Adolescence Flashcards
(56 cards)
Hormonal changes
During middle childhood, the proportion of fat in the body gradually increases, and once a threshold level is reached, a series of chemical events is triggered beginning in the hypothalamus, a bean-sized structure located in the lower part of the brain.
These events lead the ovaries (in girls) and testes (in boys) to increase their production of the sex hormones. There are two classes of sex hormones, the oestrogens and the androgens. With respect to pubertal development, the most important oestrogen is oestradiol and the most important androgen is testosterone.
By the mid-teens, oestradiol production is about 8 times as high in females as it was before puberty, but only about twice as high in males. In contrast, testosterone production in males is about 20 times as high by the mid-teens as it was before puberty, but in females it is only about 4 times as high.
Primary sex characteristics
The production of ova (eggs) in females and sperm in males.
Females are born with all the ova they will ever have, around 300,000 ova by puberty. Once a girl reaches menarche (her first menstrual period) and begins having menstrual cycles, one egg develops into a mature egg, or ovum, every 28 days or so. Females release about 400 ova in the course of their reproductive lives.
males have no sperm in their testes when they are born and they do not produce any until they reach puberty. However, beginning with their first ejaculation (called spermarche), males produce sperm in astonishing quantities. There are between 100 and 300 million sperm in the typical male ejaculation, which means that the average male produces millions of sperm every day.
Secondary sex characteristics
The other bodily changes resulting from the rise in sex hormones during puberty, not including the changes related directly to reproduction. The secondary sex characteristics are many and varied, ranging from the growth of pubic hair to a lowering of the voice to increased production of skin oils and sweat.
Brain development
It has long been known that by age 6 the brain is already 95% of its adult size.
A sharp increase in synaptic connections occurs around the time puberty begins (10–12 years), a process called overproduction or synaptic exuberance. Overproduction of synaptic connections occurs in many parts of the brain during adolescence but is especially concentrated in the frontal lobes.
Between the ages of 12 and 20, the average brain loses 7–10% of its volume through synaptic pruning. Myelination was previously thought to be finished prior to puberty but has now been found to continue through the teens.
The cerebellum is part of the lower brain, well beneath the cortex, and has long been thought to be involved only in basic functions such as movement. Now, however, research shows that the cerebellum is important for many higher functions as well, such as mathematics, music, decision making and even social skills and understanding humour. It also turns out that the cerebellum continues to grow through adolescence and well into emerging adulthood. It is the last structure of the brain to stop growing, not completing its phase of overproduction and pruning until the mid-20s.
Timing of puberty
On average, girls begin puberty 2 years earlier than boys.
Among the Kikuyu, a culture in Kenya, boys show the first physical changes of puberty before their female peers, a reversal of the Western pattern.
Variation occurs between cultures and different developments occur inconsistently.
Given a similar cultural environment, variation in the order and timing of pubertal events among adolescents appears to be due to genetics. The more similar two people are genetically, the more similar they tend to be in the timing of their pubertal events, with identical twins the most similar of all.
Culture and the timing of puberty
Culture includes a group’s technologies, and technologies include food production and medical care. The age at which puberty begins is strongly influenced by the extent to which food production provides adequate nutrition and medical care protects health throughout childhood.
There is a steady decrease in the average age of menarche in Western countries from the mid-19th to the late-20th century. This kind of trend in a population over time is known as a secular trend.
The average age of menarche is lowest in developed countries (currently about 12.5 years old). In contrast, menarche takes place at an average age as high as 15 in developing countries.
Social and personal responses to pubertal timing
A great deal of research has been conducted on early versus late maturation among adolescents in the West, extending back over a half century. The results are complex: they differ depending on gender, and the short-term effects of maturing early or late appear to differ from the long-term effects.
Findings from a variety of Western countries concur that early-maturing girls are at risk of numerous problems, including depressed mood, negative body image, eating disorders, substance use, delinquency, aggressive behaviour, school problems and conflict with parents.
Early-maturing boys tend to have more favourable body images and higher popularity than other boys. One study that followed early-maturing adolescent boys 40 years later found that they had achieved greater success in their careers and had higher marital satisfaction than later-maturing boys. Like their female counterparts, early-maturing boys tend to become involved earlier in delinquency, sex and substance use.
Late maturing boys also report problems of higher rates of alcohol use and delinquency and lower grades. Late developing girls have relatively fewer problems.
Puberty rituals
Alice Schlegel and Herbert Barry analysed information on adolescent development across 186 traditional cultures and reported that 68% had a puberty ritual for boys and 79% had such a ritual for girls.
A qualitative study examining menstruation-related practices in Fiji, the Solomon Islands and Papua New Guinea found four main themes: (1) menstrual blood is ‘dirty’; (2) menstruating girls and women can bring ‘bad luck’ to men; (3) there is a certain amount of shame and secrecy around menstruation, and (4) these types of beliefs have an impact on health and wellbeing. Menarche is often believed to possess special power.
Female circumcision in adolescence, which involves cutting or altering the genitals, remains common in Africa, with rates of over 70% in many countries and above 90% in Mali, Egypt, Somalia and Djibouti.
Eating disorders
Girls are more likely to pay more attention to food once they reach adolescence and worry more about eating too much and becoming overweight . A 2015 national survey of Australian youth found that 37% of girls were either very concerned or extremely concerned about body image, compared to 13% of boys.
Dissatisfaction can lead adolescents to exhibit disordered eating behaviour. Disordered eating has negative impacts on a person’s physical and mental health, and includes less severe and frequent behaviours and attitudes typically found in eating disorders, such as restricting eating (i.e., fasting), compulsive eating (i.e., avoiding a food group) or irregular eating patterns.
The two most common eating disorders are anorexia nervosa (intentional self-starvation) and bulimia (binge eating combined with purging [intentional vomiting]). Approximately 4% of the Australian population are estimated to have an eating disorder.
Bulimia 1%
Anorexia 0.3%
Anorexia
Anorexia is characterised by four primary symptoms: inability to maintain body weight at 85% or more of normal weight for height
fear of weight gain
lack of menstruation
distorted body image.
One of the most striking symptoms of anorexia is the cognitive distortion of body image.
Bulimia
They engage in binge eating, which means eating a large amount of food in a short time. Then they purge themselves; that is, they use laxatives or induce vomiting to get rid of the food they have just eaten during a binge episode. People with bulimia often suffer damage to their teeth from repeated vomiting (because stomach acids erode tooth enamel).
Unlike those with anorexia, people with bulimia typically maintain a normal weight because they have more or less normal eating patterns in-between their episodes of bingeing and purging. Another difference from anorexia is that people with bulimia do not regard their eating patterns as normal. They view themselves as having a problem and often hate themselves in the aftermath of their binge episodes.
Treating eating disorders
About two-thirds of people treated for anorexia in hospital programs improve, but one-third remain chronically ill despite treatment.
An evaluation of different treatments conducted by Australian researchers concluded that family-based therapy (which included the family helping the young person to regain weight) was an effective approach for young people with anorexia.
Similarly, although treatments for bulimia are successful in about 50% of cases, there are repeated relapses in the other 50% of cases, and recovery is often slow.
Adolescents and emerging adults with a history of eating disorders often continue to show significant impairments in mental and physical health, self-image and social functioning even after their eating disorder has faded. About 10% of those with anorexia eventually die from starvation or from physical problems caused by their weight loss, one of the highest mortality rates of any psychiatric disorder.
Substance use
In Australia, tobacco smoking is decreasing in adolescents, with 97% of those aged 14–17 being non-smokers. More adolescents (around 73%) are also abstaining from alcohol.
Similarly, 10% of adolescents aged 14–17 admit to recently using illicit drugs, which is down from 23% since 2001.
Young people use substances for a variety of purposes, which can be classified as experimental, social, medicinal (self-medicated) and addictive.
Piaget’s theory of formal operations
Begins at about age 11 and reaches completion somewhere between ages 15 and 20.
Learn to think systematically about possibilities and hypotheses.
It also includes the development of abstract thinking, which allows adolescents to think about abstract ideas such as justice and time and gives them the ability to imagine a wide range of possible solutions to a problem, even if they have had no direct experience with the problem.
Hypothetical-deductive reasoning
The stage of formal operations involves the development of hypothetical-deductive reasoning, which is the ability to think scientifically and apply the rigor of the scientific method to cognitive tasks.
Critiques of Piaget’s theory of formal operations
The limitations of Piaget’s theory of formal operations fall into two related categories: individual differences in the attainment of formal operations and the cultural basis of adolescent cognitive development.
In adolescence and even in adulthood, a great range of individual differences exists in the extent to which people use formal operations.
On any given Piagetian task of formal operations, the success rate among late adolescents and adults is only 40–60%, depending on the task and on individual factors such as educational background.
Information processing: selective attention and advances in memory
One study found that watching television interfered with adolescents’ homework performance but listening to music did not.
Memory also improves in adolescence, especially long-term memory. Adolescents are more likely than younger children to use mnemonic devices.
Studies of executive functioning indicate that performance continues to rise past adolescence, well into emerging adulthood, peaking at around age 25.
Metacognition
Cognitive development in adolescence includes the development of metacognition, which is the capacity to think about thinking.
Adolescent egocentrism
Type of egocentrism in which adolescents have difficulty distinguishing their thinking about their own thoughts from their thinking about the thoughts of others.
According to Elkind, adolescent egocentrism has two aspects—the imaginary audience and the personal fable.
The imaginary audience
The imaginary audience results from adolescents’ limited capacity to distinguish between their thinking about themselves and their thinking about the thoughts of others. Because they think about themselves so much and are so acutely aware of how they might appear to others, they conclude that others must also be thinking about them a great deal.
The personal fable
Adolescents’ belief in the uniqueness of their personal experiences and their personal destiny is known as the personal fable.
The personal fable can be the source of adolescent anguish, when it makes them feel that ‘no one understands me’ because no one can share their unique experience.
It can be the source of high hopes too as adolescents imagine their unique personal destiny leading to the fulfilment of their dreams. Can also contribute to risky behaviour and sense of invincibility.
Schools: secondary education
In the Growing Up in Australia study, 15% of children said they experienced difficulties with the transition to secondary school, with making friends and missing old friends from primary school being the most common issues faced.
In the year before secondary school, children who scored lower on standardised tests in numeracy and who experienced more behavioural and emotional problems were more likely to report transition issues.
Virtually all adolescents are enrolled in secondary school in developed countries. In contrast, in many developing countries only about 50% of adolescents attend secondary school.
Approximately 84% of Australian high school students will remain full time from the start to the end of high school, although the retention rate of Indigenous students is 60%.
In maths and science, Japan and South Korea are consistently at the top.
In adolescence as at earlier ages, Eastern schools focus almost exclusively on rote learning (memorising information through repetition), whereas Western schools place more emphasis on promoting critical thinking and creativity.
European variations in secondary schooling
About half of adolescents attend a college-preparatory school that offers a variety of academic courses. The goal is general education, rather than training for any specific profession. About one-quarter of adolescents attend a vocational school, where they learn the skills involved in a specific occupation such as plumbing or auto mechanics. Some European countries also have a third type of secondary school, a professional school, devoted to teacher training, the arts or some other specific purpose. About one-quarter of European adolescents usually attend this type of school.
Adolescent work in developed countries
Most studies find that up to 10 hours a week working at a part-time job has little effect on adolescents’ development.
However, beyond 10 hours a week, the more adolescents work, the lower their grades, the less time they spend on homework, the more they cut class, the more they cheat on their schoolwork, the less committed they are to school and the lower their educational aspirations.
Boys were 60% less likely to finish Year 12 if they worked more than 15 hours.
Adolescents who work are also more likely to use alcohol, cigarettes and other drugs, especially if they work more than 10 hours a week.
Central and Northern European countries more likely for apprenticeship.
