Developmental Psychology: Conception Through Young Adulthood

Stages of Prenatal Development

Human development begins at conception and progresses through several distinct prenatal stages, each characterized by unique physiological changes and vulnerabilities.

• Pre-embryonic Stage (Conception to 3rd week): Characterized by the formation of three primary cell layers: endoderm, mesoderm, and ectoderm.

• Embryonic Stage (4th to 8th week): All basic organs are established. This is the period of greatest vulnerability to teratogens (substances that cause congenital anomalies), such as alcohol, tobacco, and drugs.

• Fetal Stage (9th week to birth): Body organs and systems continue to grow and mature.

Example: Exposure to alcohol during the embryonic stage can result in fetal alcohol syndrome due to rapid organ development.

Physical and Reflex Development in the Neonate (Birth to 28 Days)

Neonates exhibit several innate reflexes and physiological characteristics that support survival and adaptation to the environment.

• Reflexes: Moro, stepping, grasp, hand-to-mouth, sucking, swallowing, blinking, sneezing, yawning.

• Temperature Regulation: Body temperature responds quickly to environmental changes.

• Sensory Response: Senses are used to respond to environmental stimuli.

• Elimination: Stool and urine are eliminated regularly.

• Behavioral States: Active crying and quiet alert states are exhibited.

Health and Immunity in the Neonate

• Inherited Immunity: Maternal immunoglobulins cross the placenta, providing temporary immunity.

• Breastfeeding: Recommended exclusively for the first 6 months; provides additional immune protection.

• Risks: Premature or cesarean-delivered neonates are more vulnerable to respiratory distress syndrome and other complications.

Physiologic Development of the Infant (1 Month to 1 Year)

Infancy is marked by rapid physical growth and neurological development.

• Brain: Grows to half of adult size.

• Motor Skills: Development of motor abilities; eyes begin to focus and fixate.

• Cardiovascular: Heart doubles in weight, heart rate slows, blood pressure rises.

• Teeth: Deciduous teeth begin to erupt at 4-6 months.

• Weight: Birth weight typically triples by 1 year (average 22 lb).

Psychosocial Development of the Infant

• Freud's Oral Stage: Immediate gratification of needs through oral activities.

• Erikson's Trust vs. Mistrust: Development of trust when caregivers provide reliability, care, and affection.

• Havighurst's Developmental Tasks: Taking food, walking, and talking.

Special Considerations for the Infant

• Attachment and Bonding: Bonding occurs shortly after birth and is necessary for later attachment.

• Play: Essential for sensory and motor development.

• Temperament: Easy, slow to warm, or difficult.

• Health Risks: Infant colic, failure to thrive, accidental injuries, SIDS, and child maltreatment.

Role of the Nurse in Infancy

• Health Promotion: Teaching family members and caregivers is the most essential role.

• Safety, Nutrition, Hygiene: Guidance on these aspects is crucial for healthy development.

• Immunizations: Administering and educating about vaccines.

Physiologic Development of the Toddler (1 to 3 Years)

Toddlers experience rapid growth and increased independence.

• Growth: Rapid brain growth, increased bone length, and muscle development.

• Motor Skills: Uses fingers to pick up small objects, walks, runs, climbs, rides tricycle, drinks from cup, uses spoon.

• Weight: Four times birth weight by age 3.

• Bladder Control: Achieved during the day, sometimes at night.

• Fine Motor: Turns pages, draws stick people by age 3.

Cognitive Development of the Toddler

• Piaget's Sensorimotor Stage: Final two stages; beginning of object permanence.

• Language: Begins to use short sentences by age 2.

• Self-Concept: Understands self as separate from others; begins to perceive body image and biological sex identity.

Psychosocial Development of the Toddler

• Freud's Anal Stage: Toilet training is a major focus.

• Erikson's Autonomy vs. Shame and Doubt: Developing independence; negativism and regression may occur.

• Havighurst's Tasks: Control elimination, learn sex differences, form concepts, learn language, distinguish right from wrong.

Role of the Nurse: Health of the Toddler

• Accident Prevention: Highest risk for toddlers; teaching is primary intervention.

• Encouraging Independence: Caregivers should set firm limits while promoting autonomy.

• Health Promotion: Safety, nutrition, hygiene, elimination, growth, and illness prevention.

Physiologic Development of the Preschooler (3 to 6 Years)

• Growth: Head nears adult size by age 6; body becomes leaner and more coordinated.

• Motor Skills: Jumping, skipping, throwing, printing letters and numbers.

• Teeth: Full set of 20 deciduous teeth.

• Weight: Average 45 lb.

Cognitive Development of the Preschooler

• Egocentrism: Decreases as socialization increases.

• Play: Becomes more related to real-life events.

• Curiosity: Results in constant questioning and improved reasoning.

• Language: Becomes more elaborate.

Psychosocial Development of the Preschooler

• Freud's Phallic Stage: Biologic focus is genital.

• Erikson's Initiative vs. Guilt: Conscience develops; child learns to initiate activities.

• Havighurst's Tasks: Learn sex differences and modesty, describe reality, prepare to read, distinguish right from wrong.

• Kohlberg's Preconventional Morality: Behavior is dominated by obeying rules to avoid punishment or receive rewards.

Role of the Nurse: Health of the Preschooler

• Obesity Prevention: Identify at-risk children and educate families.

• Communication: Explain procedures in child-friendly language; encourage expression of feelings.

• Family Involvement: Encourage caregivers to participate in care.

Physiologic Development of the School-Aged Child (6 to 12 Years)

• Brain: Reaches 90-95% of adult size; nervous system matures by age 12.

• Motor Skills: Progress to writing in script and sentences.

• Technology: Digital natives interact with computers and learning systems.

• Sexual Development: Sexual organs grow but remain dormant until late in this period.

• Teeth: All permanent teeth except 2nd and 3rd molars by age 12.

• Growth: Height increases 2-3 inches/year; weight increases 3-6 lb/year.

Cognitive Development of the School-Aged Child

• Piaget's Concrete Operational Stage: Organizes facts, solves problems using inductive reasoning, develops concepts of measurement and classification.

• Social Awareness: Understands others' feelings, reversibility of events, and generalizes about people and things.

• Language: Well-developed skills.

Psychosocial Development of the School-Aged Child

• Freud's Latency Stage: Strong identification with own sex.

• Erikson's Industry vs. Inferiority: Focus on learning useful skills; self-identity emerges.

• Havighurst's Tasks: Learn physical games, social roles, academic skills, independence, conscience, morality, and values.

• Kohlberg's Conventional Morality: Moral development focuses on conforming to social rules.

• Fowler's Spiritual Development: Spiritual beliefs may begin to form.

Health Issues for School-Aged Children

• Obesity

• Accidents

• Communicable conditions

• Attention deficit hyperactivity disorder (ADHD)

• Seizure disorders

• Hypertension

• Type 1 diabetes mellitus

• Scoliosis

• Learning disabilities

• Chronic illnesses

• Enuresis (bedwetting)

Role of the Nurse: Health of School-Aged Children

• Education: Individual and family teaching on health, safety, and development.

• Obesity Prevention: Encourage physical activity.

• Violence and Bullying: Recognize and address these issues.

• Hospitalization: Allow some control to reduce anxiety.

Physiologic Development of the Adolescent (12 to 18 Years)

• Growth: Rapid growth of feet, hands, and long bones; increased muscle mass.

• Puberty: Primary and secondary sexual characteristics develop; begins at 9-13 years in girls, 10-14 years in boys.

• Glands: Sebaceous and sweat glands become active.

• Adult Size: Usually reached by late adolescence.

Three Stages of Puberty

Cognitive Development of the Adolescent

• Piaget's Formal Operations: Deductive, reflective, and hypothetical reasoning; abstract thinking; long-term goal setting.

• Egocentrism: Returns; imaginary audiences and daydreaming are common.

Cognitive Development of the Young Adult

• More creative, objective, and realistic than adolescents.

• Less self-centered; learning is enhanced by life experiences.

Psychosocial Development of the Adolescent and Young Adult

• Freud's Genital Stage: Capable of full sexual function.

• Erikson's Identity vs. Role Confusion: Self-concept stabilizes; peer group is highly influential.

• Havighurst's Tasks: Develop masculine/feminine roles, internalize values and ethics.

• Levinson's Early Adult Transition: Initial career choices, personal relationships, and value selection.

• Gould's Theory of Transformation: Young adults establish independence from family.

Special Considerations for the Young Adult

• Choosing an occupation or career

• Establishing a family

• Moral development: Conventional level, with some entering postconventional stage

• Spiritual development: Individuating-reflective period (Fowler)

Health Issues for Adolescents and Young Adults

• Injuries

• Substance use, misuse, and abuse

• Suicide

• Pregnancy

• Nutritional problems

• Sexually transmitted infections (STIs)

• Developmental and situational stressors

Developmental and Situational Stressors

• Sexual orientation and gender identity

• Peer pressure

• Family stressors

• Pressures to marry, desire for love and belonging

• Financial pressures, divorce, and separation

Role of the Nurse: Health of Adolescents and Young Adults

• Assess changes in reproductive functioning

• Facilitate healthy family relationships

• Provide educational and recreational activities during illness or hospitalization to reduce isolation