Psyc2500Chpt.4

Chapter Overview

This chapter on Growth and Health covers various aspects of children's physical development, challenges to healthy growth, and the developing nervous system.

Module 4.1 - Physical Growth

Features of Human Growth

• Rapid Growth Phases: The first year of life is characterized by rapid growth, followed by a leveling off during preschool and elementary years, and then another spurt in early adolescence.

• Growth Patterns: Growth occurs in two main patterns: cephalocaudal (head to foot) and proximodistal (inside out), indicating that control over gross muscles develops before finer motor skills.

• Secular Growth Trends: There are generational changes in physical development, highlighting that average growth standards can shift over time.

• Understanding Average vs. Normal: It’s important to distinguish between what is statistically average and what is considered normal in developmental contexts.

Mechanisms of Physical Growth

• Sleep: Crucial for growth, as 80% of growth hormone is secreted during sleep.

• Nutrition: Infancy requires adequate nutrition, with breastfeeding recommended as the optimal source of nourishment. Beyond infancy, a balanced diet that includes all food groups while limiting sugar and fats is essential throughout childhood.

• Picky Eating: Many preschoolers exhibit picky eating behaviors, which can affect their nutritional intake and growth.

Adolescent Growth Spurt and Puberty

• Significance of Puberty: Marks the biological transition into adolescence, involving various physiological changes.

• Sexual Maturation Differences: The onset and progression of sexual maturation differ between boys and girls, impacting their growth patterns, characteristics, and psychological health.

• Influencing Factors of Puberty Timing: Factors such as genetics, nutrition, and health can affect when puberty begins, and early or late maturing can influence psychological consequences for adolescents.

Module 4.2 - Challenges to Healthy Growth

Overview of Challenges

• Major challenges to healthy growth include malnutrition, eating disorders, obesity, disease, and accidents.

Malnutrition

• Global Concern: Approximately 1 in 3 children worldwide under age 5 suffers from malnutrition. In Canada, nearly 1 in 7 children live in poverty. Food insecurity affects many Indigenous communities.

• Impact on Development: Malnutrition particularly affects cognitive development during infancy and can impair learning capacity.

• Strategies for Improvement: Effective treatments include dietary improvements and training for parents to support healthy development.

Short-Term Hunger and School Success

• Breakfast importance: Children who regularly have nutritious breakfasts tend to perform better academically.

• School Meal Programs: Implementing free and reduced-price meal programs in schools can significantly improve children's food security and educational outcomes.

Eating Disorders

• Types: Anorexia involves refusal to eat and an irrational fear of weight gain, while bulimia is characterized by binge eating followed by purging. These disorders are more prevalent among adolescent girls, influenced by cultural and social pressures. Body Dysmorphic Disorder is also prevalent, especially among boys.

Obesity

• Definition: Obesity is defined as having a body mass index (BMI) in the upper 5%. Approximately 20% of Canadian children are considered overweight.

• Causes and Consequences: Factors include genetics, lifestyle, and parental influence, while obesity is linked to low self-esteem and physical health issues.

• Treatment Approaches: Successful weight-loss programs should involve family support, lifestyle changes, and regular exercise.

Disease

• Child Mortality: Nearly 8 million children die before age 5 globally, with diseases like pneumonia, diarrhea, and malnutrition being leading causes. Enhanced healthcare and preventive measures are crucial.

Accidents

• Leading Cause of Death: Car accidents rank as the leading cause of death for children in North America over the age of one. Preventative measures include proper safety equipment and parental guidance on appropriate risk-taking.

Module 4.3 - The Developing Nervous System

Organization of the Mature Brain

• Basic Units: Neurons are the fundamental units of the nervous system responsible for information transmission.

• Key Structures: Neurons consist of a cell body, dendrites, axons, and myelin, with neurotransmitters facilitating communication across synapses.

• Cerebral Cortex: This part of the brain includes the left and right hemispheres and is crucial for higher-order functions, while the frontal cortex governs personality and planning capabilities.

The Developing Brain

• Developmental Timeline: The brain starts as a neural plate during prenatal development. Myelination begins before birth and continues into adolescence, enhancing coordination and response times.

• Postnatal Growth: After birth, rapid brain growth occurs, with synaptic pruning eliminating unnecessary neuronal connections to refine brain function.

Brain Function Monitoring

• Techniques: EEG and fMRI technologies allow for observation of brain activity, providing insights into the functional aspects of brain development.

• Specialization and Plasticity: Brain regions specialize early, with differing rates of development and focus. Young children exhibit significant plasticity, allowing them to adapt, although there are limits.

Educational Implications

• Brain-based Education: The growing field of brain-based education seeks to link neuroscience with educational practices, though a comprehensive curriculum based on neuroscience is not yet established.