done to cause the habituated response to return?
A new stimulus – a change in environment – causes the habituated response to return to a high level (recovery)
78
True/False:
After a baby has habituated to a particular stimuli, and then recovers to a new one, the baby is unable to distinguish the habituated stimuli and the recovered one.
False. A baby who first habituates to a visual pattern, then recovers to a new one, appears to remember the first stimulus and to perceive the second one as new and different from it.
79
Preterm and newborn babies have long habituation times. When does habituation occur more quickly?
By 4 or 5 months
80
Over time, infants shift from a novelty preference to a familiarity preference; that is, they recover to a familiar stimulus rather than to a novel stimulus. What does this shift allow researchers to use habituation for?
To assess remote memory
81
What are among the earliest available predictors of intelligence in childhood, adolescence, and young adulthood?
Habituation and recovery to visual stimuli - because they assess memory as well as quickness and flexibility of thinking, which underlie intelligent behaviour at all ages.
82
Which two forms of memory are referred to in the text?
1. Recognition: simplest form of memory
| 2. Recall: more challenging form of memory; remembering something not present.
83
Newborns are able to engage in recognition. By what age can infants engage in recall?
By the middle of the first year, infants can engage in recall.
84
Define imitation
Copying the behaviour of another person
85
Why do some researchers believe that imitative responses do not actually occur in newborns?
Because newborn mouth and tongue movements occur with increased frequency to almost any arousing stimulus, some researchers argue that certain newborn ‘imitative’ responses are actually mouthing. Imitation is also harder to induce in 2-3 month old babies than in newborns so sceptics believe that the newborn imitative capacity is little more than an automatic response that declines with age.
86
While some researchers claim that imitative responses in newborns are nothing more than mouthing, an automatic response that declines with age, what do other researchers claim?
Newborns imitate a variety of facial expressions and head movements with effort and determination when the adult is no longer demonstrating the behaviour. They argue that imitation does not decline.
87
What are mirror neurons?
Specialised cells in many areas of the cerebral cortex that underlie imitative capacities
88
What has been noted about the firing of mirror neurons when an infant hears/sees an action, and when it carries out the same action?
Mirror neurons fire identically when an infant hears or sees an action and when it carries out the same action.
89
By what age do infants have a functioning mirror neuron system?
Brain-imaging studies have found a functioning mirror neuron system as early as 6 months of age.
90
What are the two benefits of imitation in infants?
1. Desirable behaviours can be elicited through imitation
| 2. Reinforces the relationship between parent and child because of the pleasure it gives to caregivers.
91
What is gross-motor development?
Control over actions that help infants get around in the environment, such as crawling, standing, and walking
92
What is fine-motor development?
Control over smaller movements, such as grasping and reaching
93
True/False:
Motor skills are separate, innate abilities that emerge in a fixed sequence governed by a built-in maturational timetable.
False. This was the historical view which has long been discredited. Motor skills are interrelated. Each is the product of earlier motor attainments and a contributor to new ones. Children acquire motor skills in highly individual ways. Many influences join together to influence the transformations in motor competencies in the first two years.
94
The rate of motor progress shows large individual variability, but there are two trends common to all infants. Names these trends.
1. cephalocaudal trend (head-to-tail sequence)
| 2. proximodistal trend (from the centre of the body outward).
95
What is the average age and age range that 90% of infants achieve neck control (i.e. When held upright, head is held erect and steady)?
Average age: 6 weeks
| Age range: 3 weeks – 4 months
96
True/False:
| When prone, an infant can lift itself up using its arms by the age of 2 months.
True. The average at which infants achieve this is 2 months; however, this ranges between 3 weeks and 4 months.
97
What is the average age and age range when 90% of infants can roll from their side to their back?
Average age: 2 months
| Age range: 3 weeks - 5 months
98
When do are most infants able to grasp a cube?
Average age: 3 months 3 weeks
| Age range: 2 – 7 months
99
True/False:
| Infants start rolling from their back to their side at around 6 weeks.
False. the average age when infants achieve this skill is 4 ½ months, with 90% of infants achieving it between 2 and 7 months.
100
When are most infants able to sits without support?
Average age: 7 months
| Age range: 5 – 9 months
101
True/False:
| Most infants can crawl at 7 months.
True. The average age when infants start crawling is 7 months, with 90% of infants achieving this between 5 and 11 months.
102
When do infants pull themselves to standing position?
Average age: 8 months
| Age range: 5 – 12 months
103
A six month old infant plays pat-a-cake with his mum. Is this unusual?
Yes. The average age when infants achieve this skill is 9 months, 3 weeks, with 90% of infants achieving it between 7 and 15 months.
104
True/False:
| Most babies can stand by themselves by the time they are 12 months old.
True. The average age when babies stand without support is 11 months, with 90% of infants achieving this skills between 9 and 16 months
105
A 10 month old baby is able to walk on his own. Is this unusual?
No. While the average age that babies start walking is 11 months, 3 weeks, 90% of infants start walking between 9 and 17 months so a 10 month old who is able to walk falls within this range.
106
When are babies able to build a simple two-cube tower?
Average age: 11 months, 3 weeks
| Age range: 10 – 19 months
107
True/False:
| Most children are able to scribble vigorously between 10 and 21 months.
True. 90% of infants scribble vigorously between 10 and 21 months, with 14 months being the average age when babies are able to do this.
108
When can babies walk up stairs with help?
Average age: 16 months
| Age range: 12 – 23 months
109
When can children jump in place?
Average age: 23 months, 2 weeks
| Age range: 17 – 30 months
110
Shortly after starting to walk at 12 months, an infant starts walking on tiptoes. Is this unusual?
Yes. Most children are only able to walk on tiptoe at around 25 months, with 90% of children achieving this skill between 16 and 30 months old.
111
According to the dynamic systems theory of motor development, what does mastery of motor skills involve?
Mastery of motor skills involves acquiring increasingly complex systems of action. When motor skills work as a system, separate abilities blend together, each cooperating with others to produce more effective ways of exploring and controlling the environment.
112
According to the dynamic systems theory of motor development, what four factors jointly produce new skills?
1. Central nervous system development
2. Body’s movement capacities
3. Goals that the child has in mind
4. Environmental supports for the skill
A change in any of those elements makes the system less stable and the child starts to explore and select new, more effective motor patterns.
113
According to the dynamic systems theory, why is motor development not only genetically determined?
Motor development is motivated by exploration and the desire to master new tasks. Heredity can map motor development out at a general level: rather than being hardwired into the nervous system, behaviours are softly assembled, allowing for different paths to the same motor skill.
114
What type of studies do dynamic systems theorists conduct in order to discover how infants acquire motor skills?
Microgenetic studies, by following babies from their first attempts at a skill until it becomes smooth and effortless.
115
How do cultural variations impact on motor development?
Some cultures actively encourage motor development, while others discourage it which affects the rate of motor skill development.
116
Which fine motor skill plays the greatest role in infants' cognitive development?
Reaching
117
What is prereaching?
Poorly coordinated swipes made by newborns which drops out at around 7 weeks of age.
118
Why does prereaching drop out?
Due to babies improved control over eye movements involved in tracking and fixating on objects, which is essential for accurate reaching.
119
When does reaching reappear as purposeful, forward arm movements?
3 - 4 months, as infants develop the necessary eye, head, and shoulder control
120
Do babies need to use vision to guide the arms and hands in reaching?
No. By 5 -6 months, infants continue to reach for an object in a room that has been darkened (by switching off the lights) during the reach.
121
What is proprioception?
Our sense of movement and location in space, arising from stimuli within the body.
122
4 month olds aim their reach ______ of a moving object
ahead
123
When an object is moved beyond their reach, what do 5 month olds do?
Reduce their effort.
124
When do babies reach with one arm instead of both?
By 7 months, the arms become more independent and infants reach with one arm, instead of both.
125
Once infants can reach, they modify their _____
grasp
126
Describe the ulnar grasp.
A clumsy motion in which the baby’s fingers close against the palm
127
By the end of the first year, infants use the thumb and index finger in a well-coordinated grip. What is this grip called?
Pincer grip
128
When do infants begin to solve simple problems that involve reaching, such as finding a hidden toy?
8 - 11 months
129
Infants’ capacity to reach for and manipulate an object increases their attention to the way an adult reaches for and plays with that object, which broadens the infant’s understanding of others’ behaviours and of the range of possible actions. What type of neurons might be involved in this process?
Possibly mirror neurons.
130
What factors influence the development of reaching?
1. Early experiences
2. Cultural differences: In cultures where infants are given many opportunities to reach and grasp, they refine these skills earlier than in cultures where there are fewer opportunities.
3. Visual surroundings: optimal levels of stimulation encourage reaching and grasping; too much can cause a baby to cry and turn away from the stimulation discouraging reaching.
131
How do motor development and perceptual development influence each other?
Motor activity is a means for exploring and learning about the world, and improved perception brings about more effective motor activity
132
What are the two reasons why researchers are interested in to what young infants perceive with their senses, and how perception changes with age?:
1. Studies of infant perception reveal in what ways babies are biologically prepared to perceive their environment, and how brain development and experience expand their capacities.
2. Infant perception sheds light on other aspects of development – e.g. touch, vision, and hearing enable us to interact with others, so they are basic to social, emotional, and cognitive development.
133
What is the fundamental means of communication between parents and babies?
Touch
134
Which areas of the body are the first to become sensitive to touch during the prenatal period?
the mouth, palms, soles of feet, and genitals
135
How do we know that newborns are sensitive to pain?
They respond with a high-pitched, stressful cry, and increased heart rate, blood pressure, palm sweating, pupil dilation, and muscle tension, along with activation of sensorimotor areas of the cerebral cortex.
136
What two things can be used to relieve pain in newborns?
1. Sugar solutions
2. Certain anaesthetics
(particularly when coupled with gentle holding by the parent).
137
Research on infant mammals indicates that physical touch releases endorphins. What are endorphins?
Pain killing chemicals in the brain
138
Allowing a baby to endure severe pain overwhelms the nervous system. What does this impact?
It can disrupt the child’s developing capacity to handle common, everyday stressors, which results in:
1. Heightened pain sensitivity
2. Sleep disturbances
3. Feeding problems
4. Difficulty calming down when upset
139
How do we know newborns can distinguish between different tastes?
By their facial expressions: They relax their facial muscles in response to sweetness, purse their lips when the taste is sour, and show a distinct arch like mouth opening when it is bitter.
140
Why is a newborn's ability to distinguish between tastes important for survival?
The food that best supports an infant’s early growth is sweet-tasting breast milk.
141
At around 4 months, babies prefer a salty taste to plain water. Why?
This may prepare them to accept solid foods
142
True/False:
| A taste that is initially disliked by a baby can become a preferred taste.
True. A taste that was previously disliked can come to be preferred when it is paired with relief of hunger.
143
What influences a baby's early odour preferences?
During pregnancy, the amniotic fluid is rich in tastes and smells that vary with the mother’s diet and these influence the newborn’s early preferences.
144
How does an infant's responsiveness to sound help support their exploration of the environment?
By prompting them to turn their heads in the general direction of the sound
145
True/False:
Conduction of sound through structures of the ear and transmission of auditory information to the brain is efficient from birth
False. Conduction of sound through structures of the ear and transmission of auditory information to the brain is INEFFICIENT at birth
146
Infants with severe visual impairments are not motivated to move independently until _________ is achieved.
‘reaching on sound’
147
Which sounds do newborns prefer?
Complex sounds, such as noises and voices, to pure tones.
148
Can very young infants distinguish a variety of sound patterns?
Yes
149
By what age do babies show a sense of musical phrasing, preferring music with pauses between phrases to music with awkward breaks?
4 - 7 months
150
Young infants listen _____ to human speech than structurally similar non-speech sounds
longer
151
Why do adults generally use a slow, clear, high-pitched, expressive voice when talking to babies? And, what is the benefit of doing this?
Probably because they notice that infants are more attentive to this type of speech. This eases their perceptual learning
152
At around 5 months, what do ERP brain-wave recordings reveal about babies' speech perception?
They become sensitive to syllable stress patterns in their own language.
153
When do babies start screening out sounds not used in their native tongue?
Between 6 – 8 months
154
With regards to speech perception, what do babies start doing around 7 – 9 months?
They infants extend their sensitivity to speech structure to individual words, and begin to divide speech stream into individual words.
155
How does statistical learning capacity relate to analysing the speech stream?
by analysing the speech stream for patterns (repeatedly occurring sequences of sounds), babies acquire a stock of speech structures for which they will later learn meanings, long before they start to talk around age 12 months.
156
How does an infant's responsiveness to speech strengthen their language processing?
An infant's responsiveness to speech encourages parents to talk to them, and doing so strengthens infants’ language processing.
157
Which is the least developed sense at birth?
| Why?
Vision.
Visual structures in the eye and the brain are not yet fully formed: Cells in the retina are not as mature or densely packed as they will be in several months; optic nerve that relays these messages, and visual centres in the brain that receive them, will not be adult-like for several years; muscles of the lens are weak. As a result, visual acuity is limited.
158
What is the retina?
The membrane lining the inside of the eye that captures light and transforms it into messages that are sent to the brain
159
What is the function of the lens of the eye?
It permits adjustment of focus
160
Define visual acuity.
fineness of discrimination
161
Describe how an infant's vision develops (birth, 2 months, 4 months, 6 months, 4 years).
At birth: perceive an object at a distance of 20 feet as clearly as most adults do at 600 feet; images such as a parent’s face, even close up, look blurry, and despite a preference for coloured over grey stimuli, infants are not yet good at discriminating colours
Around 2 months: can focus on objects about as well as adults
Around 4 months: colour discrimination is adult-like.
By 6 months: visual acuity reaches 20/80
By 4 years, it reaches the adult level of 20/20
162
What is depth perception?
The ability to judge the distance of objects from one another and from ourselves
163
What piece of equipment was used in the earliest studies of depth perception?
The visual cliff, which consists of a plexiglass-covered table with a platform at the centre, a ‘shallow’ side with a checkerboard pattern just under the glass, and a ‘deep’ side with a checkerboard several feet below the glass.
164
List the three depth cues in the order in which sensitivity to them emerges.
Motion
Binocular depth cues
Pictorial depth cues
165
When do babies become sensitive to motion as a depth cue?
At 3-4 months, babies blink their eyes defensively when an object moves towards their face.
166
What is stereopsis?
Binocular depth cues arise because our eyes have slightly different views of the visual field. Stereopsis is the process in which the brain blends the two images.
167
When does sensitivity to binocular depth cues emerge?
Between 2 and 3 months, and improves rapidly over the first year.
168
At what age are babies aware that objects are 3-dimensional?
By the time they are 3 months old
169
What are pictorial depth cues?
Receding and overlapping lines and line junctions.
170
What does habituation research indicate about babies' sensitivity to pictorial depth cues?
3-4 month olds can discriminate between structurally possible and impossible drawings of a cube (they look much longer at the impossible image, as if puzzled by it). Pictorial sensitivity improves considerably between 5 and 7 months.
171
What is one possible reason for why sensitivity to depth cues emerges in the order that they do?
Motor development. Control of the head during the early weeks may help babies notice motion and binocular cues. Around 6 months, the ability to handle and feel the surface of objects may promote perception of pictorial cues as infants pick up information about size, texture, and shape.
172
Infants with more ________ experience (regardless of when they started) are more likely to refuse to cross the deep side of the visual cliff
crawling
173
Newborns prefer to look at _________ rather than _____ stimuli
patterned, plain
174
What explains early pattern preferences?
Contrast sensitivity.
Contrast refers to the difference in the amount of light between adjacent regions in a pattern. If babies are sensitive to the contrast in two or more patterns, they prefer the one with more contrast.
175
Describe the development of combining pattern elements (early weeks, 2-3 months, 4 months, 12 months)
Early weeks: infants respond to the separate parts of a pattern.
2 – 3 months: scanning ability and contrast sensitivity improves, so they explore the pattern’s internal features, pausing briefly to look at each salient part.
4 months: good at detecting patterns so they can perceive subjective boundaries that are not present.
12 months: can detect familiar objects in incomplete drawings, even when as much as two-thirds of the drawing is missing.
176
True/False:
| Newborns show no preference when looking at photos/simplified drawings showing different faces.
False. Newborns prefer to look at photos and simplified drawings of faces with features arranged naturally (upright) rather than unnaturally (upside down or sideways).
They track a face-like pattern moving across their visual field further than they track other stimuli.
Newborns prefer photos of faces with eyes open and a direct gaze.
They have a tendency to look longer at faces judged by adults as attractive.
177
What are two important features of object perception?
1. Size constancy
| 2. Shape constancy
178
Define size constancy
Perception of an object’s size as the same, despite changes in the size of its retinal image
179
Define shape constancy
Perception of an object’s shape as stable, despite changes in the shape projected on the retina
180
When are size constancy and shape constancy evident?
In the first week of life.
181
Both size and shape constancy seem to be ________ capacities that help babies detect a coherent world of objects
built-in
182
At first, infants rely heavily on ______ and ______ __________ to identify objects.
motion, spatial arrangements
183
What is intermodal processing?
making sense of running streams of light, sound, tactile, odour, and taste information, perceiving them as integrated wholes
184
What are amodal sensory properties?
Information that is not specific to a single modality, but overlaps two or more sensory systems
185
How do babies perceive input from different sensory systems in a unified way?
By detecting amodal sensory properties
186
By the second half of the first year, infants can discriminate amodal properties in both _____ and ______ stimulation
intermodal, unimodal (eg. sights or sounds alone)
187
What provides the baby with a rich context for expanding intermodal knowledge?
Early parent-infant interaction
188
According to Eleanor and James Gibson’s differentiation theory, what do infants actively search for?
invariant features: features that remain stable in a constantly changing perceptual world.
189
With experience, perceptual capacities become more _____.
flexible
190
The Gibsons describe their theory as ________, meaning analysing or breaking down, because, over time, the baby detects increasingly fine invariant features among stimuli.
differentiation
191
Perceptual development can be understood as a built-in tendency to search for ____ and ______.
order, consistency
192
According to the Gibsons, perception is guided by the discovery of affordances. What are affordances?
The action possibilities that a situation offers an organism with certain motor capabilities.
e.g. When babies crawl, and again when they walk, they gradually realise that a steeply sloping surface affords the possibility of falling, and as they gain practice with each skill, they hesitate to crawl or walk down a risky incline.
193
Many researchers regard infant development as proceeding from a _______ to a ______ emphasis over the first year of life.
perceptual, cognitive
194
What are the two opposing views theorists hold about the impact of early experiences on development?
Some theorists argue that early experience leaves a lasting imprint on the child’s competence; others believe that most developmental delays resulting from early experiences can be overcome.
195
What has been noted about the development of children reared in severely deprived situations?
They remain substantially below average in physical and psychological development, displaying emotional and behavioural problems throughout childhood.
196
What differences in development have been noted between children adopted from orphanages before the age of 6 months and those who were institutionalised for longer?
Those adopted before 6 months of age showed impressive cognitive catch-up, but those institutionalised for longer showed serious intellectual deficits – among these infants, abnormal development in one domain impeded progress in others.
197
What occurs after babies born with cataracts have corrective surgery within 4 to 6 months?
They show rapid improvement in vision, except for aspects of face perception, but if surgery is delayed, vision is severely and permanently impaired.
198
True/False:
Environments that overwhelm children with expectations beyond their current capacities have a similar effect as environments where stimulus deprivation occurs.
True. Environments that overwhelm children undermine development, causing them to withdraw and threatening their spontaneous interest and pleasure in learning, and thus creating conditions much like those of stimulus deprivation.
