adolescent midterm

what is adolescence and what does it describe?

A cultural phenomenon that describes the period when puberty begins and ends at adulthood

what ages is adolescents occurring?

Roughly ages 10-18 years, and perhaps extends to emerging adulthood (ages 18-25 years) as more individuals continue to depend on their parents for financial and/or emotional support

what % of the world’s population account for __% of the world’s income

20% of the world’s population account for 50% of the world’s income

how many children have no access to school (6-18)

235 millon

2019 data about math and literacy

Global literacy and mathematics have been on the decline as of 2019 data

• (44% have minimum proficiency in math, 24% can read)

___% of the worlds population has a smartphone, and what does it affect?

69%

• ncreasingly adolescents have bicultural identity—one to align with local traditions and practices, and one to align with their preferred online community

where was majority of empirical research on adolescence conducted?

the west, with a minority of adolescents in the world

does puberty began earlier now? why so?

• With better prenatal and early years care (healthcare, nutrition, parental awareness), puberty begins earlier than in the previous century

  

what type of construction is emerging into adulthood considered?

cultural construction

what’s the Criteria for adulthood

• Accepting responsibility for oneself

• Making independent decisions

• Being financially independent

• Cultural specifics: military service, supporting a family, supporting parents, marriage

  • Naturally, “adult” is a cultural contstruct

a scientific method breakdown

1. A curiosity: “Are smartphones bad for youth?”

2. Collect the evidence: “Who has smartphones, and how are those youths doing relative to those who don’t have smartphones?”

• Fine detail in methodology: do you want to compare those who have vs. have not, spend more time vs. less time, specific apps or just any smart phone activity...

1. Draw conclusions

   

2 types of data collection

collecting your own

relying on someone else’s

what do correlations examine?

the relationship between two existing variables

The experimental method

breakdown

hypothesis

testable hypothesis

create 2 groups (experimental and control)

dependant variable

indepdant variable

results

statistics in developed country for education

• All adescents obtain secondary education

• 50% tertiary education

 

statistics for education in a developing country

• 20% of adolescents do not complete primary school and only somewhat more than half enrolled in secondary

  • 80% do

• Tertiary education are only for the wealthy elite

who adheres most closely to the historical traditions of their culture

• Rural areas of developing countries, who tend to adhere more closely to the historical traditions of their culture than people in urban areas

  

• Traditional cultures tend to be more collectivist than other cultures, in part because in rural areas close ties with others are often an economic necessity

 

what is a majority culture?

• Sets most of the norms and standards and holds most of the positions of political, economic, intellectual, and media power

• Many minority cultures defined by ethnicity, religion, language, or other characteristics

Asias culture

• Filial piety

  • Children are obligated to respect, obey, and revere their parents, especially their father

• Asians are more likely to have a grandparent living in home then other cultures

  

indias culture

• 2010 education compulsory for children 6-10  to gain education

• Young pople, mainly girls are illiterate

latin americas culture

• Unemployment in young people is high, exceeding 25%

 

Endocrine system breakdown

• Hypothalamus signals hormonal changes

  • Gonadotropin-releasing hormone production increased (related to body fat)

  • Fat cells produce protein leptin that provides signal to release GnRH

• Pituitary Gland releases gonadotropins

  • Follicle-stimulating & luteinizing hormones

• Poor thyroid functioning related to abnormalities sexual development

feedback loop

sex differences in esterdil and testororsone

• Important to understand that estrogens and androgens exist in both sexes

• More sex-specific sex hormones are released as puberty progresses

  

growth spurts

• Typically not much difference in first years of life

• Fastest you grow at one

• Increase at puberty

• Difference plays a big role in difference of body image

  • Natural reason girls pay attention to physical appearance earlier

    • And throughout puberty

      

what many years ahead do girls start showing puberty signs

~2 years

male vs female wight gain?

males: major body muscle

females: fat

name primary sex characteristics

menarche: first period

spermarche: first production of sperm

menarche and ovulation

•  first menstrual period (mature egg released ~28 days; ~400 ova over lifetime, first 4 years ovulation is unpredictable)

  • Bleeding doesn’t always mean ovulation for the first 4 years

    

secondary sex charcteristics

• skin oil and sweat

• underarm hair

• change in voice

• growth spurt

• pubic hair

• breast development

what changes first in a females body

• breasts

• noticeable feature to all

classic BMI guidelines

• Canadian Guidelines (canada.ca)

  • Underweight: BMI < 18.5

  • Normal weight: 18.5-24.9

  • Overweight: 25-29.9

  • Obese: BMI ≧ 30

 

Issues with BMI index

• Not a direct measure of body fat, does not indicate body fat distribution, does not account for muscle mass (e.g., weightlifters will be considered to have too much fat when using BMI)

• BMI does not distinguish between men, women, nor different ethnicities (less accurate for non-White individuals)

define obesity

• Chronic, progressive, and relapsing disease, characterized by the presence of abnormal or excess adiposity that impairs health and social wellbeing

what is the prevalence of obesity in 1975 and 2016

 1% in 1975, 7% in 2016 (5-19 years of age; WHO))

is weight in youth increasing? both in developed and devilling countries?

yes

health risk of weight on adolescents

• Health risk: breathing, fractures, hypertension, insulin resistance

  • Insulin: hormone in pancreas that helps glucose in the blood to be metabolized as energy in muscle, fat, and the liver

what percent of adolescents in the US eat fast food daily

36%

gene and envoirnemtn role in obesity

• Hereditary and family concordance in obesity

  • E.g., correlation coefficients between husband & wife = 0.10-0.19; among siblings =0.24-0.34, DZ twins = 0.15-0.42, MZ twins = 0.70-0.88

• Different genes control protein synthesis and function involved in appetite, energy expenditure, metabolism, and adipogenesis

  • Genes respond to the environment

    • May burn more calories running then someone else

    • Controls hunger

    • If you enjoy exercise

• Impact of dietary fat on obesity prevalence is controversial (i.e., may impact carbohydrate & protein consumption, depends on genetic predisposition and physical activity)

 

environnemental impacts

Possible that environmental factors have the most impact during growth than after growth

 

puberty secular trends

• Menarche in Western countries has decreased in past 150 years

• Puberty begins earlier with good nutrition and medical care

• US = 12 years, some African countries could be 16 or 17

  • Environment where you live effects the time of puberty

    

what factors predicted early menarche

• Later born, urban residency (urbanization increasing, 1985: 24%, 1995: 29%, 2010: 50%), high BMI (predicted based on the role of fat on triggering hypothalamus activity)

• Hypothalamus is reaching a set point of adipose tissue on your body

• High carbohydrate intake predicted later menarche

• SES, household income, parental education, fat intake, exercise not correlated to early vs. late menarche

  • Dietary fat consumption - not correlated to early or late menarche

    

difference between rural and urban areas in puberty

• Some criss cross but overall city living more likely more earlier age than rural areas

• Less difference now than the 70s

  

what are endocrine disrupting chemicals?

• Synthetic chemicals in the environment that could impact the endocrine system and reproductive health

  • Impacts adults as well, but adolescents is particularly prone as its changing to be sexually mature

  • May mimic hormones, disrupt hormone synthesis or breakdown, alter development of hormone receptors, act as hormone antagonists, or alter hormone binding

    • Now working against it and body does not benefit

• Most common sources: pesticides, plastics, electronic wastes, flame- retardants, metals, food additives, personal care products

  

what is the evidence for exogenous chemicals onsetting early puberty?

• Evidence is mixed: varying degrees of exposure, timing of exposure, and non-linear dose-response patterns (i.e., incremental increase in exposure does not mean incremental earlier puberty)

  

oskihan

•  (red bean rice) is often cooked for any celebratory meal in Japan (e.g., accepted into university, first job, etc.)

• Historically, the mother cooked it for dinner when the daughter experienced menarche

• Not as common today

  

puberty rituals

• Most cultures have a ritual to celebrate the beginning of puberty

• For girls, menarche is usually the event that is celebrated

  • For some cultures menstruation is taboo and associated with restricting the woman’s behaviours, whereas in other cultures it is celebrated, and in some cultures there are ambivalent responses

• For boys, typically associated with age, and involves rituals that display courage, strength, and endurance

• Many cultures traditionally had rituals that involved pain, as initiation into adulthood and preparation for life’s challenges as an adult (e.g., Samoan tattooing especially painful for boys)

 

 

parent adolescent relations

Relations between parents and adolescents become cooler when pubertal changes become evident

what happens to self esteem in adolescents

declines

what did teens report for days with they experience maternal warmth and not conflict

higher self esteem

does maternal warmth effect long term

• Maternal warmth also associated with better self-esteem the next day (more long-lasting effects with warmth)

  

is puberty a taboo?

Menstruation and ejaculation (masturbation) have been taboo topics in many cultures, including North American culture

• The better informed the adolescents are, the more positive their experience towards the physical changes associated with puberty

  

what percent of girls have no knowledge of menarche before occurring?

60%

why is puberty a taboo to girls? and how to rural learn?

• Effort to keep girls “pure” and away from sexuality (rural girls learned about sex and reproduction through taking care of farm animals, but urban girls more sheltered)

  

spermachre and semanarche

• permarche: first production of sperm (no way to know yourself when)

• Semenarche: first ejaculation

  • Cultural differences in whether this is to be experienced privately or celebrated with others

  • No one measures when this happens

    

does the effect of enviornemtn increase or decrease with age?

• The effect of environment increases with age, such that adolescents and adults are less determined by their parental environment than infants and children

  

early studies reveal intelligence, specific cognitive abilities (e.g., memory), personality, and psychopathology, vary HOW much between and within families?

vary as much within families as between families

the better model for experience environment and genetics

• Genotype of parents —> Phenotype of parents —> Environment of child

• Genotype of parents —> Genotype of child —> Phenotype of child —> Environment of child

  

passive

evocative

active

• Passive: Biological parents provide your environment

• Evocative: Individual’s genes evoke specific responses

• Active: Individual’s genes seek out environments that match predispositions/tendencies

  

do people make their own expierences?

 people make their own environments, based on their own heritable characteristics

difference with moms to first and second borns

• Firstborn infants looked at their mothers and smiled more, and engaged in more exploration with objects than second born infants

• Mothers engaged in more physical encouragement, social exchange, didactic interaction, material provisioning, and language with firstborns than second borns

• Only feeding & holding did not differ between two infants

  

time with older and younger siblings??

• “time” is determined by age of older child (older child, less time), and then parent “splits” the time equally between two children

  • Time is determined by the age of the older child

    • Older child is 3 needing a lot of moms time

    • If there 12 there expected to play alone

• First-born child receives 20-30 minutes of quality time each day more than second-born child of same age

 

what personality trait is affected by birth order?

• onfirmed birth-order effects on intelligence: 1.5 points decline with increasing birth-order

• No birth order effects on extraversion, emotional stability, agreeableness, conscientiousness, imagination

  

Behavioural genetics research reveals that the environment impacts

---

---

---

traits more than _____

Behavioural genetics research reveals that the environment impacts psychological traits more than genetics

behavioural genetics 101

• Covariance among relatives on normally distributed traits allows us to estimate the role of heredity

  • People can differ in terms of genetics or non-genetics

  • To the extent that a phenotype is different among individuals, to what extent is this difference attributable to genetic variation or non-genetic variation among individuals?

  • If heredity is important for X (e.g., height), then 2 people who are related should be more similar in height than 2 people not related

    

Genetic variance explains___of individual variance at age 15 observed in rule-breaking behaviour (e.g., property crime) but only____ at age 10

Genetic variance explains 80% of individual variance at age 15 observed in rule-breaking behaviour (e.g., property crime) but only 20% at age 10

are genetic influences mediated by peers?

• Genetic influences are mediated by sensation-seeking, and exacerbated by deviant peers

  

adolescents brain and peer breakdowns

• Ventral striatum (incentive-processing system) responds increasingly to rewards in adolescence, especially when peers are involved

• Individual differences (e.g., hormones during puberty) in reward- responsive brain regions may mediate genetic risk for problem behaviours

• Higher testosterone (endogenous and exogenous) correlates with more reward seeking, greater VS activation

  

alcohol and tobacco use in the brain and peer influences

• Genetic factors (own or sibling’s use) correlated with increased exposure to best friends with heavy substance use

• Adolescents who were genetically liable to substance use were more vulnerable to adverse influence of best friends

• Not just if genetically suspectable but also more vulnerable to the influence of best friends who use

  

white and grey matter?

White matter = fatty tissue

• myelin

Grey = dendrites and cell bodies

 

• Grey matter volume in childhood

• Postmortem studies suggest changes in grey matter volume reflect synaptic proliferation followed by synaptic pruning

• Grey matter seems to peak 1-3 years earlier in female brains

• Increase in functional and structural connectivity, changing balance between limbic-frontal function, extends into adulthood

  

how does testostoronce affect white matter

Using a voxel-wise approach in neuroimaging (as opposed to whole brain or ROI) reveals increase in density between ages 4-17 years, although in male brains testosterone appears to decrease white matter

sex difference in white matter

• white matter density across age in cortico-spinal tract as a function of age

  • Increased with age in girls

  • Decreases with boys

    • Testosorone decreases it

• Androgens and estrogens may play differential roles during puberty in terms of white matter maturation

  

when is the intercrinaial myelin peak?

age 50

non human primate synaptic pruning

• Non-human primate brains demonstrate synaptic density that increases around 3 months, then declines by 10% by age 2 years, and 40% declining between 3-5 years (analogous to human adulthood)

  

human synaptic pruning

• In humans, synaptic density reaches its peak in childhood, followed by synaptic pruning in early (auditory cortex) to mid-adolescence (prefrontal cortex), but continues at a slower rate into adulthood

  

egray matter _____ in frontal lobes to improve what things?

• Gray matter thinning in frontal lobes correlates with improved cognitive performance, such as verbal and spatial memory

  

alcohol abuse on the brain memory and grey matter?

• Detrimental effects of alcohol are magnified during adolescence

  • Memory impairment worse for ages 21-24 than 25-29

  • In adult brain, chronic alcohol abuse associated with cortical gray matter thinning in PFC

 

Mechanisms for neural plasticity

long-term potentiation (synaptic efficiency), synaptogenesis, axonal sprouting, dendritic remodeling, neurogenesis, recruitment.

During adolescence, _____, _____, and ____ alter structure and function of neural networks

Tourette syndrome theory

• Theory that tics are the result of abnormal motor pathways in the networks connecting cortex to basal ganglia and thalamus

certain areas and cortical thinning with toureetes syndrome

Some regions are significantly thinner than control children (sensorimotor cortex and Broca’s areas), and more severe tic symptoms associated with more extensive cortical thinning

what happens in adolescents leadingg to more severe toureetes symptoms

In some individuals, plasticity is reduced during adolescence, leading to more severe symptoms, greater activation of neural systems that support inhibitory control to maintain task performance, and relative persistence of tics into adulthood.

unmedicated depressed adults brains

• in unmedicated depressed adults, cortex is thicker than healthy controls.

antidepressant treatment changes what in the brain ?

• Successful antidepressant treatment reduces cortical thickness to normal levels

 

developmental systems theory

experience drives neural changes and neural changes support development

Piagets theory

• constructivist approach

• Stage theory

  • Sensorimotor, preoperational, concreate operational, formal operation

    

what did Piagets emphasis on

• Emphasis on maturation: active processes triggered by children’s desire to learn and solve problems

• Thinking is organized into schemes: assimilation & accommodation

formal operations

• Ability to reason about complex problems

• Can hold in working memory multiple variables at once

  

abstract thinking: formal logic

•  if A = B, and B = C, then A = C

  • If C is the same as A, you dont need to compare a and b bc we can infer it is the same

  • Children think it depends on what A, B, and C represent

    

abstract thinking: complex thinking

considering simultaneously multiple connections and interpretations (e.g., metaphors: literal & abstract meanings; sarcasm

define Metacognition

ability to think about own thoughts

• Inherent assumption that your own assessment is accurate. Children can think they know a lot, even when they don’t

  

how do students with high metacognition perform academically

• Students who have high metacognition perform better academically

  • Who can accurately assume their own assessment

    

do grades promote metacognitive awareness

• Metacognition is you assessing your own performance

• Grades exogenous = something from the outside

what are the limitation of Piaget's theory

• More criticism for formal operations than other stages

• Individual differences

• Cultural influences

• Beyond adolescence

individual differences in Paiget theory

• Because the natural environment is similar for all individuals, Piaget expected the typical experiences to be sufficient to drive maturation through the four cognitive stages

• Success rate in completing Piagetian formal operations tasks is 40-60%, even among late adolescents and adults

• Individuals also do not always apply formal logic in all contexts

  • Easier in situations with which there is expertise; easier among individuals who enjoy math & science

    

cultural differences in Piaget theory

• Performance on Piagetian tasks likely depends on extent to which formal schooling is a normal cultural experience

• Even in cultures without formal schooling, adolescents are better able to solve complex tasks than children

  • Requires the ability to take multiple perspectives, consider multiple facts/ideas at once, and think beyond the concrete world

 

emerging adulthood: Postformal thought

ability to think about the complexities of everyday life

emerging adulthood: pragmatism:

adapt logical thinking to the practical constraints of real- life situations (e.g., use permutations than working through every possible outcome)