Developmental Psychology

Developmental Psychology

Prenatal Development

  • Course of Prenatal Development

    • Comprises three main phases:

      • Germinal Stage:

        • Begins right after conception.

        • Zygote grows through rapid cell division (1→2→4→8→16→... to 150).

        • Zygote implants itself into the uterine wall, forming an embryo.

      • Embryonic Stage:

        • Genetic plan dictates the formation of organs.

        • Cells begin to differentiate (e.g., determining genetic sex).

      • Fetal Stage:

        • Begins after the 8th week.

        • Appearance of basic reflexes (e.g., grasping, sucking).

        • By 16 weeks, the brain is fully formed.

        • By 27 weeks, the fetus can hear sounds.

        • Marked by significant growth.

  • Teratogens:

    • Toxins during prenatal development that can cause irreparable damage (e.g., fetal alcohol syndrome).

    • The embryo/fetus is fragile and shares blood with the mother; thus, maternal substances affect its development.

Newborn Abilities

  • Innate Reflexes:

    • Postural Reflex: Ability to sit with support.

    • Grasping Reflex: Clings to caregivers.

    • Rooting Reflex: Turns head towards stimuli on the cheek.

    • Stepping Reflex: Prepares for walking by marching when held upright.

    • Reflexes help newborns avoid danger (e.g., loud noises, bright lights).

  • Social Reflexes: Includes cooing, smiling, and crying to encourage interaction.

  • Sensory Abilities:

    • Taste:

      • Preference for sweetness and recoil from rotten smells, indicating genetically influenced taste preferences.

    • Sight:

      • Can see about 12 inches at birth, improves over time.

      • Early recognition of faces (e.g., recognizing the mother).

      • Color vision develops with age.

      • Depth perception fully develops by three months.

    • Auditory:

      • Preference for human voices and familiar sounds that they heard in the womb.

Neural Development

  • Newborns possess many neurons at birth that require environmental stimulation to form connections.

  • Synaptic Pruning:

    • Occurs around age 11; unused neural connections are destroyed to enhance efficiency.

    • This illustrates the interaction between nature and nurture in development.

  • Sensitive Periods:

    • Early years are critical for development; plasticity is highest in infancy.

    • Certain skills (e.g., language) require exposure during specific periods for optimal development.

Motor Development Milestones

  • Developmental milestones (ages in months):

    • 2-3: Lifts chin, chest up.

    • 4-5: Rolls over.

    • 6: Sits with support.

    • 7: Sits without support.

    • 9-11: Stands holding on, pulls self to stand.

    • 12: Stands alone; walks independently by 15 months.

Adolescence Development

  • Transition Characteristics:

    • Marked by physical growth, sexual maturity, and emotional changes during puberty.

    • Boys: Increase in testicle size; Girls: Development of breast tissue and menarche onset.

  • Adulthood Development:

    • Gradual physical decline starts around age 30, intensifying in later years (70s).

Gender Development

  • Sex vs. Gender:

    • Sex: Biologically influenced characteristics that classify individuals as male, female, or intersex.

    • Gender: Socially constructed roles, behaviors, and attributes a culture associates with an individual’s sex.

Language Development

  • Language Acquisition:

    • Explains the brain's capacity to learn any language.

    • Composed of:

      • Phonemes: Smallest sound units.

      • Morphemes: Smallest meaning units.

      • Grammar: Rules governing language structure.

Language Development Stages**:

  • Prelinguistic Stage (Birth-6 months): Cries and coos to express needs.

  • Babbling Stage (6-12 months): Combination of sounds (e.g., "bababa").

  • Holophrastic Stage (12-18 months): Use of single words to convey complete ideas.

  • Two-word Stage (18-24 months): Simple two-word sentences.

  • Telegraphic Speech Stage (24-36 months): Short sentences, omitting unnecessary words.

  • Complex Sentence Stage (36+ months): Use of complex sentences to express ideas.

Social Development**:

  • Caregiver-Infant Attachment:

    • Formed through emotional relationships laying foundations for future interactions.

  • Attachment Styles:

    • Secure Attachment: Comfortable with caregivers; distressed but quickly calms on reunion.

    • Insecure Attachment:

      • Anxious-Ambivalent: Upset at separation; difficulties settling after return.

      • Avoidant: Ignored caregivers on reunion, stressed when they leave.

Parenting Styles**:

  • Authoritarian: Strict with little warmth; emphasizes obedience.

  • Authoritative: Sets high expectations but is warm and supportive.

  • Permissive: Few rules; allows children to make their own decisions.

  • Uninvolved: Indifferent, often neglectful of children’s needs.

  • Parenting styles influence child’s confidence, sociability, and behavior patterns significantly.

Identity Development in Adolescence**:

  • Explored through Marcia's stages questioning exploration of beliefs and commitment.

  • Parental influence remains important but evolves as adolescents gain independence.

Summary Notes**:

  • Development is influenced by both nature (genetics) and nurture (environment and upbringing) across the lifespan from womb to tomb.