Development

Psyc – week 7

Development Part 1

Developmental psychology

  • The study of continuity and change across the life span
    • Infancy (birth to btwn 18-24 months)
    • Childhood (from 18-24 months to 11-14yrs)
    • Adolescence (from 11-14 years to 18-21 years)
    • Adulthood (from 18-21 years to old age)

Prenatal development

  • There are 3 prenatal stages (from conception to birth)
  • Germinal 🡪 embryonic 🡪 fetal
  • Germinal:
    • Conception to 2 wks
      • Zygote: fertilized egg containing chromosomes from both a sperm and an egg
      • 50% of zygotes don’t make it as they become defective
  • Embryonic:
    • Wk 2-8
    • Cells begin to differentiate
    • 30 days – poppy-seed size
    • 8-9 wks – olive sized
      • Has arms, legs, beating heart
  • Fetal stage:
    • Wk 9 – birth
    • Fetus develops skeleton and muscles
    • Can move
    • Brain development (neural tube develops and the spinal cord)

Infant brain

  • Newborn’s brain is 25% of adult size
  • Why are humans born with such underdeveloped brains?
    • Can’t be full size because we cannot support this, especially just on 2 feet
    • Might be better to have a underdeveloped brain to have room for evolvement
      • Important to be able to adapt to physical surrounding and social environments

Prenatal environment

  • Placenta: organ in the womb that links bloodstream of mother to the fetus, permitting the exchange of biological materials
  • Foods and substances a mother ingests affect development
    • Teratogens: agents that pass from the mother and impair development (alcohol is most common)
    • Fetal alcohol syndrome: developmental disorder that stems from heavy alcohol use by the mother during pregnancy 🡪 causes brain developments
  • The womb is dark, but not silent
    • Heartbeat, GI, mother’s voice
      • Research
        • Mother’s vs. stranger’s voice (HR, suckling)
          • Fetus has a higher heartrate and more suckling when mother was talking
        • Native vs foreign language (suckling)
          • Suckle more with native language mother speaks
        • Cry in own language e.g. tonal vs non-tonal language and pitch fluctuations
          • Vocal reflections are thought to help babies bond with their mothers – imitate mothers behaviour to attract her

Infancy – perceptual development

  • Newborns:
    • Have poor distance vision
    • Can see things that are 8-12 inches away (why this distance? – distance that they can feed at)
    • Habituate to visual stimuli (respond less to repeated exposure of the same stimuli) (how do we know? – can see it in experiments)
    • Can mimic facial expressions within the first hour of life

Infancy – motor development

  • Motor reflexes: innate, specific patterns of motor response triggered by specific sensory stimulation
    • E.g. rooting – touch a babies cheek will make them turn their head towards it as it’s evolutionarily adaptable & suckling; grasping; stepping; moro – slowly ‘swinging’ a child and they will throw their arms back
  • Cephalocaudal rule: motor skills tend to emerge in sequence from the head to the feet
  • Proximodistal rule: motor skills tend to emerge in sequence from center to the periphery

Infancy – cognitive development

  • Piaget suggested 4 stages of cognitive development in which infants & children learn
  • 1) sensorimotor (0-2)
    • Acquire information about the world by sensing and moving around within it
    • Schemas: theories about the way the world works (e.g. nipple = food) – allow us to predict future events
    • Assimilation: applying an experience to pre-existing schemas (e.g. bottle nipple = food)
    • Accommodation: revising a schema following new information (e.g. dad boob = mouthful of haor, no food)
    • Object permanence: schema that objects continue to exist even when they are not visible (ex. A parent hiding an object and a child thinks it disappears – peek-a-boo)
  • 2) preoperational (2-6)
    • Children develop a preliminary understanding of the physical world
    • Think the way the world appears is the way it is
    • Start to develop theory of mind
    • Ex. Water in water bottle will equal the amount poured in a smaller glass but they think the bottle contains more
  • 3) concrete operational (6-11)
    • Children learn how various operaions (actions) can affect or transform concrete objects
      • Conservation: notion that the quantitative properties of an object don’t vary despite changes in the object’s appearance
      • Learn the world may appear one way but it is in fact another way
      • Ex. Can explain why the water bottle is the same amount of water
  • 4) formal operational (11+)
    • Children can solve nonphysical problems; reasoning skills; abstract thinking
    • E.g. define the world “hypothetical”

How do we measure what young infants know?

  • Sucking
    • E.g. preferences (music)
    • E.g. classical and operant conditioning (i.e. learning)
  • Eye movement
    • Preferential gaze direction
    • E.g. learning and speech recognition
  • Preferential looking time
    • E.g. habituation (change the action during habituation and see if they react)
    • E.g. impossible events (more likely to look at these kind of events)

Discovering other minds

  • Egocentrism: failure to understand that the world appears different to different observers; observed during preoperational stage
    • Preoperational children expect others to see the world the way they do
    • Perception and beliefs:
      • 3 yrs old fail to realize other people don’t see or know what they know
      • False-belief task
  • Desires and emotions
    • Children seem to understand other’s desires (e.g. likes/dislikes)
    • Children have difficulty understanding different emotional reactions in others, until ~6yrs old
    • Theory of mind: ability to attribute mental states to oneself and to others, and to understand that other have beliefs, desires, intentions, and perspectives that are different from one’s own
      • Language is important for the development of ToM
        • E.g. children with autism & deaf children whose parents do not use ASL have difficulty with ToM
      • Influenced by # of siblings, frequency of pretend play, SES, culture, talking about thoughts and emotions in the home

Criticisms and limitations to theories

  • Revisions to Piaget’s theory:
    • Newer theories see the stages as continuous, not discrete
    • May oscillate between stages
    • Children may acquire abilities earlier than proposed
  • Other considerations:
    • Children may give correct answers to modified version of false-belief task

Development Part 2

Cultural influences

  • Vygotsky believed children develop through interactions with members of their own culture
  • Ability to learn from others depends on 3 fundamental skills:
    • 1) joint attention: ability to docus on what another person is focused on; prereq for social learning (e.g. 3 months = head turn, 9 months = look with eyes)
    • 2) imitation of intention: ability to do what another person does
    • 3) social referencing: ability to use another person’s reactions as information about how to think about the world (e.g. danger)

Caring and belonging

  • Caregivers are essential for the survival of human infants
  • What do they provide?
  • Orphan studies (WWII)
    • Had safety, warmth, food
    • Physical, cognitive and emotional impairments
    • 40% death rate
    • What was missing?

Social development

  • Harlow conducted attachment experiments with baby rhesus monkeys
  • Discovered that when monkeys were deprived of social contact in the first 6mos, they:
    • Developed behavioral abnormalities
    • Were incapable of communicating with or learning from others
    • Were incapable of normal sexual behaviour
    • Became rejecting mothers

Attachment

  • Lorenz discovered the concepts of imprinting in newly hatched goslings
  • Bowlby argued that infants innately channel their signals to primary caregivers to form attachment
    • What can infants do?
    • Data collection by infant 6 months = result – primary caregiver determined
  • Attachment: emotional bond that forms with primary caregiver just after birth; social reflex (predisposition)
  • Without the bond, infant is at serious risk of physical, mental and emotional impairments
  • Strange situation: behavioural test developed by Ainsworth used to determine a child’s quality of attachment
    • Infants react in 1 of 4 ways:
      • Secure, avoidant, ambivalent, disorganized
  • Attachment style: characteristic patterns of reacting to presence and absence of one’s primary caregiver

Attachment styles

  • Secure: infant not distressed when caregiver leaves, and acknowledges return; or is distressed when caregiver leaves but is consolable; 60% of American infants
  • Avoidant: infant not distressed when caregiver leaves; does not acknowledge return; 20%
  • Ambivalent: infant distressed when cg leaves; difficult to calm when she returns; 15%
  • Disorganized: no consistent response patterns; 5%
    • Many cases involve child abuse

Origin of attachment styles

  • Temperaments: biologically based patterns of emotional reactivity
    • +ve mood, fearfulness, activity, irritability etc.
    • Physiological and self-report by parent
    • Present at birth, stable over time
  • Primary cg’s responsiveness and sensitivity – big role
  • Internal working model of relationships: a set of beliefs about the self, the primary cg, and the relationship between them (e.g. can or cannot rely on needs being met)

Effects of attachment styles

  • Securely attached children overall do better than insecurely attached
  • They have better:
    • Cognitive functioning
    • Emotional adjustment
    • Psychological well-being
    • Social relationships
    • Academic achievements
    • Success in adulthood

Development Part 3

Adolescence

  • From onset of sexual maturity (11-14 yrs)
  • To beginning of adulthood (18-21yrs)
  • Puberty: bodily changes associated with sexual maturity
    • Primary sex characteristics: directly involved in reproduction
    • Secondary sex characteristics: strictures that change dramatically with sexual maturity, but are not directly involved in reproduction
    • Neurological changes
      • Inc in growth of brain tissue that connects different brain parts
        • E.g. btwn temporal and parietal lobes
        • Proliferation, then pruning in the prefrontal cortex

The Protraction of Adolescence

  • Considerable variation exists in the onset of puberty (between genders, cultures, time periods/eras)
  • Puberty age of onset has greatly fallen over last few decades
    • Improved diet (fat) and health
    • Chemicals (e.g. mimic estrogen)
    • Stress
  • Longer and more varied transition period than historically
    • The age of puberty decreased but the age of adulthood inc

The moody teen

  • Is it a myth?
  • No such thing as “raging hormones”?

Adolescent behaviour

  • Adolescents “no moodier than children”
    • Hormones = small mood fluctuations
  • Emotional regulation
  • More impulsive
  • More susceptible to peer influence
  • Some experimentation
    • Rarely long term negative patterns of behaviour
  • Some riskier behaviours
  • But overall, adolescents do make good decisions (when?)

How do peers affect decision making?

  • Correlation between number of crashes being higher when with friends vs being alone

Sexuality

  • Effects of early maturation (puberty) is more negative for girls
  • Timing of puberty has large influence on emotional and behavioural problems in girls (inconsistent effect in boys)
  • Negative consequences: distress, depression, delinquency, disease
  • Early maturing girls don’t have as much time to adjust
  • Look older, treated like adults
  • Pressure to look good (pretty = sexy)
  • Attention from older boys and men
    • Adverse ST and LT effects

Sexual orientation

  • Largely biological (and some possible smaller environmental) influences
  • Child consistent gender noncomforming behaviour predicts sexual orientation
  • Understanding and expressing one’s sexuality and sexual identity is particularly stressful during this period – especially if one does not identify as heterosexual or cis-gender
  • 1/25 Canadians aged >15 identified as homosexual, bisexual, or transgender. Highest 15-24 range
  • High rates of MH issues due to adjustment
    • Better in more accepting countries and immediate environments

Heterosexual🡨-----------Bisexual-------------🡪Homosexual

Sexual Behaviour

  • Adolescent interest in sex often precedes knowledge about it
    • Rate at which young Canadians engage in sex is higher or lower?
    • There is a increase or decrease in condom use rates
    • Sex education may be important to deter pregnancy/disease

Adolescent social development

  • Shift in emphasis from family to peer relations
    • Teens choose their peers; play active role in own development
    • Peer relationships evolve and “peel off”; couples form
    • Peer pressure forms but has less influence as we age
  • Adolescents struggle for autonomy
    • Conflict with parents, reduced closeness, reduced time spent

Development Part 4 (start of week 8)

Adulthood

  • Stage of development beginning 18-21 and ending at death
  • Development slows down
  • Changes that take place are:
    • Physical
    • Cognitive

Changing abilities

  • Abilities and health peak in 20s and deteriorate after 26-30
  • Physical changes lead to psychological consequences (cognitive decline)
    • Prefrontal cortex and associated brain structures deteriorate most quickly
    • Decline on tasks involving initiation, strategy, effort
    • Overall memory decline
  • Overall cognitive performance remains high due to:
    • Compensation of aging brain by calling on other neural structures
    • Use brain more skillfully – much due to long-term practice (e.g. efficiency)
    • Knowledge accumulation
    • Brain becomes de-differentiated, bilateral asymmetry disappears
    • Age of peak abilities is at a younger age

Changing emotions and goals

  • Socioemotional selectivity theory (EA code): younger adults are oriented towards future-pertinent (useful) information, older adults focus on (positive) emotional satisfaction in the present, perhaps because of shortened futures
    • Older adults focus on & remember more positive experiences and emotions
    • Better able to sustain positive emotions & inhibit negative ones
    • More emotionally stable, better at emotional regulation
    • Feel more attractive over 65 than under 34

Changing goals

  • More willing to forego personal gains and interested to contribute to the public good
  • More generous
  • Fewer friends
    • Less time spent with mere acquaintances
  • More close-knit family/friends-oriented
  • People report late adulthood to be one of the happiest and most satisfying times of their life

Changing roles

  • Current university-aged Canadians will later…
    • Get married around = 30
    • Have 1.7 children
    • Greatest source of joy = partner and their children
    • Half of 18+ yos are married/common law
    • People in committed relationships are happier and have better health (correlation does not equal causation)
    • Marital satisfaction ebbs and flows e.g. with more children
    • Women tend to be less happy when raising children
      • Multi-role demands?
      • Also less reported satisfaction with partner with more kids

Development chapter summary

Without looking back at notes, in one sentence, tell you neighbour one interesting/surprising thing you learned:

  • Prenatality
  • Infancy
  • Adolescence
  • Adulthood/older adulthood