Puberty
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Puberty refers to the various changes that transform a child’s body into an adult one. A sequence of biochemical signals from the pituitary gland to the hypothalamus to the adrenal glands increases production of testosterone, estradiol, and various other hormones, which in turn cause the body to develop.
Hormones regulate daily and seasonal body rhythms. In adolescence, these may result in sleep deprivation because high schools open early and the natural circadian rhythm keeps teenagers wide awake at night.
Puberty can begin as early as age 8 and as late as 14, but most often begins between ages 10 and 13. Genes, gender, body fat, and family stress all contribute to this variation in timing, with girls generally beginning puberty before boys.
Adolescents who reach puberty earlier or later than their friends experience additional stresses. Early maturation may be especially difficult for girls, whereas culture and cohort influence how early or late maturation affects boys.
In the growth spurt, every part of the body grows rapidly. Peak weight usually precedes peak height, which is then followed by peak muscle growth.
Males and females develop differently at adolescence, not only in reproductive potential (primary sexual characteristics) but also in body shape, breasts, voice, body hair, and other secondary sexual characteristics.
Body image is a concern of many adolescents, who worry about how other people perceive them. They may diet irrationally instead of eating a balanced diet, which can often result in calcium and iron deficiency.
Although anorexia, bulimia, and binge eating disorder are not usually diagnosed until early adulthood, their precursors are evident during adolescence. The origins are genetic and familial as well as cultural.
Thinking, Fast and Slow
Various parts of the brain develop during adolescence. The regions dedicated to emotional arousal (including the limbic system) mature before those that regulate and rationalize emotion (the prefrontal cortex). Consequently, many adolescents are quick to react and take risks. Depending on specifics, this may be beneficial.
Cognition in early adolescence may be egocentric, a kind of self-
Formal operational thought is Piaget’s term for the last of his four periods of cognitive development, in which adolescents are no longer earthbound and concrete in their thinking. They prefer to speculate instead of focusing on reality. They develop hypotheses and explore, using deductive reasoning.
Intuitive thinking becomes stronger during adolescence, often overwhelming the analytic thinking that also develops. Few teenagers always use logic, although they are capable of doing so. Dual processing is evident.
Adolescents use technology, particularly the Internet (via smartphones, laptops, and tablets), more than people of any other age. This advances learning, including access to more information than was available a few decades ago. Stronger friendships and a wider social circle are additional benefits.
However, adolescents sometimes use cell phones and instant messaging for cyberbullying or sexting, both of which may be more harmful than senders realize. Adults have two other worries—
Teaching and Learning
Achievement in secondary education—
In middle school, many students tend to be bored, difficult to teach, and hurtful to one another. One reason may be that middle schools are not structured to accommodate egocentrism or social learning. Students’ beliefs about intelligence may also affect how much they study and pay attention.
Education in high school emphasizes formal operational thinking, sometimes to the detriment of applied cognition as measured by the PISA, an international test. In the United States, the demand for high standards has led to high-
Student cognitive needs in high school are diverse. Schools that accommodate every student combine personal attention and intellectual challenge.