PSCI 112D - Psychosocial + Biological changes of puberty

Tanner stages

A system that describes the five stages of pubertal development.

What is the first sign of pubertal change among males and females?

Males: Testicles start to grow

Females: Breasts (or breast buds) start to grow

Menarche

The first time a female goes through menstruation. 

What is the sequence of pubertal changes among males? 

1. Growth of testicles, scrotum

2. Growth of pubic hair

3. Body growth

4. Growth of penis + Change in voice

5. Facial and underarm hair + acne

What is the sequence of pubertal changes among females? 

1. Growth of breasts

2. Growth of pubic hair

3. Body growth

4. Menarche

5. Underarm hair + oil and sweat-producing glands

Is puberty stressful for adolescents?

No, adolescents who struggle with puberty come from high-risk households and are more sensitive to external stressors.

What factors contribute to pubertal timing?

• Nutrition + Health

  • Individuals who are well-nourished likely to mature faster

• Genetics

• Social factors – Family conflict increases pubertal timing

Why do girls mature earlier than boys?

Girls are more vulnerable to the problems and stress of maturation (body image, appearance) which increase early maturation 

• Girls are more likely to deal with the stress of sexual harassment, bullying, and abuse from being relationships 

• Differences in cultural desirability of body types

What impact does early and late maturation have on girls? 

• Early maturation

  • More emotional difficulties which persist into adulthood (anxiety, depression, eating disorders)

  • High emotional arousal 

  • Poor self-image 

• Late Maturation

  • Less likely to engage in delinquent behavior 

What impact does early and late maturation have on boys?

• Early Maturation

  • High self-confidence

  • High temper

  • Likely to engage in alcohol and drug use 

    • Why? Younger boys not as close to supervised adults 

• Late Maturation

  • Emotional difficulties

Between males and females, which gender creates better coping skills during early maturation? Late maturation?

• Females create better coping skills during early maturation

• Males create better coping skills during late maturation

What changes happen to sleep patterns throughout adolescence?

• Adolescents tend to sleep later and wake up earlier

  • Delayed phase preference

Delayed phase preference

A pattern of sleep characterized by later sleep and wake up times, which usually emerges during puberty.

Why do adolescents sleep later?

• The time for adolescents’ melatonin levels rise changes and tend to rise later into the night

  • The biological aspects to sleep and puberty interact with environmental factors (screens at night, socializing, caffeine, nicotine, anxiety) – caused delayed phase preference 

REM Sleep

One of the stages of the sleep cycle where the brain goes through active changes, muscle relaxation and eye movement.

According to a study by Carskadon & Acebo (2002), the nighttime increase in melatonin starts about [blank] hours later among adolescents who have completed puberty than among those who have not yet begun.

2 hours

Why is sleep important during adolescence?

• Sleep helps repair the telomeres in our brain

• Sleep is essential to restorative functions and development of the body – physical recovery, emotional regulation, cognitive functioning

Why is REM sleep important?

• REM sleep helps activate parts of the brain that help regulate body functions (breathing, heart rate, body temperature)

• Supports memory consolidation

• Supports emotional regulation

Endocrine System

The system of the body that produces, circulates, and regulates hormones.

Kisspeptin

A brain chemical believed to trigger the onset of puberty

Leptin

A protein that tells our body when we have enough fat.

Puberty

The period of adolescence transitioning to sexual maturity. 

Adrenarche

The maturation in the adrenal glands – when puberty is first turned on. 

When does adrenarche start?

Around 9-10 years old

Why is the endocrine system essential to puberty/adolescence?

To regulate and monitor certain hormones from the central nervous system

Pituitary gland

The main gland in the endocrine system; facilitates growth and development

Gonads

Glands that secrete sex hormones. 

What are parts of the endocrine system and the hormonal feedback loop?

• Hypothalamus

• Pituitary glands

• Gonads

• Sex hormones (androgens and estrogens)

Melotonin

A hormone that contributes to sleepiness and the trigger of onset puberty.

What triggers pubertal maturation?

Kisspeptin triggers the onset of puberty, and is stimulated by the protein of leptin and melatonin in the body

Why is leptin important in puberty development?

• Leptin is needed to help the body regulate hunger and appetite

• Leptin is essential for women in order to develop the correct body weight to carry a child

What are the earliest stages that both genders fully go through puberty?

• Females: ~age 10

• Males: ~age 12

Describe the secular trend. What does this say about pubertal growth and development? 

The secular trend is the decline in the average age of menarche over time; due to improvement in nutrition, living conditions and better sanitation.

• Mostly documents girls not as much with boys

• Developing countries see more of a decline due to changes in living standards