Chapter 9 Vocab

developmental psychology - The study of physical, cognitive, and social change throughout the lifespan (e.g., examining how children develop language skills).

zygote - A fertilized egg that undergoes rapid cell division before developing into an embryo (e.g., the first two weeks after conception).

embryo - The developing human organism from about 2 weeks after fertilization through the second month (e.g., when the heart begins to beat).

fetus - The developing human from 9 weeks after conception to birth (e.g., when a baby starts kicking in the womb).

teratogens - Harmful agents, such as chemicals or viruses, that can reach the embryo or fetus during prenatal development and cause harm (e.g., alcohol, drugs, or radiation exposure).

fetal alcohol syndrome (FAS) - A condition in a child resulting from alcohol exposure during pregnancy, leading to physical and cognitive abnormalities (e.g., small head size, learning disabilities).

habituation - Decreased responsiveness to a repeated stimulus (e.g., a baby losing interest in a toy after seeing it multiple times).

maturation - Biological growth processes that enable orderly changes in behavior, mostly uninfluenced by experience (e.g., learning to walk after muscle and neural development).

cognition - All mental activities associated with thinking, knowing, remembering, and communicating (e.g., problem-solving and decision-making).

schema - A mental framework that helps organize and interpret information (e.g., a child thinking all four-legged animals are dogs).

assimilation - Interpreting new experiences using existing schemas (e.g., a child calling a cat "dog" because it has four legs).

accommodation - Adapting schemas to incorporate new information (e.g., learning that cats and dogs are different animals).

sensorimotor stage - Piaget’s stage (birth to about 2 years) where infants know the world through sensory impressions and motor activities (e.g., grasping objects and putting them in the mouth).

object permanence - The understanding that objects continue to exist even when not seen (e.g., a baby searching for a hidden toy).

preoperational stage - Piaget’s stage (ages 2-7) where children represent things with words and images but lack logical reasoning (e.g., believing the moon follows them).

conservation - The principle that quantity remains the same despite changes in shape (e.g., a child thinking a taller glass has more water than a wider one).

egocentrism - In Piaget’s theory, the difficulty in seeing things from another’s perspective (e.g., a child covering their eyes and thinking no one can see them).

theory of mind - The ability to understand others' thoughts, beliefs, and feelings (e.g., realizing a friend is sad even if they don’t say it).

autism spectrum disorder (ASD) - A developmental disorder with challenges in social interaction, communication, and repetitive behaviors (e.g., difficulty understanding facial expressions).

concrete operational stage - Piaget’s stage (ages 7-11) where children gain logical thinking about concrete events (e.g., understanding that 3+4 = 7 and 7-4 = 3).

formal operational stage - Piaget’s stage (ages 12+) where people develop abstract reasoning (e.g., solving hypothetical problems).

stranger anxiety - The fear of unfamiliar people, common in infants around 8 months (e.g., crying when held by a new babysitter).

attachment - An emotional tie with another person, especially between an infant and caregiver (e.g., a baby seeking comfort from their mother when scared).

critical period - A crucial time in early life when exposure to stimuli leads to normal development (e.g., learning language before puberty).

imprinting - The process by which certain animals form strong attachments during a critical period early in life (e.g., ducklings following the first moving thing they see).

temperament - A person’s characteristic emotional reactivity and intensity (e.g., a baby being naturally easygoing or fussy).

basic trust - According to Erikson, a sense that the world is predictable and trustworthy, formed during infancy with proper care (e.g., feeling safe exploring a playground).

self-concept - An understanding of who one is, developing around age 12 (e.g., recognizing oneself in a mirror and stating personal traits).

gender - The socially influenced characteristics by which people define male and female (e.g., cultural expectations of masculinity and femininity).

aggression - Any physical or verbal behavior intended to harm (e.g., bullying at school).

gender role - Expected behaviors for males or females in a given society (e.g., the expectation that women should be caregivers).

role - A set of expectations about social behavior (e.g., a teacher being expected to educate and guide students).

gender identity - A person’s sense of being male, female, or another gender (e.g., identifying as nonbinary).

social learning theory - The theory that we learn gender-linked behaviors by observing and imitating others (e.g., a boy watching his father shave and wanting to try).

gender typing - The acquisition of traditional masculine or feminine roles (e.g., a girl preferring dolls and a boy preferring toy cars).

transgender - A term for people whose gender identity differs from their assigned sex at birth (e.g., someone assigned female at birth identifying as male).

adolescence - The transition from childhood to adulthood, marked by puberty (e.g., teenagers experiencing identity exploration).

identity - One’s sense of self, formed through social interactions (e.g., a teen exploring different hobbies and beliefs).

social identity - The "we" aspect of self-concept, based on group memberships (e.g., identifying as an athlete, musician, or gamer).

intimacy - The ability to form close, loving relationships, typically in young adulthood (e.g., deep friendships or romantic bonds).

emerging adulthood - A period from late teens to mid-20s when individuals explore their identity and independence (e.g., living independently for the first time).

X chromosome - The sex chromosome found in both males and females; females have two, males have one (e.g., inherited from both parents in females).

Y chromosome - The sex chromosome found only in males, determining male biological traits (e.g., inherited from the father).

testosterone - The primary male sex hormone that influences development and behavior (e.g., increasing muscle growth and deepening voice during puberty).

puberty - The period of sexual maturation, when a person becomes capable of reproduction (e.g., voice deepening in boys and breast development in girls).

primary sex characteristics - The body structures directly involved in reproduction (e.g., testes in males, ovaries in females).

secondary sex characteristics - Nonreproductive traits that develop during puberty (e.g., facial hair in boys, widened hips in girls).

menarche [meh-NAR-key] - A female’s first menstrual period (e.g., typically occurring around age 12-13).

AIDS (acquired immune deficiency syndrome) - A disease caused by HIV that weakens the immune system (e.g., increasing susceptibility to infections).

sexual orientation - A person’s enduring sexual attraction to individuals of the same, opposite, or both sexes (e.g., identifying as heterosexual, homosexual, or bisexual).

menopause - The natural end of menstruation, marking the end of reproductive ability (e.g., typically occurring around age 50).

cross-sectional study - A research method comparing people of different ages at the same time (e.g., measuring intelligence in 20-year-olds and 60-year-olds).

longitudinal study - A research method that studies the same individuals over a long period (e.g., tracking cognitive abilities from childhood to old age).

social clock - The culturally preferred timing of major life events (e.g., getting married in one’s late 20s).