CHAPTER 4: Growth & Health Flashcards
what percent of our lifespan does the human body grow
20%
boys achieve half their adult height by two years, 18 months for girls
proximodistal trend
- center of body outward
- head, chest and trunk first, followed by arms and legs and then hands and feet
example: If you throw a ball at a three-year-old, she will try to trap it with her arms, whereas older children will be more adept at using their hands to catch the ball.
cephalocaudal trend
- head to tail, development
- general maturation from head to foot
secular trends
marked changes in physical development that have occurred over generations
- height, onset of mensuration
- girls have a faster maturation than most boys
breastfeeding
- best way to ensure babies get nourishment needed
- contains proper amounts of minerals and vitamins
- can be breastfed until age 2
- exclusively for 6 months then introduce solid food
benefits of breastfeeding
- dont get as sick as often
- antibodies that kill bacteria and viruses
- lower risk for infections
- transition to solid food easier
- cant be contaminated
formula fed infants
- not harmful, when prepared properly provide same amount of nutrients
- more prone to allergies
- families can participate
fisher and birch (1999)
- Restricting access to foods focuses children’s attention to them and desire to eat them
- Using treats as bribes (to eat healthy foods) tends to make children like healthy foods less
causes of obesity
Heredity: genes affect individuals’ susceptibility to gaining weight, and also affect people’s impulsivity. Children with poorer impulse control and difficult temperaments tend to gain weight faster, have higher BMIs, and choose foods that lead to obesity.
Lack of activity
Lack of sleep: children who get less sleep are more prone to obesity, as they have slower rates of metabolism; lack of sleep also causes an imbalance in the hormones that tell us when to start and stop eating.
Lack of access to health foods
protective factor: eating together as a family
It’s been found that eating together as a family, at the table (as opposed to in front of the TV) is associated with healthier eating habits
what is the #1 cause of deaths in children over the age of 1
accidents - most common: car and bicycle accidents
-other: drowning, suffocating, falling
body mass index (BMI)
adjusted ratio of weight to height
- BMI scale is the basis on technical definition for being overweight
- children and adolescents in the upper 5% are overweight
- 18% of adults are obese
- obese children become obese adults
obesity in children
- in US, number of overweight children has doubled, and overweight adolescents
tripled - childhood overweight and obesity are more prevalent in Indigenous Peoples
- Approx 13% of Canadian children & teens
- Causes: overconsumption of high-fat, surgery foods
growth hormone
hormone secreted by pituitary gland during sleep regulates growth by triggering release of hormone somatomedin in liver that cause muscles
and bones to grow
puberty
collection of physical changes that marks the onset of adolescence; growth spurt and sexual
maturation
- girls begin growth spurt about two years earlier than boys
primary vs secondary sex characteristics
primary: – changes in bodily organs directly involved in
reproduction that are signs of physical maturity
secondary: signs of maturity in body parts not directly linked to reproductive organs (growth of breasts, facial hear, change in voice)
menarche and spermarche
onset of mensturation, age 13: early menstrual cycles are usually irregular and without ovulation
spermarche: first spontaneous ejaculation of sperm-laden fluid, age 13
experience dependent process
Initiated in response to experience
- those that unfold in a manner unique to the environment one is raised in
E.g. brain of musician vs. brain of athlete
experience expectant process
Under genetic controls, occur in any environment
E.g. evolution of visual cortex
- occurs naturally as parents offer babies age-appropriate play materials
plasticity
- High degree of plasticity in cerebral cortex during early childhood
- Children better able to recover from brain damage than adults
pituitary gland
- regulates physical development through release of growth hormone
girls: releases estrogen
boys: releases testosterone
osteoporosis
disease in which bones become thin and brittle, and can sometimes
break
- women are 5x more likely than men
- can be rooted in child and adolescence
rate of maturation
Early Male:
Positive self image
Antisocial behavior
positive/negative
Early Female:
Emotional problems
Low self-esteem
Antisocial behaviors
Eating disorders
Negative
Late Male:
Low self esteem
Feelings of inadequacy
Negative (at first)
Late female:
Self confident
Positive body image
Positive
girls and boys - calories
Girls:
13-15 need approx 2200 calories /day
16-19 2100 calories / day
Boys:
13-15 2800 calories /day
16-18 3200 calories /day
malnutrition
inadequate nutrition that causes one to be smaller for age
- worldwide 1 in 3 children under age 5 suffer
- 1 in 7 Canadian children lives in poverty
anorexia nervosa
disorder marked by persistent refusal to ear and irrational fear of
being overweight
bulimia nervosa
– disorder where individuals alternate between binge-eating, and purging through self-induced vomiting or laxatives
growth in brain size as a result of:
- neuronal connections
- synaptogenesis
- myelination
cerebral cortex
processing centre for:
- perception of patterns, execution of complex motor sequences, planning and decision making
body dysmorphic disorder
individuals are not satisfied with their body shape or
shape of a particular part of the body
- more common in boys
lateralization
- left and right hemispheres develop specialities
- starts during prenatal period
there is a high degree of _______ in the cerebral cortext during early childhood
plasticity
adolescent turmoil
- conflicts with parents
- mood instability
- risky behaviour
(confined to a minority of approx 20% of teens)
melatonin
- shifts sleep schedules
- deprivation negatively affects behaviour control, emotion and attention
depression in adolescents
- most common psychological disturbance among adolescents
Emotional symptoms: dejection, anhedonia
Cognitive symptoms: pessimism and hopelessness
Motivational symptoms: apathy, boredom
Physical symptoms: change in appetite, sleeping patterns
gender differences in depression
after puberty girls are more likley to be depressed:
- gender roles
- increased levels of stress
- sensitivity to others
prior to adolescence: boys are more likely
suicide
2nd highest cause of death for Canadian youth ages 15-24 (approx, 300 deaths/year)
10% girls & 5% boys make attempts serious enough to require treatment; boys more likely to engage in fatal suicide behaviour
risk factors: depression, family history, extreme stress
most common substance uses
- alcohol
- cannabis
- e cigarettes (vapes)
treatments for eating disorders
- hospitilization
- indidivudal or family psychotherapy
- CBT
- antidepressants
brain development in adolescence
changes in:
- prefrontal cortext (logic, reasoning)
- limbic system (emotion)
- can lead to risky behaviour (impulsive, invulnerbility, overconfidence, peer influence)
amygdala
part of limbic system in mature brain responsible for processing emotional and motivational stimuli
o important for social-emotion processing
o recognize emotions and facial expressions
