This preview shows page 1. Sign up to view the full content.
Unformatted text preview: Overview of Physical Development in Overview of Physical Development in PreAdolescence and Adolescence Dr. Leilani Brown The End of Childhood A product of both biological and social forces Early Adolescence: 11 to 14 years, a period of rapid pubertal change. Middle Adolescence: 14 to 16 years, when pubertal changes are nearly complete. Late Adolescence: 16 to 18 years, when young people are considered emerging adults. Concepts of Adolescence Concepts of Adolescence Current research shows that adolescence is not a purely biological event. Storm and stress are not universal aspects of adolescence. Adolescence is now viewed as a product of both social and biological factors. Brain Development in Pre Brain Development in Pre Adolescence and Adolescence During puberty, synaptic pruning continues at a slower rate while myelination accelerates. The brain functions more efficiently. Reactivity to positive and stressful events is more pronounced. Changes occur in the way the brain times sleep cycles; sleep deprivation can be a problem. The amygdala, which acts as an emotional filter for memory, affects all learning, and is especially powerful in young adolescents The Onset of Puberty The Onset of Puberty Hormonal changes which began in middle childhood initiate puberty. Puberty arrives approximately two years earlier for girls than for boys. First outward sign is a rapid growth spurt in height and weight. The cephalocaudal trend reverses and lengthening of the torso is responsible for most of the height gain. Three Phases of Puberty Three Phases of Puberty Prepubertal: Before age 13 in boys and before 11 in girls. Its duration for boys is approximately 1518 months, and for girls it is slightly shorter. Pubertal: occurs between 13 and 15 for boys and 11 and 14 for girls and includes a dramatic growth spurt. Postpubertal: follows the menarche, the first menstrual period for girls, and semenarche, the first nocturnal ejaculation for boys. Benefits of Puberty Benefits of Puberty Improvements in gross motor performance. Boys experience larger gains than girls. Physical activity and sports are a good option at this time. In the USA and Canada, unfortunately, fewer adolescents are participating in sports. The Biochemistry of Puberty The Biochemistry of Puberty Puberty is initiated by hormonal changes triggered by the hypothalamus, which stimulates the pituitary gland, which in turn activates other glands. The balance of the male hormone testosterone and female hormone estrogen, which are present in all children, changes at puberty. Girls produce more estrogen and boys produce more testosterone. The Feedback Loop The Feedback Loop that Regulates Puberty Throughout puberty, the hormones, organs and the bloodstream communicate through a biological feedback loop (Emanuele et. al, (Emanuele et. al, 2003) Oh, those Sex Hormones! Oh, those Sex Hormones! Sex hormones regulate changes in primary and secondary sex characteristics. Menarche occurs late in the girl’s sequence of pubertal events. Girls in conflict ridden families and obese girls reach menarche earlier. Improved physical health and nutrition has led to a secular trend toward earlier menarche in developed nations. Pubertal Changes for Boys Pubertal Changes for Boys Boys experience enlargement of the body, shoulders, and sex organs. Underarm, facial, body, and pubic hair appears. Spermarche takes place. A height spurt occurs between 13 and 15 years. Voice “changes” and deepens. A peak strength spurt appears between 13 and 17 years. Pubertal Changes for Girls Pubertal Changes for Girls Girls add more fat, while boys add more muscle to their bodies at this time. Menarche occurs. Breasts enlarge and pubic and underarm hair appears. Hips broaden and a height spurt begins. A peak strength spurt occurs at about 12 years. Location, Location Location, Location Boys who live in areas where there is war, poverty, and little food are likely to be shorter than their genetic potential. Girls who live in hot geographical regions close to sea level and with a high caloric diet have their menarche earlier than girls who live in high, cold climates and have restricted caloric diets. Windows of Opportunity Windows of Opportunity During late childhood, there appears to be a window of opportunity related to the pubertal growth spurt. Youth in late childhood who have been malnourished and are delayed in their growth in height can actually grow very quickly with nutritional intervention and sometimes catch up to their own potential. Health Issues Health Issues Nutritional requirements increase. Many adolescents suffer from vitamin and mineral deficits. Girls are at high risk for eating disorders. Motor vehicle collisions are the leading cause of injury and death at this time. Increased sex drive and increased feelings of invincibility lead to sexual risk taking. Did You Know? Did You Know? HPV is a sexually transmitted virus that causes cancer and genital warts in females. Gardasil is a vaccine specifically designed to prevent cancer related to HPV. The USDA Advisory Committee on Immunization Practices recommended that 11 and 12yearold girls be routinely vaccinated against HPV. Adolescent Pregnancy Sexually active adolescents in the USA are less likely to use contraceptives than their counterparts in other developed countries. 20 percent of American and 13 percent of Canadian sexually active adolescents are at risk for unintended pregnancy. Those with good relationships with parents and those who talk openly about sex and contraceptives are more likely to use them. Sexual Orientation Sexual Orientation About 3 to 6 percent of adolescents discover that they are gay or lesbian. Heredity is a factor in homosexuality. By the end of adolescence, the majority of gay and lesbian individuals have accepted their sexual identity. Nevertheless, suicide attempts are unusually high in gay, lesbian, and bisexual young people. Eating Disorders: Anorexia Eating Disorders: Anorexia Nervosa Compulsive starvation for fear of being fat. 1 percent of North American girls have anorexia. Cases have increased in the last century. Asian American, CaucasianAmerican, and Hispanic girls are at highest risk. In the attempt to reach “perfect slimness” anorexics lose between 25 and 50 percent of their body weight. Menstrual cycles stop. Brain, heart, and bone mass are damaged. 6 percent die of the disorder. Only 50 percent fully recover. Bulimia Nervosa Bulimia Nervosa More common than anorexia. Strict dieting, excessive exercise, followed by binge eating and vomiting. 2 to 3 percent of teenage girls are affected. Like anorexia, bulimia is influenced by heredity. Bulimics are aware of their abnormal eating habits and often seek treatment. Factors that Influence Eating Factors that Influence Eating Disorders Forces within the person, the family, and the larger culture contribute. Anorexia tends to run in families. Problem eating in early childhood is linked to anorexia. Poor body image and problems with autonomy also contribute. Treatment is more difficult for anorexia than for bulimia. Substance Abuse Substance Abuse In the USA and other modern countries, the use of alcohol, tobacco, and illegal, over the counter, and prescription drugs is widespread. Substance abuse in the USA accelerated in the 1990s and has decreased during the past few years. Media advertisement is an influential factor in adolescent alcohol, prescription drug use, and smoking. Improved parenting skills helps to reduce substance abuse in adolescents. An Exercise to Conclude: An Exercise to Conclude: What Do You Think? Flip through the pages of your favorite popular magazine. What is our society’s broad view of how young women should look? What is the male image for our society? Are these images healthy? How many ads for prescription drugs, tobacco, alcohol, and diet additives were in the magazine? ...
View Full Document
This note was uploaded on 04/08/2011 for the course FAMR 230 taught by Professor Brown,l during the Spring '08 term at University of Hawaii, Manoa.
- Spring '08