Psychology: Prenatal Development, Infancy, and Sensory-Motor Milestones

What begins human conception?

The penetration of a sperm into the membrane of an ovum (egg).

What is formed when a sperm and egg unite?

A zygote, which contains a complete set of genetic instructions.

What is the basic unit of genetic instruction?

The gene.

How many chromosomes do typical human cells have?

23 pairs of chromosomes.

What determines a person's sex?

The 23rd pair of chromosomes; XX for females and XY for males.

What are identical twins also known as?

Monozygotic twins, originating from the same zygote.

What are fraternal twins also known as?

Dizygotic twins, originating from the fertilization of two eggs.

What are the three stages of prenatal development?

The germinal stage, the embryonic stage, and the fetal stage.

What occurs during the germinal stage?

Formation of the zygote and attachment to the uterine wall.

What major developments occur during the embryonic stage?

Development of major structures and organs of the body.

What is the developing organism called during the fetal stage?

A fetus.

What are teratogens?

Environmental agents that impair prenatal development.

What is fetal alcohol syndrome (FAS)?

A range of severe effects in a child due to maternal alcohol consumption during pregnancy.

What recent controversy involves acetaminophen during pregnancy?

Prolonged use may be linked to ADHD and autism spectrum disorder in offspring.

What did Masarwa et al. (2018) conclude about acetaminophen use during pregnancy?

It is associated with increased likelihood of ADHD and ASD, but findings should be interpreted with caution.

What is the best strategy regarding alcohol consumption during pregnancy?

To avoid alcohol and other teratogens entirely.

How does the timing of teratogen exposure affect fetal development?

It can affect different structures at different stages; for example, early exposure may affect eye formation.

What is the role of genetic code in prenatal development?

It primarily dictates the development process, influenced by environmental factors.

What is the significance of the hippocampus in relation to memory?

It is not fully developed at birth, which is why we have no explicit long-term memories from that period.

What happens to the zygote after implantation?

It leads to the formation of the placenta and umbilical cord.

What is the importance of the placenta?

It allows oxygen and nutrients from the mother to enter and wastes to exit the developing organism.

What is the genetic contribution from each parent to the zygote?

Half of the genetic instructions come from the father and half from the mother.

Why can siblings from the same parents look very different?

Due to the random combination of chromosomes and genetic variation.

What is the typical duration of the germinal stage?

About two weeks.

What major changes occur during the fetal stage?

Rapid growth and completion of body structures and organs.

What can impair prenatal development aside from teratogens?

Maternal health factors, such as nutrition and diseases.

What is the role of environmental factors in prenatal development?

They can significantly influence the development alongside genetic factors.

What is recommended for fever and pain during pregnancy?

Acetaminophen can be taken for a short period, but further treatment should be consulted with a physician.

What maternal age factors increase health risks to the fetus?

Mothers who are very young (15 or younger) or older (over 35) face increased health risks.

What are common risks associated with prematurity?

Major health problems include immaturity of the lungs, digestive and immune systems.

What is the significance of low birth weight?

Low birth weight increases the chances of neurological disabilities and death.

What percentage of prematurity cases have no identifiable cause?

About 50% of prematurity cases have no identifiable cause.

What hormonal changes occur during pregnancy?

Pregnancy involves radical hormonal surges, especially in sex steroid hormones like estrogen and progesterone.

What brain changes occur in first-time mothers after pregnancy?

Significant reductions in gray matter volume in areas related to understanding others' thoughts and feelings.

How long do brain changes in mothers last after pregnancy?

These brain changes last at least 2 years, except in the hippocampus.

What are the two major areas of development during infancy?

Motor development and sensory-perceptual development.

What are some examples of motor reflexes present at birth?

Breathing reflex, Babinski reflex, grasping reflex, sucking reflex, rooting reflex.

What is the sequence of motor development in infants?

Infants learn to prop up, sit, crawl, stand with support, stand without support, and walk by around 12 months.

What factors influence the learning of walking in infants?

Strength, body proportions, and balance interact to influence walking development.

How does crawling affect infants' perception of heights?

Crawling infants develop a fear of heights, while non-crawling infants do not show this fear.

What is the preferential-looking technique?

A method to study vision in infants by displaying two visual stimuli and recording which one they look at longer.

What does habituation in infants indicate?

A decrease in physiological response to a familiar stimulus, indicating they can perceive differences.

How do infants respond to novel stimuli?

Infants intensify sucking of a pacifier when confronted with a novel stimulus.

What is the relationship between sensory-perceptual development and motor skills?

Sensory-perceptual development helps infants coordinate body movements with perceptual input.

What is the role of gray matter reduction in mothers' brains?

It prepares women for motherhood by enhancing their ability to understand their infant's needs.

What is the impact of teratogens on prenatal development?

Teratogens increase the likelihood of prematurity and other health risks to the fetus.

What is the significance of the hippocampus in new mothers?

The hippocampus recovers quicker, which may be necessary for learning required of new mothers.

What is the Babinski reflex?

An infant reflex where toes fan upward when the feet are touched.

What is the grasping reflex?

An infant reflex where they grasp any object that touches their palms.

What does the rooting reflex help infants do?

It helps infants turn their mouths toward anything that touches their cheeks to search for nourishment.

What is the significance of motor reflexes for infant survival?

Some reflexes, like the sucking and rooting reflexes, are critical for obtaining nourishment.

What developmental changes occur in infants' depth perception?

Crawling infants develop a fear of heights, indicating changes in depth perception.

What is the role of biological adaptations during pregnancy?

Biological adaptations prepare the mother's body to maintain the fetus throughout its development.

What biological mechanism can indicate infants' perceptual behavior?

Changes in heart rate

At what age are the five senses functional in infants?

At birth, though not fully developed

Which sense is the least developed at birth?

Vision

What is the estimated visual acuity of newborns?

About 20/400 to 20/800

When does visual acuity ideally reach 20/20 in infants?

Within the first year of life

At what age does color vision develop to be comparable to adults?

By 2-3 months of age

What apparatus is used to test depth perception in infants?

The visual cliff

What behavior do infants demonstrate on the visual cliff?

Refusing to crawl toward a perceived steep drop-off

What age range of infants was tested in the visual cliff experiments?

Ages 6 to 14 months

What physiological response do crawling infants show on the deep side of the visual cliff?

Accelerated heart rate (a fear response)

What is the role of locomotor experience in depth perception development?

It helps infants learn to fear heights

What visual preference do infants have?

A preference for faces, especially their mother's face

What is the significance of visual complexity for infants?

It is necessary for proper development of visual pathways and cortex

What is the Thatcherization illusion?

An illusion created by rotating the eyes and mouth of a face 180°

How do adults respond to Thatcherized faces when viewed upright?

They readily detect changes in face patterns

What effect does face orientation have on infants' ability to discriminate faces?

Newborns can discriminate upright faces but not upside down faces

What conclusion did Leo and Simion reach about newborns' sensitivity to faces?

Newborns are sensitive to the configural information of faces

What technology allows researchers to assess fetal visual behavior?

Ultrasound technology, referred to as 'womb with a view'

What does the 'womb with a view' technology project?

Light conveying perceptual content that can be perceived by the fetus

What did (2017) find regarding fetal head turns towards stimuli?

Fetuses preferred upright facelike stimuli over inverted ones, indicating an innate preference for configural information in faces.

How developed is hearing in newborns compared to vision?

Hearing is more fully developed than vision in newborns.

What ability do newborns have regarding their mother's voice?

Newborns can distinguish their mother's voice from those of others.

What did DeCasper & Spence's (1986) study demonstrate about prenatal learning?

Infants preferred the familiar story, 'The Cat in the Hat,' that their mothers read to them during pregnancy.

What did Spence and Freeman (1996) find about infants' preferences for voices?

Infants preferred their mothers' voices over those of other women when muffled to simulate womb conditions.

What do infants prefer in terms of sound?

Infants prefer the sound of the human voice and speech sounds over other types of sounds.

By what age does an infant's auditory processing become nearly adultlike?

By 6 months of age.

What are phonemes?

Phonemes are the smallest distinctive speech sounds in a language.

What ability do infants have regarding phoneme detection?

Infants can detect all phonemes, regardless of exposure, soon after birth.

What happens to infants' ability to detect non-native phonemes by 12 months?

They lose the ability to easily detect speech sounds not in their native language.

What is required to maintain the ability to detect non-native phonemes?

A brief amount of exposure through live social interaction.

What senses are well developed at birth?

Smell, taste, and touch are fairly well developed at birth.

How can infants differentiate their mother's smell?

Infants spend more time turned toward their mother's nursing pad compared to another woman's pad.

What innate understanding do infants have regarding object movement?

Infants understand that objects cannot go through solid surfaces.

What cognitive abilities have researchers suggested infants may possess?

Infants may perform simple mathematical operations like addition and subtraction.

What is the state of an infant's brain at birth?

The brain contains about 100 billion neurons but is immature, needing connections to be formed.

What happens to neural connections during the first few months of life?

There is a large growth spurt for connections, especially in the cortex controlling perception and cognition.

What is the consequence of not having visual experiences during infancy?

Visual pathways do not develop, leading to permanent vision loss.

What reflexes are critical for an infant's survival?

The rooting and sucking reflexes are critical for nourishment.

What motor skills do infants learn in their first year?

Infants learn to sit, stand, and walk in an orderly sequence, building upon previous skills.

What happens to neural networks that are not used during infancy?

They disappear, while the networks that are used become stronger.

What are some risks to newborns related to prenatal factors?

Prematurity, low birth weight, and prolonged acetaminophen use during pregnancy.

How does pregnancy biologically impact mothers?

Pregnancy leads to surges in sex steroid hormones and reductions in gray matter volume for first-time mothers.