Puberty, Health & Biological Foundations PDF

Puberty, Health & Biological Foundations CHAPTER 2  CH 2 Outline Identify and distinguish between the physical determinants & key characteristics of puberty Examine the phases of puberty & psychological dimensions - including gender differences Sum...

Puberty, Health & Biological Foundations CHAPTER 2  CH 2 Outline Identify and distinguish between the physical determinants & key characteristics of puberty Examine the phases of puberty & psychological dimensions - including gender differences Summarize the nature of adolescent & emerging adults’ health issues (including risk-taking behaviors, access to health services, nutrition, exercise, sports, & sleep) Explore different perspectives on the influence that genetics & environment have on development  What is Puberty? A period of rapid physical maturation Involves hormonal & bodily changes Marks the beginning of adolescence  Determinants of Puberty Heredity ★ Pre-programmed genetically ○ Typically takes place between 9 -16 years old ★ Still studying the specific genes involved ★ Environmental factors do influence genetic expressions ○ (timing, intensity, etc)  Determinants of Puberty Hormones: Chemicals (biological messengers) secreted by the endocrine glands and carried through the body by the bloodstream How the brain impacts puberty ○ Androgens - main class of male hormones Testosterone ○ Estrogens - main class of female hormones Estradiol  Determinants of Puberty Hypothalamic-Pituitary-Gonadal Axis Hypothalamus: Regulates appetite, thirst, sexual drives & other bodily functions (temp. etc) Pituitary Gland: “Master Gland” - signals other glands into action; regulates growth Gonads: Regulate ovaries & testes  Hypothalamic-Pituitary-Gonadal Axis The Hypothalamus secretes the GnRH (gonadotropin-releasing hormone) - regulates pubertal timing Signals Pituitary Gland to release: ○ FSH (Follicle-Stimulating Hormone) starts follicle development/sperm production ○ LH (Luteinizing Hormone) Regulates estradiol production in females Regulates testosterone production in males  Phases of Puberty Adrenarche: Developmental stage before puberty “Awakening of the Adrenal Glands” - Stimulates hair growth (armpits, pubic), sweat production, acne and mood swings Gonadarche: Signals the onset of puberty Growth of ovaries & testes/increase in sex hormones Menarche - start of first menstrual period Spermarche - first ejaculation Pubertal Changes - Females Pubertal Changes - Males  EARLY Onset of Puberty - Factors Weight & Body Fat Higher weight/BMI ○ Reproduction requires energy! Sociocultural & Environmental Factors Developed/Urban areas & Stressful environments ○ Stress/Lack of Control = may trigger early onset as protective survival mechanism  Psychological Aspects of Puberty Early & Late Maturation Being an early-maturing male is advantageous as compared to being late-maturing (initially) ○ Berkeley Longitudinal Study - found late-maturing males had more positive identity in their 30s than early-maturers ○ WHY? Could not just rely on looks/physical abilities to define themselves, concerned more about academics, career choices, etc. Early-maturing girls are more vulnerable to a # of problems… ○ WHY? Immature person walking around in mature body…  Psychological Aspects of Puberty Body Image Adolescents are often preoccupied with their bodies in puberty ★ Girls = more body fat - lower body image ★ Boys = more muscle mass - higher body image Health Issues in Adolescence & Emerging Adulthood  Adolescence as a Critical Juncture in Health Adolescence = behaviors relevant to health are adopted ○ Behaviors linked to poor health/early death begin in adolescence ○ Adolescents are typically at their peak performance (health-wise, energy-wise, ability-wise) and may not appreciate the need to be health-conscious How to get teens to be healthier? ○ Don’t tell them what to do!!! ○ Treat with respect; give them information & options; let them make choices  Risk-Taking Behavior Adolescents seek experiences that create high intensity feelings ○ Steady increase from 11 yrs - late adolescence (peak at 19 yrs) ○ Cognitive “Culprits” - Prefrontal Cortex, Nucleus Accumbens, Amygdala ○ How Teenagers' Brains are Wired Differently Protective Factors: ★ Higher “social capital” - schools, community resources, neighborhoods ★ Better grades & communication skills ★ Parental monitoring Risk Factors: ★ Unstructured & unsupervised environments  Access to Health Services Adolescents under-utilize health-care systems ○ Lack of preventative care (only 38%) H.S. males = lowest rates H.S. & college females = highest rates ○ Barriers to health care Cost, availability, confidentiality concerns, reluctance of providers to honestly discuss sensitive issues with youth  Leading Causes of Death of Adolescents & Emerging Adults Unintentional injuries/Accidents Homicide Suicide Emerging Adults have twice the mortality rate of adolescents  Nutrition Nutrition is an important aspect of health- compromising vs health-enhancing outcomes US youth = POOR nutrition overall! ★ Eat more fried foods/fast food, skip breakfast, caffeinated/energy drinks, eat between meals, don’t eat enough fruits/veggies, eat in front of screens Family matters! ★ Availability & parent consumption of healthy foods ★ Eating family meals together = better health outcomes  Exercise Individuals become less active as they reach & progress through adolescence (increase to age 13, then decrease to 18) What factors influence exercise among adolescents? Parents Peers Screen time Physical education at school Benefits of regular exercise: Lower levels of substance use, depressive symptoms, stress Higher cognitive functions (memory, attention, etc) Better mood and potentially better sleep  Sports Positive effects: Negative effects: Less likely to engage in ★ Pressure from parents and risk-taking behaviors coaches ★ Competition anxiety and self- Positive self-identity centeredness Higher self-esteem ★ Academic performance can suffer ★ The use of performance- Less likely to be obese enhancing drugs Lower cardiovascular risk ★ Injuries  Sports Female athlete triad - condition based on the combination of: ○ Disordered eating ○ Amenorrhea - no menstrual period ○ Osteoporosis - low bone density Often is unnoticed by coaches, trainers, parents Higher risks of fractures & long-term bone density loss Can be treated with change in diet, exercise routine & hormone replacement therapy  Sleep Inadequate sleep is linked to several negative outcomes: ○ Lower academic performance, information- processing abilities, quality of peer relationships & higher levels of mood, emotional & substance abuse problems WHY are adolescents/emerging adults getting enough sleep? ○Delay in Melatonin release ○Too much screen time ○Too much caffeine ○Too early school start times ○Overscheduled Perspectives on Role that Genetics & Environment Play on Development  Evolutionary Psychology Emphasizes the importance of adaptation, reproduction & “survival of the fittest” Humans require time to develop a large brain and learn the complexity of human social communities = ADOLESCENCE! Based on concept of Natural Selection The evolutionary process that favors those individuals of a species who are best adapted to survive and reproduce. Focuses on Adaptive behavior Modification of behavior that promotes an organism’s survival in the natural habitat  Human Behavior Genetics Field that seeks to discover the influence of genetics and environment on individual differences How can we study to what extent people differ because of differences in genes, environment, or a combination of the two? Twin Studies ○ Compare Identical & Fraternal ○ Twins raised apart or together Adoption Studies: ○ Compare Biological relatives compared w Environmental ones  Heredity-Environment Correlations - An individual’s genes influence their environments Passive Evocative Active A child inherits A child inherits A child seeks out genetic tendencies genetic tendencies environments that from parents that naturally elicit naturally –AND– certain reactions match/compliment from those in their their inherited genetic The parents place environment tendencies the child in environments that match/compliment those tendencies  The Epigenetic View Development is the result of ongoing, bidirectional interchange between genetics & the environment Changes in the environment can trigger or depress/repress the expression of genes The expression of certain genes can be passed down to future offspring Can your environment affect your DNA?  Gene (x) Environment Interaction: The study of the interaction between a specific gene with a specific environmental condition Expression of Gene 5-AHTTLRP (+) Experiencing a stressful event (=) HIGHER chance of Depression