CHAPTER 5 – PHYSICAL DEVELOPMENT
BIRTH AND THE PRENATAL PERIOD
LABOUR AND DELIVERY
• Around 38 weeks a woman will go into labor initiated by changes in the fetal brain.
• Chemicals are released hat signal the muscles of the uterus to start contracting rhythmically.
• Labor consists of three stages:
1. Neck of the uterus dilates
2. Baby is delivered
3. Placenta is expelled (afterbirth)
• Screening of heart rate can reveal fetal diseases, which would be indicated by either high or low heart rate.
• Caesarian Section can be due to:
o Baby’s head being too large to pass
o Baby lying in an unusual position (butt down or sideways)
o Delivery proceeding too slowly
• Caesarian = 26% of all births in 2005
• Such deliveries pose greater risk of infection to the mother and expose individual to higher levels of medication intake.
Acts like a ‘coach’ during labor and delivery
Nonmedical services (birth assistant)
Is a registered health care professional who provides primary care to lowrisk women throughout their pregnancy, labor and birth and provides care to both mother and baby during the first six weeks following the birth.
CULTURAL ATTITUDES TOWARDS CHILD BIRTH
• In Western countries, pregnancy is viewed as a disease. Must go to the doctor, laying down during birth, given drugs to block
pain, and doctors taking care of baby after birth.
• Cuna Indians of Panama pregnant woman visits medicine man for herbal medicines daily. And medication throughout
• Jarara of South America labor and birth are part of daily life and women give birth in front of everyone.
• NonWestern: women give birth standing or squatting.
• Culture also affects the chance of survival during pregnancy birth. (Likely because of improved health care.)
Childbirth classes provide information about pregnancy and childbirth
Childbirth classes teach pain control through deep breathing, imagery, and supportive coaching
Mothers who attend classes use less medication during labor
CONCEPT OF RISK
At risk: babies who have a higher likelihood of experiencing developmental problems.
THREE CATEGORIES OF INDICATORS OF RISK:
• Maternal and Family Characteristics (85%)
o Poor financial stability and social support
o Infections or diseases
• Physical Compromise of the Newborn (low birth weight, irregular heart beat, irregular breathing…)
o Anoxia: deprivation of oxygen to the cells causing them to die.
o Preterm: babies born prematurely (before the 38 weeks end) o Small for Gestational Age: Low birth weight for their age of development.
• Physical and Behavioral Assessments (tests to screen for disorders)
o Can scan for more than 85% of disorders
o Apgar Exam: focuses on five of the newborns vital functions heart rate, respiration, muscle tone, response to
mildly painful stimulus and skin color. Rated each category from 02.
o Brazelton Neonatal Behavioral Assessment Scale: Assessors observe baby in a number of states or levels of
alertness to obtain a sense of baby’s style of temperament and ability to habituate. Includes 4 categories: attention
and social responsiveness (response to rattle), muscle tone and physical movement, control of alertness
(habituation, irritability and excitability) and physiological response to stress.
Prematurity Stereotyping: tendency to expect negative behavior from premature infants.
**IMPORTANCES OF PARENTBABY CONNECTION FOLLOWING BIRTH NO INCUBATOR ISOLATION**
1. Infant positioned upright on mother/father’s chest 24hours/day until Full term gestational age
2. Kangaroo nutrition breastfeeding and vitamin supplements
3. Clinically monitored until gaining minimum of 20g every day – then monitored weekly until FGA
STATES OF ALERTNESS
* Measured with the use of an EEG* Rapid Eye Movement (REM SLEEP): active sleep where eyelids are closed but eyes can be seen moving back and forth.
• Sudden and unexpected death of an infant under age of 1 year.
• Most vulnerable = 2 to 4 months
o Position in which sleeping – on back is better
o Soft bedding and overheating
o Maternal Smoking or drinking
Circadian Rhythm: regular and predicable pattern of daily activity. Sleeping at night and awake during the day.
Cycle of sleep that repeats every 50 – 60 minutes
Cycle of wakefulness that repeats every 34 hours
Reflex: an automatic and stereotyped response to a specific stimulus
Rooting Reflex: First to appear. Stroke a newborns cheek next to mouth and he searches for touch with his mouth. Disappears around
Palmar Reflex: Pressure against newborns hand and baby responds by grasping tight. Disappears at 34 months, regain at 4/5.
Moro Reflex: reactions to sound or loss of head support. Infant thrusts arms open, open hands, arches back and stretches legs, without
is a sign of brain damage. Failure to disappear after 67 months is also a concern.
Stepping Reflex: pressure applied to soles of feet and baby flexes his legs up and down. Disappears by 3 months. CONGENITALLY ORGANIZED BEHAVIORS
Early behaviors of newborns that do not require specific external stimulation and that show more adaptability than simple reflexes.
Can be divided into two categories:
1. Postural Development or Locomotion: control of the trunk of the body and coordination of arms and legs for moving around.
2. Prehension: ability to use the hands as tools for such purposes as eating, building and exploring.
1. Proximodistal direction: body parts closest to the centre of the body come under control before parts further out.
2. Cephalocaudal direction: head to foot direction.
Dynamic Systems Approach: Thelen’s model of development of motor skills in which infants who are motivated to accomplish a
task create a new motor behavior from their available physical activities. Involves both nature and nurture.
THREE SETS OF FUNDAMENTAL MOVEMENT SKILLS EMERGE:
1. Locomotor movements walking, running, jumping, hopping, climbing…
2. Manipulative movements throwing, kicking, catching, dribbling…
3. Stability movements bending, turning, swinging, rolling… PHYSICAL GROWTH
GROWTH IN SIZE
CHANGES IN BODY PROPORTION AND COMPOSITION (ex: head size relative to body size)
PUBERTY – period in which chemical and physical changes in the body occur that enable sexual reproduction
FACTORS THAT AFFECT GROWTH AND MATURATION
NUTRITION (anorexia, bulimia, obesity)
ABUSE AND PHYSICAL TRAUMA
STRUCTURE OF THE BRAIN
Neurons: Nerve cells in the brain, which transmit activity through axons and dendrites
Myelin ensures effective and speedy message transmissions
Neurons send electrical signals which cross the synapse by the flow of neurotransmitters
The brain has three major parts :
The cerebrum includes the two hemispheres, which are lateralized (left and right sides have specialized functions)
Psychologists are most interested in the cerebal cortex, a thin shell of grey matter covering the brain
Cerebal cortex: appears to be the most recently evolved part of the brain; crucial for functioning of the senses,
language, memory, thought, decision making Three phases of brain development:
Cell production: Neurons are produced between 10 and 26 weeks postconception
Cell migration: Nerve cells travel from inner neural tube outward to final location
Cell elaboration: Synapses are formed, nerve cells are “pruned”
CHAPTER 7 – SENSORY AND PERCEPTUAL DEVELOPMENT
Sensation: Detection of sensory information
Perception: Interpretation of sensation o Organization and understanding of meaning of sensations
Attention: Selective perception
o Focus on certain stimuli while ignoring others
Environmental/learning: Emphasizes the role of experience in organizing complex perceptions from simple sensations
Ethology: Emphasizes the innate aspects of perception that allow a baby to understand the world
CognitiveDevelopmental: Emphasizes the impact of knowledge on perception
Constructivist View states that perception is a cognitive construction based on sensory input plus information retrieved from
o Perception, is a representation of world that builds up as infant constructs an image of experiences (Piaget,
Ecological View states perception has functional purposes of bringing organism in contact with environment and of
increasing adaptation (Gibson)
The Preference Method is a simple procedure in which at least two stimuli are presented simultaneously to see whether
infants will attend more to one of them than the other(s). Shortcoming: no response = ?
The Habituation Method is the process whereby a repetitive stimulus becomes so familiar that responses initially associated
with it no longer occur.
Evoked Potentials another way of determining what infants can sense is to present them with a stimulus and record their brain
HighAmplitude Sucking provides infants with a special pacifier containing electrical circuitry that enables them to exert some
control over the sensory environment. Pain: Babies react with cries and heart rate changes to skin damage (pin prick)
The infant’s nervous system is definitely capable of experiencing pain
Receptors for pain in the skin are just as plentiful in infants as they are in adults.
Babies’ behavior in response to a painprovoking stimulus suggests that they experience pain.
Touch: Sensitivity to touch can be demonstrated in the womb
Tactile stimuli elicit a variety of reflexes in the newborn (rooting, palmar reflexes)
Haptic perception: Recognition of objects by touch
Smell: Babies react with facial expressions
Positive: Banana, strawberry, vanilla
Negative: Rotten eggs, fish
6dayolds turn more frequently toward mother’s breast pad of amniotic fluid than another woman’s
Taste: Various tastes will either elicit a facial expression or change the rate of sucking (e.g. sweet tastes)
Sweeter = suck harder
At 2 hours of age babies make facial expressions for sweet and sour tastes
Vestibular sensitivity: Sensory feedback from vestibular organs maintains balance and body posture. Disturbance in vestibular
senses cause dizziness and inability to remain standing.
Newborns are sensitive to vestibular motion along three axes: front to back, up and down & side to side
Posture can alter alertness in babies (more alert in vertical than horizontal)
Development of vestibular sensitivity and posture is a necessary scaffold for the development of motor skills
Visual cues can outweigh vestibular cues
Fetus can hear: A 28weekold fetus shows reactivity to sound (eyelids clamp)
Newborn babies show changes in sucking rate to mother versus a strange female
Newborns can discriminate mother’s (but not father’s) voice from that of strangers Newborns can discriminate familiar stories from new stories
Newborns can discriminate languages
Newborns are better at hearing low frequencies than high frequencies
Babies are soothed by low frequency sounds
Newborns can distinguish sound location
Newborn babies can differentiate light from dark
Newborn babies are sensitive to movement (mobiles)
Visual acuity: The clarity of visual images
The visual acuity of a newborn is 20/400 to 20/800
The neural circuits that govern visual accommodation (flexing of lens) are not functional in a newborn
Color vision is present, but not fully developed in newborns; it is much improved by 3 to 4 months– related with the
maturation of color receptor cells
Preference method: if infant stares at something longer, it shows they have a preference which means they can differentiate
between two stimuli.
Visual acuity: clarity at which objects are perceived.
Visual accommodation: automatic adjustment of the lens to produce a focused image of an object.
o Size and shape constancies: present at birth
Cube study (Slater et al., 1990) – same cubes, different sizes presented at different distances from the
o Brightness constancy: present by 2 months
o Colour constancy: present by 4 months
^ _____ remains the same even though the _________ reflected on the lens of the eye changes. Infants are able to perceive depth by 7 months
Avoid crawling across a visual cliff
Show changes in heart rate when exposed to a sharp dropoff
Pictorial cues help indicate distance through picture like information: includes convergence, relative size, and
3montholds are able to use some pictorial cues
Kinetic cues: Cues produced by movement
Motion parallax: Objects that are closer to us show greater apparent movement than do further objects
Infants can make some use of the kinetic cues at 1 to 3 months of age
An object that partially occludes another object is perceived as closer
Objects nearer the horizon appear farther
Small images on the retina are perceived as being far away
Understanding of space tied to one’s body and actions
Understanding of space tied to landmarks in environment. Use landmarks to find objects – provide cues that do not change as
babies move around
Self produced movement does not facilitate understanding of location 6 month olds turned to the left landmark or not
11 months used landmark if present
16 months responded correctly, landmark or not
Intermodal perception: The ability to realize that cues from different senses go together
Exploratory intermodal relations: Infants’ inborn ability to relate different sensory modes
Intermodal representation: The ability to develop mental representations that bridge haptic (touch) and visual modes as well as
auditory and visual modes
Defensive reflex: natural reaction to stimuli that tends to protect the organism from further stimulation.
Selective attention: present in infancy
Components of selective attention
Attentional popout and visual search
Inhibition of return
Active inhibition of nonselected items
Selective attention: develops as children get older
Improvements in older children include
Control of attention
Adaptability of attention to the task
Planfulness Adjusting attentional strategies
As children grow older, they become more efficient in their scanning
Older children are
More careful in gathering visual information
More flexible in their search strategies
Less likely to be distracted in their visual searches
CHAPTER 8 – COGNITIVE DEVELOPMENT
Cognition: Higher order mental processes by which humans understand and adapt to the world
Developmental psychology seeks to understand how the form and function of cognition changes across the life span
“My central aim has always been the search for the mechanisms of biological adaptation and the analysis and epistemological
interpretation of that higher form of adaptation which manifests itself as scientific thought”
• First to suggest that children see the world differently to adults.
• First to develop methods to investigate this.
• First to offer a systematic theoretical account of the process of mental growth. Piaget was trained as a biologist and as a philosopher
Piaget’s view of the intellectual development of the child reflected an interaction between biology and experience
Principles of knowledge
Seek the organization by which the child understands the world
Identify the functional