Chapter 1: Overview of Human Growth and Development

Terminology in Reference to Body Parts:
- Distal: Refers to parts that are further away from the center of the body (e.g., hands and feet are distal to the chest and shoulders).
- Proximal: Refers to parts that are closer to the center of the body.
Cephalocaudal (top to bottom)
Proximodist (Growth from the center out)
Neuronal Development Moving Proximally to Distally:
- Coordination and control of muscles develop from the center outwards, leading to early control in proximal muscles (e.g., biceps and triceps) before developing finer control in distal muscles (e.g., hands and fingers).

Rapid Growth Phases:
- Notable early growth occurs from ages 0 to 2, marked by significant increases in height and weight per year.
- After age 2, growth rates slow down, leading to a gradual increase until puberty, where another growth spurt occurs.
Sex Differences in Growth:
- Boys and girls exhibit different growth patterns with girls experiencing growth spurts earlier (around ages 10-11) compared to boys (around 12-13).
- General Growth Patterns:
- Height and weight gain show spikes around age 2 and again at puberty.

Definition:
- Secular growth trends refer to generational differences in physical development, often attributed to improved nutritional access and other environmental variables.
Comparative Analysis of Height Across Generations:
- Adults born more recently (e.g., 1996) tend to be taller than those born historically (e.g., 1896) due to improved nutrition.
- Populations in countries like the US, the Netherlands, South Korea, and Japan show marked differences in heights, attributed to varying nutritional access.

Importance of Growth Hormone:
- Approximately 80% of growth hormone is secreted during sleep; disruptions in sleep negatively affect physical growth.
Consequences of Sleep Deprivation:
- Decreased attention, cognitive functioning, increased anxiety and depression, and lowered self-esteem.
Parenting Strategies for Sleep:
- Implementing bedtime routines that may include winding down activities like reading, which signals the child it's time to sleep, promoting restful sleep conducive to growth.

Caloric Requirements:
- Infants need approximately 100 calories per kilogram of body weight daily, while adults need about 30-40% of that amount.
Breast Milk vs. Formula:
- Breastfeeding is optimal for early development due to essential nutrients and antibodies; assists with digestion and transitioning to solid foods.
- Formula can be a flexible alternative but lacks certain antibodies found in breast milk.

Caloric Needs for Toddlers:
- Require about 90% of the caloric intake compared to infants.
Picky Eating Challenges:
- Strategies to encourage healthy eating include:
- Offering choices of healthy options to promote autonomy.
- Allowing kids to choose the order of food consumption.
- Introducing new foods in small amounts without pressure.
- Avoiding the pressure of cleaning plates to help children learn to listen to their hunger cues.

Definition and Statistics:
- Up to 45% of children display problematic eating behaviors; can manifest as pickiness or disinterest in food.
Feeding Disorders:
- Oral motor difficulties affect many children (e.g., those with Down syndrome or cerebral palsy) and impact their ability to eat normally.
- Interventions may include therapy for increased coordination in feeding.
Extreme Selectivity in Feeding:
- Common in children with autism; often correlated with sensory sensitivities complicating dietary habits.

Example of Malnutrition and Selectivity:
- A child restricted to a diet of purely commercial pureed fruits and coconut juice led to severe health complications, including irritability, anemia, and low energy.
- Treatment required nutritional intervention and behavioral therapy to expand dietary intake.

Prevalence:
- Approximately 25% of Canadian children are overweight, mainly due to poor diet and low physical activity related to lifestyle changes.
Risk Factors:
- Genetic predispositions and environmental influences such as over-eating encouraged by marketing targeted towards children.

Leading Cause of Death:
- Car accidents rank as the most common cause of death for children over one year of age.
Parental Interventions for Safety:
- Ensuring proper safety equipment (car seats, helmets) and supervision during hazardous activities.

Infant Mortality Rates:
- Globally, around 10 million children under 5 die each year, primarily from preventable causes including malnutrition, diarrhea, and diseases like malaria.
Access to Healthcare and Vaccinations:
- Immunization trends are declining in some Western countries, further exacerbating the issue of preventable diseases.

Definition:
- Synaptic pruning is the biological process where excess neurons and synapses are eliminated to enhance neural efficiency.
Consequences of Over and Under Pruning:
- Too much pruning leads to conditions such as Alzheimer's, while insufficient pruning contributes to developmental disorders like autism.

Functional Brain Areas:
- Brain functions are distributed across specific areas, including motor functions and sensory processing located in the brain's cortex.
Adolescent Brain Development:
- Gray matter diminishes while white matter increases during adolescence, improving cognitive function through myelination.

Early Specialization:
- Brain regions specialize early in life for functions such as language and processing sensory input.
Acquisition of Specificity:
- The brain refines its processes for specific stimuli over time.
Different Rates of Development:
- Sensory and motor functions mature before higher-order functions.
Interaction with Environment:
- The brain develops based on regular environmental input that is expected at early ages.
Plasticity and Flexibility:
- Brain regions can adapt and recover from injury, although this capability decreases with age due to pruning.

Emphasizes the importance of understanding growth mechanisms (timing, nutrition, safety, and healthy eating habits) in ensuring optimal physical and cognitive development in children.
Acknowledges that early intervention, parental support, and educating children on nutrition can mitigate many challenges related to growth and development.