2: Prenatal development Flashcards
At what gestational age does the foetus have fully developed hands?
4 months gestation.
What are the 3 stages of prenatal development?
- Germinal
- Embryonic
- Foetal
The germinal stage is from ________ to _________ (2 weeks). A ________ is formed and divided into 2 sections.
The germinal stage is from conception to implantation (2 weeks). A blastocyst is formed and divided into 2 sections.
What will the 2 sections of a blastocyst form?
- The baby.
2. Supporting structures for development in the womb.
What are the 4 supporting structures for development in the womb? (Hing: PUYA)
- Placenta
- Umbilical cord
- Yolk sac
- Amnion fluid
The embryonic stage leads to ____ development of all ____ _____.
The embryonic stage leads to rapid development of all major organs.
What does ‘organogenesis’ mean?
The production and development of the organs.
At what gestation age does the embryo begin to have a heartbeat?
4 weeks gestation.
At what gestational stage are we most susceptible to environmental adversity?
Embryonic stage.
The foetal stage lasts from __ to __ weeks. _____ structures are ______ and grows to their ____ form.
The foetal stage lasts from 9 to 38 weeks. Basic structures are refined and grows to their final form.
During the foetal stage, the foetus grows from __ inches and __ lbs, to __ inches and __-__ lbs.
During the foetal stage, the foetus grows from 1 inches and 0.25 lbs, to 20 inches and 7-9 lbs.
How many weeks after conception can the sex be determined?
12
How many weeks after conception is the foetus viable to survive outside the womb? What would its approximate weight be?
Week 22/23
500g
Prenatal development of the brain:
When does the first neural tube form?
During the first month.
Prenatal development of the brain:
When are most of the brains neurons in place for synaptogenesis to start?
During the sixth month.
Prenatal development of the brain:
What is synaptogenesis?
The formation of synapses between neurons in the nervous system.
Prenatal development of the brain:
What is synaptogenesis associated with?
New behavioural capacities.
Prenatal development of the brain:
When does the cerebral cortex enlarge?
During the last trimester.
Synaptic blooming and pruning occur ___-nataly.
Synaptic blooming and pruning occur post-nataly.
Different brain regions mature at different times during development. Regions associated with _____ cognitive function develop later.
Different brain regions mature at different times during development. Regions associated with higher cognitive function develop later.
Brain development:
What 3 regions of higher cognitive function undergo rapid growth during the first 3.5 yrs of life?
(Hint: HAC)
- Hippocampus
- Amygdala
- Corpus Callosum
Brain development:
What is the implication towards cognitive development in children if different brain regions mature at different times during development?
During these early months (or years) bee brain may be particularly sensitive to certain experiences. AKA sensitive periods.
Place these sensitive periods in order of which occurs first:
Language Sensory pathways (vision, hearing) Higher cognitive function
Place these sensitive periods in order of which occurs first:
Sensory pathways (vision, hearing) Language Higher cognitive function
Fetal development - behavioural organisation:
When do fetal movements begin to occur?
8 weeks onwards
Fetal development - behavioural organisation:
When are fetal movements felt by the mother?
18-20 weeks
Fetal development - behavioural organisation:
Behaviour becomes progressively more ________ with gestational age.
Fetal development - behavioural organisation:
Behaviour becomes progressively more organised with gestational age.
Fetal development - behavioural organisation:
At what age are there distinct patterns of rest and activity?
34 weeks.
Fetal development - behavioural organisation:
What percentage of time does the foetus spend in a quiet, motionless sleep-like state?
20-30%
Fetal development - behavioural organisation:
What are the three qualities of ‘active sleep’?
- Many body movements.
- Heartbeat and breathing pattern irregular.
- Responsive to sensory stimuli.
Fetal development - behavioural organisation:
At what age does the foetus spend less time in ‘active sleep’, with activity and rest periods alternative cyclically?
38 weeks.
Fetal behaviour and learning:
At what age does the foetus begin responding to sounds?
25th week.
Fetal behaviour and learning:
At what age does the foetus distinguish between familiar and novel stimuli?
32 weeks.
Describe DeCasper and Spence (1986) study of fetal learning.
Results:
Conclusion:
Results:
Infants adapted sucking to hear familiar story instead of unfamiliar one.
Conclusion:
Prenatal learning is retained after birth.
What are the two main causes of abnormalities in prenatal development?
- Genetic/chromosomal causes.
2. External influences.
What are the two main type of external influences to cause abnormalities in prenatal development?
- Teratogens
2. Maternal factors
What are the two main teratogens to cause abnormalities in prenatal development?
- Smoking, alcohol, drugs.
2. Environmental toxins.
What are the 5 main maternal factors to cause abnormalities in prenatal development?
(Hing: PADDE)
- Poverty
- Age
- Diet
- Disease
- Emotional state.
At what prenatal stage is the offspring not usually susceptible to teratogens?
Germinal.
Prenatal susceptibility to teratogenic agents:
At how many weeks of age is the embryo’s heart and CNS susceptible to teratogen agents?
3 weeks
Prenatal susceptibility to teratogenic agents:
At how many weeks of age is the embryo’s eyes and limbs susceptible to teratogen agents?
4-5 weeks
Prenatal susceptibility to teratogenic agents:
At how many weeks of age is the embryo’s ears and teeth (palate) susceptible to teratogen agents?
6-8 weeks
Prenatal susceptibility to teratogenic agents:
At how many weeks of age is the embryo/foetus external genitalia susceptible to teratogen agents?
8-9 weeks
Prenatal susceptibility to teratogenic agents:
At how many weeks of age is the foetus brain susceptible to teratogen agents?
9-16 weeks
Teratogens:
What does smoking influence?
Birth weight.
Teratogens:
What does drinking alcohol influence?
Fetal alcohol syndrome.
Teratogens:
What are the 6 characteristics of fetal alcohol syndrome?
(Hint: PHALLS)
- Physical abnormalities.
- Hyperactivity.
- Anxiety.
- Low birth weight.
- Learning difficulties.
- Small brain.
Teratogens:
What are the 3 prenatal risk factors for cocaine exposure?
(Hint: BNB)
- Brain haemorrhages.
- Neuron damage.
- Behavioural problems.
Describe the results of O’Connor et al. (2003) ALSPAC study on maternal stress on development.
Antenatal depression significantly increased odds for boys and girls to present behavioural and emotional difficulties. Negative effects persisted to age 7 yrs.
Describe the other risk factors that were controlled for in O’Connor et al. (2003) ALSPAC study on maternal stress on development.
(Hint: SAME)
- Smoking
- Alcohol abuse
- Maternal age
- Education
What are the four main difficulties associated with perinatal risks?
- Premature birth.
- Low birth weight.
- Respiratory difficulties.
- Difficult deliveries.
Prematurity:
Babies born at 38-42 weeks are classified as :
Full-term
Prematurity:
Babies born at 38 weeks or less are classified as:
Pre-term
Prematurity:
Babies born at 32 weeks or less are classified as:
Very pre-term
Prematurity:
Babies born at 26 weeks or less are classified as:
Extremely pre-term
Prematurity:
What is the typical weight of a full-term baby?
3,500 grams
7.7 lbs
Prematurity:
What is the typical weight of a very pre-term baby?
1,700 grams
3.7 lbs
Prematurity:
What is the typical weight of an extremely pre-term baby?
700 grams
1.5 lbs
Premature birth and LBW lead to increase risk of impairment, ranging from gross to minor. Typical impairments include:
(Hint: PAMBI)
- Perceptual
- Attentional
- Motor
- Behavioural
- Intellectual
What can help moderate potential adverse effects of prematurity and LBW?
High quality care.
What were the results of Grunau et al (2004) study on extremely low birth weight?
ELBW babies at risk to develop arithmetic difficulties and behavioural problems than controls.
What percentage of births are at risk for disability or abnormality?
10%
What are the two main reasons vulnerable children develop resilience to potential adverse effects of prematurity?
- Brain plasticity.
2. Environmental characteristics.
What are the two main environmental characteristics associated with children developing resilience to potential adverse effects of prematurity?
- Families with good caregiving skills, income and resources.
- Neighbourhood and community.
The acquisition of information through sensory organs and transmission of that information to the brain is called:
sensation.
Name the four type of sensation:
- Seeing
- Hearing
- Tasting
- Smelling
The attribution of meaning to sensations is called:
Perception
The two main types of perception are:
- Visual
2. Auditory
Name 4 type of visual perception:
- Objects
- Faces
- Depth
- Patterns
Name 3 types of auditory perception:
- Distinguishing voices
- Recognising speech
- Language
In newborns, what is the least developed of the senses?
Vision.
According to Simion, Regolin and Bulf (2008) newborns can distinguish between what types of motion?
Human biological motion from random motion.
The clarity/sharpness of vision is called:
visual acuity
Perfect visual acuity in adults is __/__
20/20
Visual acuity in newborns is __/__
20/200
Visual acuity in newborns is approximately __ / __th of an adults.
Visual acuity in newborns is approximately 1 / 30th of an adults.
Control over the eyes to focus is called:
visual accommodation.
Visual accommodation in newborns is poor. They can focus their eyes on the same spot at a distance of __-__ inches.
Visual accommodation in newborns is poor. They can focus their eyes on the same spot at a distance of 8-10 inches.
Who’s face do newborns show a preference for?
Their mothers.
Describe Aslin et al (1987) experiment on infants tracking skills.
Procedure:
Results:
Procedure:
Infants eye movements when looking at a line were tracked at 6 weeks old and then again at 10 weeks old.
Results:
At 6 weeks they followed the line jaggedly, not smoothly. By 10 weeks the same baby skills was remarkably smoother and more accurate.
Describe the results of Schaffer (1985) experiment on visual scanning at 1 and 2 months old.
1 month old:
scanned only small portion of geometric shape.
2 months old:
scanned almost all of geometric shape.
Describe the results of Maurer and Maurer (1998) experiment on visual scanning at 1 and 2 months old.
1 month old:
scanned only a portion of the face, focusing most of the time on chin.
2 month old:
scanned different portions of the face, focusing on different parts of the face for briefer periods, including features typically used to distinguish faces such as eyes, lips and hair.
At what age do babies first focus on where objects are in the world, scanning light and light contrasts for the edge of objects and examining motion?
2 months old.
At what age to babies shift to focus on what an object is, notice a larger degree of detail and begin paying attention to patterns?
2-3 months old.
What are the two main ways Fantz (1956) studied infant perception?
- Visual preference method.
2. Habituation tasks.
Describe the results of Fantz (1958) visual preference task.
Infants looked longer at patterned (e.g. checkered) images rather than uniform images.
Describe the results of Fantz (1964) habituation task.
Over multiple exposures to the same and a different image, the infant gradually exhibited a preference for the novel stimulus.
What did Slater et al (1991) experiment demonstrate?
Infants perceive shapes as wholes rather than angular parts.
What did Kellman and Spelke (1983) experiment demonstrate?
4 month olds perceive objects as a whole, whereas, newborns don’t.
According to Johnson et al (2003) experiment, at what age do we perceive continuity in objects?
6 months old.
According to Johnson et al (2003) experiment, at what age do we perceive continuity in objects only when an occluder is small or over a short time?
4 months old.
According to Johnson et al (2003) experiment, at what age do we perceive a discontinuous trajectory in objects?
2 months old.
According to Johnson et al (2003) experiment, at what age do we perceive subjective contours in objects?
3-4 months old.
According to Fantz et al, at what age can we discriminate between patterned and unpatterned shapes?
2 days old.
According to Fantz et al, at what age can we show preference for certain shapes?
1 weeks old.
According to Fantz et al, at what age do we show preference for simpler patterns?
1 month old.
According to Fantz et al, at what age do we show preference for more complex patterns?
2 months old.
What were the results of Simion et al. (2001) experiment?
Babies prefer up-down asymmetry and congruency.
What was the conclusion/implications of Simion et al. (2001) experiment?
Processing faces is no different from processing any other visual stimuli.
According to Johnson et al. (1991) what are the two processing systems for face perception?
- Motion
2. Identification
What was the result of Langois et al. (1990) study?
Infants prefer attractive faces.
What was the result of Walton et al. (1992) study?
Infants prefer mothers face from birth.
What was the result of Pascalis et al. (1995) study?
No discrimination between faces if hairline covered.
What was the result of Sai (2005) study?
Recognition of mothers voice turns infants attention to face.
What were the results of Johnson et al. (1991) study on newborns tracking of face-like stimuli?
Newborns tracked the face configured stimuli more than the scrambled and blank ones.
What was the result of Meltzoff and Moor (1977) study?
12-21 days old infants imitate the facial expressions of adults.
Which two mechanisms may account for face preference?
- Faces display stimulus characteristics that are inherently appealing.
- Infants born with innate face-detecting brain mechanism.
What 3 stimulus characteristics make faces inherently appealing?
- Areas of high contrast.
- Are top heavy, with more elements in the top than bottom part.
- Move and are dynamic.
An understanding of 3-dimensional space, with a survival value of enabling infants to make accurate reaches and distinguish objects from their background is called:
depth perception.
What was the result of Gibson and Walk (1960) visual cliff experiment?
Babies at 6 months old showed reluctance to cross visual cliff, indicating depth perception.
What was the main limitation of Gibson and Walk (1960) visual cliff experiment?
Requires babies to be able to crawl.
What was the result of Campos et al. (1992) variation of the visual cliff experiment?
Difference in heart rate between infants who can and cannot crawl, but did not indicate fear.
What was the conclusion of Campos et al. (1992) variation of the visual cliff experiment?
Learning not to move onto the deep side of the cliff is a result of experience gained from crawling.
What could be an alternative conclusion of Campos et al. (1992) variation of the visual cliff experiment?
The change in heart rate when placed over the cliff may not indicate fear, but still they did differentiate between the shallow and deep side, suggesting some form of depth perception independent of experience gained from crawling.
In infants, focusing on voices and speech is considered important for the development of ________ and _______.
In infants, focusing on voices and speech is considered important for the development of attachment and language.
Auditory perception begins to develop before birth, with fetal reactions to sound observed at the __th week.
Auditory perception begins to develop before birth, with fetal reactions to sound observed at the 20th week.
Auditory perception:
Give 2 examples of findings that indicate prenatal learning in newborn infants.
- Preference to hear own language over foreign language.
2. Preference to hear familiar story over new story.
At what age can infants distinguish between “ba” and “pa” sounds?
1 month old.
At what age can infants discriminate between 2-syllable words?
6 months old.
At what age can infants respond to syllables hidden inside a string of letters?
6 months old.
At __ months babies can discriminate between all sound contrasts that appear in any language, include languages that have never been spoken to them. They lose this ability at __ months.
At 6 months babies can discriminate between all sound contrasts that appear in any language, include languages that have never been spoken to them. They lose this ability at 12 months.
At 6 months babies can discriminate between all sound contrasts that appear in any language, include languages that have never been spoken to them. They lose this ability at 12 months.
Neurologically speaking, what does this indicate?
Rapid, pre-programmed growth of synapses, followed by synaptic pruning.
What is the most sophisticated of all sense of birth, fine-tuning itself over the house of the first year?
Touch.
The process of integrating information from several sense is called:
intersensory integration
Learning something via one sense and then transferring that information to another sense is called:
Cross-modal transfer
AKA intermodal transfer
Intersensory integration:
At what age do we connect sound rhythms to movement?
4 months old.
Intersensory integration:
At what age do we connect sound and sight to motion?
5 months old.
Intersensory integration:
At what age do we show preference for a face mouthing a vowel we hear being spoken?
4-5 months old.
What was the result of Meltzoff and Borton (1979) study on cross-modal transfer?
4 week old infants prefer looking at a dummy they had previously experience orally.
The acquisition of sensory stimuli and subsequent transmission of that information to the brain is called:
perception.
The attribution of meaning to sensations through mental representations is called:
cognition.
What are the 3 ways we can measure early perception and cognition?
- Preference technique
- Habituation.
- Violation of expectation.
Explain how the preference technique can be used to measure early perception and cognition.
Researchers measure how long a baby looks a a certain stimuli. They use the looking time to infer cognition.
Explain how the habituation technique can be used to measure early perception and cognition.
Presenting the same picture repeatedly until the infant stops looking (habituates). Presents the second stimulus, examining whether the infant shows a renewed interest.
Explain how the violation of expectation technique can be used to measure early perception and cognition.
Measures looking times during unexpected events.
Piaget says that children actively seek new knowledge via experience so that they can construct mental models of the world around them. This is known as:
constructionism.
According to Piaget, what are cognitive schemas?
An enduring knowledge base by which we make sense of our world and organise experience.
According to Piaget, The inborn capacity to coordinate existing cognitive schemas into new and more complex ones is called:
organisation.
According to Piaget, cognition is comprised on which two things?
- Organisation
2. Adaptation
According to Piaget, adaptation is comprised of what 3 processes?
- Assimilation
- Accommodation
- Equilibration
What is ‘assimilation’ under Piaget’s theory?
The process of taking in some event or experience and making it part of a schema.
What is ‘accommodation’ under Piaget’s theory?
Changing a schema as a result of new information.
What is ‘equilibration’ under Piaget’s theory?
The process of bringing assimilation and accommodation into balance.
According to Piaget, what are the 4 stages of development?
- Sensorimotor.
- Pre-operational.
- Concrete operational
- Formal operational.
According to Piaget, at what age does the sensorimotor stage occur?
0-2 yrs
According to Piaget, at what age does the pre-operational stage occur?
2-7 yrs
According to Piaget, at what age does the concrete operational stage occur?
7-11 yrs
According to Piaget, at what age does the formal operational stage occur?
11+ yrs
According to Piaget, what are the 6 milestones achieved in the sensorimotor stage?
- Basic reflex activity.
- Primary circular reactions.
- Secondary circular reactions.
- Coordination of secondary circular reactions.
- Tertiary circular reactions.
- Internalisation of schemas, the origin of symbolic thought.
When an object is hidden from an infant aged 9 months, in a new location to where is was previously hidden, the infant will incorrectly assume the object will be found in the same location as the last time. What would Piaget’s explanation to this be?
Sensorimotor stage, infant has lack of object permanence and inhibitory control.
Describe the method and results of Topal et al. (2008) object retrieval task. (preference task)
Method:
Experimenter places object in one location and infant reaches for it successfully. Experimenter hides object in new place.
Result:
Infants up to 9 months old fail the task and search again in the original location.
Describe a visual habituation technique that can be used to show a 4 month old infants perception of objects is influenced by their level of knowledge.
When shown a video, infants perceive the left hand figure as a continuous rod moving behind an occluder, indicating they perceptually ‘fill in’ the occluded area in the habituation display.
Describe a violation of expectation technique that can be used to show infants perception of objects is influenced by their level of knowledge.
The infant is shown two even sequences, one possible and the other impossible. When viewing the impossible event of a flap rotating through a solid cube, the infants appear surprised and look longer.
During a violation of expectation technique, an infant is shown two even sequences, one possible and the other impossible. When viewing the impossible event of a flap rotating through a solid cube, the infants appear surprised and look longer.
At 4 months old this indicates:
They understand objects are usually solid and non-compressible.
During a violation of expectation technique, an infant is shown two even sequences, one possible and the other impossible. When viewing the impossible event of a flap rotating through a solid cube, the infants appear surprised and look longer.
At 5 months old this indicates:
object permanence.
During a violation of expectation technique, an infant is shown two even sequences, one possible and the other impossible. When viewing the impossible event of a flap rotating through a solid cube, the infants appear surprised and look longer.
At 6-8 months old this indicates:
object permanence and knowledge of solidity and impenetrability of objects.
We possess a knowledge of numbers at age:
3-4 months old.
Recent findings indicate infants have object permanence abilities much ______ than Piaget thought.
Recent findings indicate infants have object permanence abilities much earlier than Piaget thought.
What two main things lead to the development of knowledge in children?
- Environmental influences.
2. Internal constructions.