unit 3 developmental psychology

introduction to developmental psychology pdf

• studies how people grow, change and develop throughout their lives

• looks at physical, cognitive, social, and emotional changes

chronological development

• specific order and timing of changes that occur as people age

  • milestones happen at certain ages

  • puberty, cognitive decline

thematic development

• looks at big patterns over lifespan

  • stability and change, nature and nurture, etc,

methods of studying human development

cross sectional

• observe or test different groups of people of varying ages at a single point in time

How?

• select participants from different age groups (eg. children, adolescents, adults, older adults)

• measure specific variables of interest

• compare results

eg. compare memory performance of 10, 20, 30, 40 to understand how memory changes with age

advantages

• quick, cost-effect

  • data = collected at one time point

  • faster, less expensive

• snapshot of differences

  • help identify patterns and trends across the lifespan

disadvantages

• cohort effects

  • differences might be due to generational/ cultural factors, not because of age

• no individual development

  • do not track individual changes over time

longitudinal studies

• observe/ test same group of people over an extended period

how it works

• select a group of participants and repeatedly measure the same variables at multiple times points throughout their lives

• allows fir the examination of changes within individuals over time

eg. follow a group of children from age 3 to age 25, assessing their cognitive development

advantages

• tracking development over time

  • detailed information about how individuals change overtime

  • identify patterns of development

• less cohort effects

  • same individuals are studied over time

  • differences are more likely due to age-related changes

disadvantages

• time-consuming and expensive

  • require long-term commitment of resources and time

  • more expensive and logistically challenging

• attrition

  • participants might drop out the study over time

  • smaller sample size and potentially biased results

• historical effects

  • events occurring during the study can influence findings

3 major themes of developmental psychology

nature vs nurture

• whether genetics (nature) or environment (nurture) has a bigger impact on who we become

nature

• our genes and biological makeup play the most important role in shaping our traits and behaviours

• studies of twins

  • similarities in intelligence, personality, behaviors, even when they are raised in different environments

• emphasises that many of our development are determined by DNA and biological processes

nurture

• believe that surroundings and experiences are more important

  • upbringing, culture, social interactions

  • education, socioeconomic status, life experiences

• both nature and nurture work together to shape our development

stability and changes

• whether our traits and behaviours remain consistent throughout life or change over time

stability

• many aspects of our personality, intelligence, other traits are established early in life and remain constant

• genetic factors play a crucial role in setting these traits

  • persist as we age

• regardless of life experiences

• personality

eg. child who is naturally shy may remain shy throughout adulthood regardless of life experiences

change

• undergo significant transformations over their lifetime due to various influences

  • life experiences, environment, personal choices

• traits are not fixed and can evolve with new experiences and circumstances

• cognitive abilities, social skills, physical capabilities

e.g. someone who is introverted during childhood may become more outgoing due to positive social experiences and personal growth

continuity vs stages

• centers on how people change and grow over time

continuity

• development is a gradual, continuous process

• changes occur slowly and steadily throughout a person’s life

• development = smooth progression without clear-cut stages

stages

• development occurs in distinct phases, each marked by specific, qualitative changes

• theories like Piaget’s stages of development, Erikson’s psychosocial stages

• people progress through set stages in a specific order

• highlights these shifts as clear evidence of different ways of understanding and interacting with the world at various life stages

physical development

prenatal development

physical development

• starts with the germinal stage

  • from conception to two weeks

  • where zygote attaches to the uterine wall

• in embryonic stage,

  • from 3-8 week

  • major organs form

  • heart begins beating by the fourth week

  • arms and legs start developing

• during fetal stage

  • 9 week until birth

  • embryo begins to look distinctively human as organs and systems grow and mature

teratogens

• substances that may lead to birth defects in am embryo or fetus

  • alcohol, drugs, environmental toxins, certain medications

• impact depends on several factors

  • length of exposure

  • stage of pregnancy that exposure occurs

  • genetic factors

  • type of teratogen

• maternal illness, genetic mutations, hormonal, environmental factors also influence

maternal illness: rubella (German measles), sexually transmitted infections

• cross the placenta and harm developing fetus

Genetic mutations: inherited or spontaneous

• cause physical and cognitive abnormalities

  • down syndrome: extra copy of chromosome 21

  • sickle sell anemia: caused by a mutation in the hemoglobin gene

hormonal imbalances: in mother

• affect fetal development

  • excess androgens: lead to masculinization of female fetuses

  • insufficient thyroid hormone: impair brain development

environmental factors: poor nutrition, lack of prenatal care, exposure to toxins

• negatively impact fetal growth and development

most well known teratogens

• alcohol

• can lead to fetal alcohol syndrome (FAS)

  • characterised by a range of physical, cognitive, and behavioural problems

  • growth deficiencies, facial abnormalities, intellectual disabilities

• severity depends on timing, duration, level of exposure

newborn development

reflexes

• automatic responses that indicate healthy physical and psychological development

rooting reflex

• baby turns its head toward a touch on the cheek and opens its mouth

• helps with breastfeeding

startle reflex/ Moro reflex

• causes a baby to throw its arms out and then pull them back in when startles

• demonstrates basic protective response

grasping reflex

• baby closing its fingers around an object placed in its hand

• shows early motor development

these reflexes indicate that a newborn’s nervous system is functioning correctly and that they are on track for developmental milestones

social connection

• newborns have natural preference for sights and sounds that promote social responsiveness

  • crucial for early bonding and communication

• newborns spends more time looking at face-like images

  • innate attraction to human faces

• infants gaze longer at objects 8-12 inches away

  • typical distance between a nursing infant’s eyes and their mother’s face

• ensures that newborns engage in eye contact

• at birth, you have the highest number of brain cells you will ever process

  • but nervous system is still immature

• as you grow, neural networks become increasingly complex

infant development

maturation

• natural growth and development process, guided by genetic and biological factors

  • enables individual to reach full potential

• in infants, maturation is evident in the rapid development of the brain

  • neural networks become increasingly complex

  • allows enhanced cognitive functions and physical abilities

• rapid brain development is crucial for motor skills, language acquisition, social interactions

  • importance of a nurturing environment

infantile amnesia

• inability to recall memories from the earliest years of life

• occurs because the brain structures responsible for long-term memory (hippocampus) are not yet fully developed in infancy

motor development

• encompasses the progression of physical skills that enable movement and corrdination

• divided into two categories

  • fine motor skills

  • gross motor skills

fine motor skills

• small muscles

• hands and fingers

• essential for tasks like grasping objects, holding a spoon, eventually writing

gross motor skills

• larger muscles in the arms, legs, torso

• crawling, sitting, standing, walking

4-6 months: rolling over

6-8 months: sitting

8-10 months: crawling

9-12 months: standing

12-15 months: walking

childhood development

maturation

• involves both nature and nurture interacting to shape development

• from age 3-6

  • rapid brain growth occurs in the frontal lobes

  • enhancing rational planning and the ability to control attention and behaviour

• intense period of brain development results in significant cognitive and emotional progress

nature provides genetic blueprint

nurture supports these developments

• studies with rats have shown that those raised in enriched environments developed significantly more cerebral cortex compared to those in impoverished environment    

  • impact of a stimulating environment on brain development

critical period/ sensitive period

• crucial window of time when the brain is particularly receptive to certain types of learning and development

  • when the brain is highly sensitive to certain experiences

• exposure to stimuli such as spoken, written, or signed language is essential

  • without it, a person will never fully master language skills

• lack of visual experience can result in permanant deficits in normal perception

  • neural circuits responsible for these functions need specific experiences to develop properly

imprinting

• rapid, instinctive learning process that occurs during a critical period in some animal species

  • birds form a strong attachment to the first moving object they encounter (usually parent)

    • allows them to quickly learn to follow and identify their caregivers, ensuring their survival

• Konrad Lorenz: imprinting in geese

  • showing that goslings would follow him if he was the first object they saw after hatching

• if these critical periods pass without necessary stimuli

  • brain’s ability to adapt and learn in those areas in significantly diminished

adverse childhood experiences (ACEs)

• traumatic events in a child’s life

  • abuse, neglect, household dysfunction

• can have profound and lasting effects on physical, emotional, cognitive development

• exposed to ACEs have higher risks for mental health issues, etc.

• disrupt brain development, lead to problems with learning, behavior, etc.

adolescent development

• childhood to adulthood

• 12-18 age

• significant physical, emotional , psychological changes

  • undergo puberty

  • stronger sense of identity

  • seek greater independence

puberty

• children transition to adulthood

• triggered by hormonal changes

•     begins with the activation of the hypothalamic-pituitary-gonadal (HPG) axis

• experience significant physical and hormonal changes

• growth spurt

  • rapid increases in height and weight

  • changes in body composition and proportion

• development of primary sex characteristics

  • maturation of the reproductive organs

• secondary sex characteristics

  • growth of body hair

  • breast development in girls

  • deeper voice in boys

• production of sex hormones

  • testosterone in males

  • estrogen in females

menarche (primary)

• onset of menstruation

• key milestone in female puberty

• timing of puberty can vary widely

  • 8-14 for girls

  • 9-15 for boys

• influenced by genetics, nutrition, environmental factors

• can affect adolescents’ physical and emotional development

  • may mature different rates compared to peers

the teenage brain

• significant changes that impact behavior and decision-making

• synaptic pruning

  • unused neural connections are eliminated

  • increase brain efficiency

• prefrontal cortex, responsible for rational planning and impulse control, is still development

  • adolescents’ judgment often lags behind their emotional and hormonal development

• teenagers may experience heightened impulsivity, emotional storms, engage in risky behaviours

• underdeveloped prefrontal cortex + intense emotions= critical period for learning and growth

adulthood development

emerging adulthood: 18- mid 20s

• exploration and self-discovery

early adulthood: 20s-30s

• building careers and forming intimate relationships

middle adulthood: up to age 65

• stability and personal growth

late adulthood: years after 65

• reflection, retirement, maintaining health

middle adulthood

• gradual physical decline

  • reduced muscle mass

  • decreased bone density

  • slower metabolism

  • deteriorated vision and hearing

Reproductive ability peaks in early adulthood and declines with age

• menopause: late 40s or early 50s

  • end of menstrual cycles

  • significant drop in estrogen levels

• gradual decrease in testosterone in men

  • affecting energy and mood

  • declined vision and hearing

• what individuals experience depends on their personal health and habits

  • diets, exercise, stress management

  • can influence impact of these changes

late adulthood

• various physical and cogntiive changes

• decline in sensory abilities

  • diminished vision, hearing, taste, smell

• decreased stamina, strength

  • daily activities more challenging

• brain undergoes changes

  • reduction in volume of certain areas

  • slower neural processing

  • decrease in cognitive functions

    • memory, problem-solving

Piaget’s cognitive development theory

Jean Piaget

• influential developmental psychologist concerned with the cognitive development of children

• studied children and identified 4 main cognitive stages

schemas

• categories of knowledge that help us interpret and understand the world

• used to modify/ add to/ change previously existing schemas

• ex. a child may have schema about a type of animal

  • id their only experience is with small dogs → might believe that all dogs are small

  • if they encounters a big dog → take in new information and modify the previous schema

assimilation

fitting new information into an existing schema

• taking in new information into our already existing schemas

• no change to the person’s current interpretation of reality

accommodation

• changing existing schemas when we gain new information

• new schemas may develop as a result of the changes

• perception of reality is changed

ex. when the child encounters a horse

adjusting or creating a new schema when the old one doesn’t work

• they might assimilate this information and call the animal a dog at first

• accommodation allows the child to adapt the existing schema to incorporate the knowledge that some four-legged animals are horses

4 stages of cognitive development

• sensorimotor stage: birth to 2 years

• preoperational stage: ages 2-7

• concrete operational stage: ages 7-11

• formal operational stage: ages 12 and up

sensorimotor stage (birth to 2 years)

• use senses and motor skills to learn about the world

• look and listen to things, touch and move objects

milstone: object permanence

• learning that things continue to exist even when they cannot be seen

preoperational stage (2-7)

• learn through pretend play

• struggle with logic and taking the point of view of other people

• become proficient in using mentals symbols

• struggling with understanding the idea of constancy

Lack of conservation

understanding that quantity stays the same despite changes in shape

• understanding that changing the form of a substance or object does not change its amount, overall volume, or mass

• ex. child believes that the taller, narrower glass contains more liquid

lack theory of mind

• ability to infer the mental states of other people

• = egocentrism

  • difficulty seeing from another’s perspective

animism

• believe that inanimate objects have feelings and thoughts just like living creatures

concrete operational stage (7-11)

• much stronger at using logic

• egocentrism begins to disappear

  • better at thinking about how other people might view a situation

• tend to struggle with abstract and hypothetical concepts

reversibility

• actions that can be reversed

• ex. water can be frozen then thawed to become liquie

• 2+3=5, 5-3=2

formal operational stage (12+)

• increase in logic, ability to use deductive reasoning, understanding of abstract ideas

• become capable of seeing multiple potential solutions to problems

• think more scientifically about thw world around them

• not all people achieve formal operational thinking

Vygotsky’s theory of the social child

• emphasized how the child’s mind grows through interaction with the socio-cultural environment

• children gain knowledge and skills primarily through interactions with others within their cultural and social environment

• emphasized learning is not an isolated process

  • but is deeply embedded in the context of social relationships and cultural tools

the zone of proximal development

• range of tasks that a child can perform with help but not yet independently

Scaffolding:

• is the temporary support provided to move someone through their ZPD

cognitive development in adults

• experiences changes in cognitive capabilities as they progress throguh lifespan’’

crystalizated intelligence

• accumulated knowledge and vocabulary

• remains relatively stable through adulthodo

fluid intelligence

• reasoning speed and abstract problem-solving

• peaks in early adulthood, declines with age