Human Growth and Development Chapter 17 Early Adulthood: Biosocial Development PowerPoints prepared by Cathie Robertson, Grossmont College Revised by Jenni Fauchier, Metropolitan Community College

Growth, Strength, and Health Young adults are strong, healthy, and disease free

Men typically stronger than women For both sexes, physical strength increases until 30, then declines All body systems functioning at optimum levels Death from disease is rare –violent death more likely Norms and Peaks

Occurs when growth stops but ongoing throughout adulthood Physical decline related to age –varies markedly from person to person, organ to organ Organs: First visible changes are in skin--looses elasticity Graying hair and male pattern baldness begin around age 30 Variability in senescence appears Signs of Senescence

Gender Differences in Health and Senescence Appearance seems more important for women than for men –in some ways, women slower to become old –women generally healthier and have better health habits few fatal diseases, live at least 5 years longer than men, on average

Gender Differences in Health and Senescence, cont. Two ways females are at a health disadvantage –undernourishment –reproductive systems problems

Gender Differences in Health and Senescence, cont. Three explanations why twice as many women than men live to after age 80 –biological: protective evolutionary biology –cognitive: less risk taking –psychosocial: marriage, family life, friendship, and help-seeking are all protective of health, and women are more likely to engage in these

Body’s attempt to keep systems in balance —homeostasis –set point is affected by genes, diet, age, hormones, and exercise Aging makes it more difficult to recover from physical stress What a 20-year-old can do is more difficult for a 35-year-old Homeostasis

Reserve Capacity Bodies that are maintained adequately can have greater capacity to respond to stressful events or conditions –if not, our organ reserve capacity declines –organ reserve—extra capacity for responding to unusually stressful events or conditions that demand intense or prolonged effort

Reserve Capacity Serious reductions are not normally reached until late adulthood

Athletic performance peaks between ages 15 and 35 Within a sport, skills peak at different ages –super stars more likely to peak later Impact of aging on skills depends on lifestyle Sports Stars and the Rest of Us

Sexual Responsiveness Typical male sexual response –sexual arousal and excitement –orgasm –refractory period (time between responses) is short –overall slowing down over time

Sexual Responsiveness, cont. Typical female sexual response –sexual arousal and excitement and orgasm take longer than for men –from early adolescence to middle adulthood, arousal and orgasm become more likely

Sexual Responsiveness, cont. Explanations of male and female differences in sexual responsiveness –both partners learn to match timing in love making to prolong man’s excitement and intensify woman’s sexual responses –cultural men expected to be rapid in sexual response, and women to repress desire and emphasize control

Sexual Responsiveness, cont. Explanations of differences in sexual responsiveness, cont. –evolutionary psychology promiscuous males produce more offspring and pass on their genes more often, which is an evolutionary goal women reproduce and create safe haven for children

Peak time of fertility for women: before age 30; for men: before age 40 Between 2 percent and 30 percent of all couples experience infertility— average of 15 percent –infertility—failure to conceive after a year of intercourse without contraception Fertility

Fertility, cont. Male Infertility – 1/4 of cases related to sperm/sperm count Female Infertility –pelvic inflammatory disease may block fallopian tubes –endometriosis –infections, fibroid tumors uterine health affected by other health factors

Fertility, cont. Medical Advances –in vitro fertilization (IVF)—ova surgically removed, fertilized by sperm in lab, and allowed to divide until zygote reaches 8- or 16-cell stage –assisted reproductive technology (ART)— collective name of different technologies that aid in fertility

Emotional Problems in Early Adulthood Dieting Drugs Violence

Set point—particular body weight that an individual’s homeostatic process strives to maintain Dieting is common among girls, not unusual for boys One in 20 teenagers takes dieting too seriously and has an eating disorder Dieting as a Disease

Dieting as a Disease, cont. Culture and diet industry messages (via media) tell us to be thin so we will be happy and successful –almost 50 percent of women in North America have a BMI of less than 25, so they are not overweight at all –many young women connect self- concept with body image

Anorexia Nervosa Restriction of eating to the point of emaciation and possible starvation Four Symptoms –refusal to maintain body weight of at least 85 percent of normal weight for age and height –intense fear of gaining weight –disturbed body perception and denial of problem –in females, absence of menstruation

Bulimia Nervosa Repeated episodic binge eating followed by purging To be clinically diagnosed, –bingeing and purging must occur at least once a week for three months –the person must have uncontrollable urges to overeat –the person must show distorted self- judgment about body image

Theories: Eating Disorders Psychoanalytic: Women have conflict with mothers, cannot separate Behaviorism: For people with low self- esteem, bingeing and purging relieve states of distress and tension Cognitive: Women competing in business against men want to project masculine image

Theories: Eating Disorders, cont. Sociocultural: Women feel cultural pressure to be slender Epigenetic: Girls who are overwhelmed by development find that anorexia stops growth and decreases presence of sexual hormones

Drug Abuse and Addiction Drug addiction—physiological or psychological drive to ingest more of a drug –addiction begins with use Young adults more likely to be addicts

Drug Abuse and Addiction, cont. Marked gender, ethnic, and national variations in rates of drug addiction –men more likely than women –European Americans and Hispanic Americans more likely to use than are Asian-Americans or African Americans –English-speaking countries more likely to use drugs

Drug Abuse and Addiction, cont. College students particularly vulnerable –more to alcohol Social context encourages use and abuse –on their own –rock concerts –spectator sports –other group activities

Drug Abuse and Addiction, cont. Consequences of drug use often serious –avoid, drop out of, or flunk out of college –work below potential –lose or quit jobs –involved in transitory, uncommitted sexual relations –die violently –experience serious psychological difficulties

Many young adults struggle with serious emotional difficulties –12 percent experience at least one episode of depression, schizophrenia, or pathological rage made worse if using drugs or alcohol Psychopathology

Psychopathology, cont. Some difficulties may originate in childhood –parents abusive, neglectful, or erratic –death of mother or alcoholism of father Typically, childhood disturbances, biological problems, and environmental stress are all involved

Between ages 20 and 35, at least 15 percent of women and 8 percent of men suffer from at least one severe episode of depression Major depression is fueled biochemically –neurotransmitters –hormones Remission is likely with treatment that includes cognitive therapy and medication Depression

1 percent of all adults experience at least one episode of schizophrenia Caused by genes and severe early trauma such as anoxia at birth Medication seems to be most effective if person understands disease Schizophrenia

Violence In U.S., 1 male in every 100 between the ages of 15 and 25 dies violently –motor vehicle accident, homicide, or suicide Worldwide, young men more likely to die violently than women (especially between ages of 20 and 25) –4 times as many commit suicide –6 times as many are murdered –by nation or ethnic group, male-to-female ratio varies from 3:1 to 10:1

Violence, cont. Developmentalists suggest two reasons –biological—unlike females, in males, higher levels of testosterone correlate with impulsive, angry reactions –psychological—high self-esteem and dashed expectations more likely to result in violence in the presence of alcohol, a weapon, or lack of self- restraint