Vocabulary

Adoption study: A behavior genetic research method that involves comparison of adopted children to their adoptive and biological parents.
Agender: An individual who may have no gender or may describe themselves as having a neutral gender.
Ambivalent sexism: A concept of gender attitudes that encompasses both positive and negative qualities.
Anecdotal evidence: A piece of biased evidence, usually drawn from personal experience, used to support a conclusion that may or may not be correct.
Assent: When minor participants are asked to indicate their willingness to participate in a study. This is usually obtained from participants who are at least 7 years old, in addition to parent or guardian consent.
Attachment behavioral system: A motivational system selected over the course of evolution to maintain proximity between a young child and his or her primary attachment figure.
Attachment behaviors: Behaviors and signals that attract the attention of a primary attachment figure and function to prevent separation from that individual or to reestablish proximity to that individual (e.g., crying, clinging).
Attachment figure: Someone who functions as the primary safe haven and secure base for an individual. In childhood, an individual’s attachment figure is often a parent. In adulthood, an individual’s attachment figure is often a romantic partner.
Attachment patterns: (also called “attachment styles” or “attachment orientations”) Individual differences in how securely (vs. insecurely) people think, feel, and behave in attachment relationships.
Attrition: When a participant drops out, or fails to complete, all parts of a study.
Authoritative: A parenting style characterized by high (but reasonable) expectations for children’s behavior, good communication, warmth and nurturance, and the use of reasoning (rather than coercion) as preferred responses to children’s misbehavior.
Automatic empathy: A social perceiver unwittingly taking on the internal state of another person, usually because of mimicking the person’s expressive behavior and thereby feeling the expressed emotion.
Behavioral genetics: The empirical science of how genes and environments combine to generate behavior.
Benevolent sexism: The “positive” element of ambivalent sexism, which recognizes that women are perceived as needing to be protected, supported, and adored by men.
Bidirectional relations: When one variable is likely both cause and consequence of another variable.
Bigender: An individual who identifies as two genders.
Binary: The idea that gender has two separate and distinct categories (male and female) and that a person must be either one or the other.
Causality: In research, the determination that one variable causes—is responsible for—an effect.
Chutes and Ladders: A numerical board game that seems to be useful for building numerical knowledge.
Cisgender: A term used to describe individuals whose gender matches their biological sex.
Cohort effects: When research findings differ for participants of the same age tested at different points in historical time.
Concrete operations stage: Piagetian stage between ages 7 and 12 when children can think logically about concrete situations but not engage in systematic scientific reasoning.
Conscience: The cognitive, emotional, and social influences that cause young children to create and act consistently with internal standards of conduct.
Conservation problems: Problems pioneered by Piaget in which physical transformation of an object or set of objects changes a perceptually salient dimension but not the quantity that is being asked about.
Contingency management: A reward or punishment that systematically follows a behavior. Parents can use contingencies to modify their children’s behavior.
Continuous development: Ways in which development occurs in a gradual incremental manner, rather than through sudden jumps.
Correlation: In statistics, the measure of relatedness of two or more variables.
Cross-sectional research: A research design used to examine behavior in participants of different ages who are tested at the same point in time.
Data (also called observations): In research, information systematically collected for analysis and interpretation.
Deductive reasoning: A form of reasoning in which a given premise determines the interpretation of specific observations (e.g., All birds have feathers; since a duck is a bird, it has feathers).
Depth perception: The ability to actively perceive the distance from oneself of objects in the environment.
Developmental intergroup theory: A theory that postulates that adults’ focus on gender leads children to pay attention to gender as a key source of information about themselves and others, to seek out possible gender differences, and to form rigid stereotypes based on gender.
Discontinuous development: Discontinuous development
Dishabituation: When participants demonstrated increased attention (through looking or listening behavior) to a new stimulus after having been habituated to a different stimulus.
Distribution: In statistics, the relative frequency that a particular value occurs for each possible value of a given variable.
DNA methylation: Covalent modifications of mammalian DNA occurring via the methylation of cytosine, typically in the context of the CpG dinucleotide.
DNA methyltransferases (DNMTs): Enzymes that establish and maintain DNA methylation using methyl-group donor compounds or cofactors. The main mammalian DNMTs are DNMT1, which maintains methylation state across DNA replication, and DNMT3a and DNMT3b, which perform de novo methylation.
Drug diversion: When a drug that is prescribed to treat a medical condition is given to another individual who seeks to use the drug illicitly.
Effortful control: A temperament quality that enables children to be more successful in motivated self-regulation.
Elicited imitation: A behavioral method used to examine recall memory in infants and young children.
Empirical: Concerned with observation and/or the ability to verify a claim.
Endophenotypes: A characteristic that reflects a genetic liability for disease and a more basic component of a complex clinical presentation. Endophenotypes are less developmentally malleable than overt behavior.
Epigenetics: The study of heritable changes in gene expression or cellular phenotype caused by mechanisms other than changes in the underlying DNA sequence. Epigenetic marks include covalent DNA modifications and posttranslational histone modifications.
Epigenome: The genome-wide distribution of epigenetic marks.
Event-related potentials (ERP): The recording of participant brain activity using a stretchy cap with small electrodes or sensors as participants engage in a particular task (commonly viewing photographs or listening to auditory stimuli).
Event-related potentials (ERP): Measures the firing of groups of neurons in the cortex. As a person views or listens to specific types of information, neuronal activity creates small electrical currents that can be recorded from non-invasive sensors placed on the scalp. ERP provides excellent information about the timing of processing, clarifying brain activity at the millisecond pace at which it unfolds.
Fact: Objective information about the world.
False-belief test: An experimental procedure that assesses whether a perceiver recognizes that another person has a false belief—a belief that contradicts reality.
Falsify: In science, the ability of a claim to be tested and—possibly—refuted; a defining feature of science.
Family Stress Model: A description of the negative effects of family financial difficulty on child adjustment through the effects of economic stress on parents’ depressed mood, increased marital problems, and poor parenting.
Folk explanations of behavior: People’s natural explanations for why somebody did something, felt something, etc. (differing substantially for unintentional and intentional behaviors).
Formal operations stage: Piagetian stage starting at age 12 years and continuing for the rest of life, in which adolescents may gain the reasoning powers of educated adults.
Functional magnetic resonance imaging (fMRI): Entails the use of powerful magnets to measure the levels of oxygen within the brain that vary with changes in neural activity. That is, as the neurons in specific brain regions “work harder” when performing a specific task, they require more oxygen. By having people listen to or view social percepts in an MRI scanner, fMRI specifies the brain regions that evidence a relative increase in blood flow. In this way, fMRI provides excellent spatial information, pinpointing with millimeter accuracy, the brain regions most critical for different social processes.
Gender: The cultural, social, and psychological meanings that are associated with masculinity and femininity.
Gender constancy: The awareness that gender is constant and does not change simply by changing external attributes; develops between 3 and 6 years of age.
Gender discrimination: Differential treatment on the basis of gender.
Gender identity: A person’s psychological sense of being male or female.
Gender roles: The behaviors, attitudes, and personality traits that are designated as either masculine or feminine in a given culture.
Gender schema theory: This theory of how children form their own gender roles argues that children actively organize others’ behavior, activities, and attributes into gender categories or schemas.
Gender schemas: Organized beliefs and expectations about maleness and femaleness that guide children’s thinking about gender.
Gender stereotypes: The beliefs and expectations people hold about the typical characteristics, preferences, and behaviors of men and women.
Genderfluid: An individual who may identify as male, female, both, or neither at different times and in different circumstances.
Genderqueer or gender nonbinary: An umbrella term used to describe a wide range of individuals who do not identify with and/or conform to the gender binary.
Gene: A specific deoxyribonucleic acid (DNA) sequence that codes for a specific polypeptide or protein or an observable inherited trait.
Generalize: In research, the degree to which one can extend conclusions drawn from the findings of a study to other groups or situations not included in the study.
Genome-wide association study (GWAS): A study that maps DNA polymorphisms in affected individuals and controls matched for age, sex, and ethnic background with the aim of identifying causal genetic variants.
Genotype: The DNA content of a cell’s nucleus, whether a trait is externally observable or not.
Goodness of fit: The match or synchrony between a child’s temperament and characteristics of parental care that contributes to positive or negative personality development. A good “fit” means that parents have accommodated to the child’s temperamental attributes, and this contributes to positive personality growth and better adjustment.
Habituation: When participants demonstrated decreased attention (through looking or listening behavior) to repeatedly-presented stimuli.
Heritability coefficient: An easily misinterpreted statistical construct that purports to measure the role of genetics in the explanation of differences among individuals.
Histone acetyltransferases (HATs) and histone deacetylases (HDACs): HATs are enzymes that transfer acetyl groups to specific positions on histone tails, promoting an “open” chromatin state and transcriptional activation. HDACs remove these acetyl groups, resulting in a “closed” chromatin state and transcriptional repression.
Histone modifications: Posttranslational modifications of the N-terminal “tails” of histone proteins that serve as a major mode of epigenetic regulation. These modifications include acetylation, phosphorylation, methylation, sumoylation, ubiquitination, and ADP-ribosylation.
Hostile sexism: The negative element of ambivalent sexism, which includes the attitudes that women are inferior and incompetent relative to men.
Hypothesis: A tentative explanation that is subject to testing.
Identical twins: Two individual organisms that originated from the same zygote and therefore are genetically identical or very similar. The epigenetic profiling of identical twins discordant for disease is a unique experimental design as it eliminates the DNA sequence-, age-, and sex-differences from consideration.
Induction: To draw general conclusions from specific observations.
Inductive reasoning: A form of reasoning in which a general conclusion is inferred from a set of observations (e.g., noting that “the driver in that car was texting; he just cut me off then ran a red light!” (a specific observation), which leads to the general conclusion that texting while driving is dangerous).
Information processing theories: Theories that focus on describing the cognitive processes that underlie thinking at any one age and cognitive growth over time.
Informed consent: The process of getting permission from adults for themselves and their children to take part in research.
Institutional Review Boards (IRBs): A committee that reviews and approves research procedures involving human participants and animal subjects to ensure that the research is conducted in accordance with federal, institutional, and ethical guidelines.
Intention: An agent’s mental state of committing to perform an action that the agent believes will bring about a desired outcome.
Intentionality: The quality of an agent’s performing a behavior intentionally—that is, with skill and awareness and executing an intention (which is in turn based on a desire and relevant beliefs).
Interview techniques: A research method in which participants are asked to report on their experiences using language, commonly by engaging in conversation with a researcher (participants may also be asked to record their responses in writing).
Involuntary or obligatory responses: Behaviors in which individuals engage that do not require much conscious thought or effort.
Joint attention: Two people attending to the same object and being aware that they both are attending to it.
Levels of analysis: In science, there are complementary understandings and explanations of phenomena.
Longitudinal research: A research design used to examine behavior in the same participants over short (months) or long (decades) periods of time.
Malingering: Fabrication or exaggeration of medical symptoms to achieve secondary gain (e.g., receive medication, avoid school).
Mimicry: Copying others’ behavior, usually without awareness.
Mirror neurons: Neurons identified in monkey brains that fire both when the monkey performs a certain action and when it perceives another agent performing that action.
Motor control: The use of thinking to direct muscles and limbs to perform a desired action.
Nature: The genes that children bring with them to life and that influence all aspects of their development.
Null-hypothesis significance testing (NHST): In statistics, a test created to determine the chances that an alternative hypothesis would produce a result as extreme as the one observed if the null hypothesis were actually true.
Numerical magnitudes: The sizes of numbers.
Nurture: The environments, starting with the womb, that influence all aspects of children’s development.
Object permanence: The understanding that objects continue to exist even when they cannot be directly observed (e.g., that a pen continues to exist even when it is hidden under a piece of paper).
Object permanence task: The Piagetian task in which infants below about 9 months of age fail to search for an object that is removed from their sight and, if not allowed to search immediately for the object, act as if they do not know that it continues to exist.
Objective: Being free of personal bias.
Oppositional defiant disorder: A childhood behavior disorder that is characterized by stubbornness, hostility, and behavioral defiance. This disorder is highly comorbid with ADHD.
Parent management training: A treatment for childhood behavior problems that teaches parents how to use contingencies to more effectively manage their children’s behavior.
Pathologizes: To define a trait or collection of traits as medically or psychologically unhealthy or abnormal.
Phenotype: The pattern of expression of the genotype or the magnitude or extent to which it is observably expressed—an observable characteristic or trait of an organism, such as its morphology, development, biochemical or physiological properties, or behavior.
Phonemic awareness: Awareness of the component sounds within words.
Piaget’s theory: Theory that development occurs through a sequence of discontinuous stages: the sensorimotor, preoperational, concrete operational, and formal operational stages.
Population: In research, all the people belonging to a particular group (e.g., the population of left handed people).
Practice effect: When participants get better at a task over time by “practicing” it through repeated assessments instead of due to actual developmental change (practice effects can be particularly problematic in longitudinal and sequential research designs).
Preoperational reasoning stage: Period within Piagetian theory from age 2 to 7 years, in which children can represent objects through drawing and language but cannot solve logical reasoning problems, such as the conservation problems.
Probability: A measure of the degree of certainty of the occurrence of an event.
Probability values: In statistics, the established threshold for determining whether a given value occurs by chance.
Projection: A social perceiver’s assumption that the other person wants, knows, or feels the same as the perceiver wants, know, or feels.
Pseudoscience: Beliefs or practices that are presented as being scientific, or which are mistaken for being scientific, but which are not scientific (e.g., astrology, the use of celestial bodies to make predictions about human behaviors, and which presents itself as founded in astronomy, the actual scientific study of celestial objects. Astrology is a pseudoscience unable to be falsified, whereas astronomy is a legitimate scientific discipline).
Psychophysiological responses: Recording of biological measures (such as heart rate and hormone levels) and neurological responses (such as brain activity) that may be associated with observable behaviors.
Qualitative changes: Large, fundamental change, as when a caterpillar changes into a butterfly; stage theories such as Piaget’s posit that each stage reflects qualitative change relative to previous stages.
Quantitative changes: Gradual, incremental change, as in the growth of a pine tree’s girth.
Quantitative genetics: Scientific and mathematical methods for inferring genetic and environmental processes based on the degree of genetic and environmental similarity among organisms.
Recall memory: The process of remembering discrete episodes or events from the past, including encoding, consolidation and storage, and retrieval.
Representative: In research, the degree to which a sample is a typical example of the population from which it is drawn.
Research design: The strategy (or “blueprint”) for deciding how to collect and analyze research information.
Research methods: The specific tools and techniques used by researchers to collect information.
Sample: In research, a number of people selected from a population to serve as an example of that population.
Schemas: The gender categories into which, according to gender schema theory, children actively organize others’ behavior, activities, and attributes.
Scientific theory: An explanation for observed phenomena that is empirically well-supported, consistent, and fruitful (predictive).
Security of attachment: An infant’s confidence in the sensitivity and responsiveness of a caregiver, especially when he or she is needed. Infants can be securely attached or insecurely attached.
Sensorimotor stage: Period within Piagetian theory from birth to age 2 years, during which children come to represent the enduring reality of objects.
Sequential research designs: A research design that includes elements of cross-sectional and longitudinal research designs. Similar to cross-sectional designs, sequential research designs include participants of different ages within one study; similar to longitudinal designs, participants of different ages are followed over time.
Sex: Biological category of male or female as defined by physical differences in genetic composition and in reproductive anatomy and function.
Sexual harassment: A form of gender discrimination based on unwanted treatment related to sexual behaviors or appearance.
Sexual orientation: Refers to the direction of emotional and erotic attraction toward members of the opposite sex, the same sex, or both sexes.
Simulation: The process of representing the other person’s mental state.
Social brain: The set of neuroanatomical structures that allows us to understand the actions and intentions of other people.
Social learning theory: This theory of how children form their own gender roles argues that gender roles are learned through reinforcement, punishment, and modeling.
Social referencing: The process by which one individual consults another’s emotional expressions to determine how to evaluate and respond to circumstances that are ambiguous or uncertain.
Sociocultural theories: Theory founded in large part by Lev Vygotsky that emphasizes how other people and the attitudes, values, and beliefs of the surrounding culture influence children’s development.
Solidity principle: The idea that two solid masses should not be able to move through one another.
Strange situation: A laboratory task that involves briefly separating and reuniting infants and their primary caregivers as a way of studying individual differences in attachment behavior.
Synchrony: Two people displaying the same behaviors or having the same internal states (typically because of mutual mimicry).
Temperament: Early emerging differences in reactivity and self-regulation, which constitutes a foundation for personality development.
Theory of mind: The human capacity to understand minds, a capacity that is made up of a collection of concepts (e.g., agent, intentionality) and processes (e.g., goal detection, imitation, empathy, perspective taking).
Theory of mind: Children’s growing understanding of the mental states that affect people’s behavior.
Transgender: A term used to describe individuals whose gender does not match their biological sex.
Twin studies: A behavior genetic research method that involves comparison of the similarity of identical (monozygotic; MZ) and fraternal (dizygotic; DZ) twins.
Type I error: In statistics, the error of rejecting the null hypothesis when it is true.
Type II error: In statistics, the error of failing to reject the null hypothesis when it is false.
Value: Belief about the way things should be.
Verbal report paradigms: Research methods that require participants to report on their experiences, thoughts, feelings, etc., using language.
Vignette: A short story that presents a situation that participants are asked to respond to.
Violation of expectation paradigm: A research method in which infants are expected to respond in a particular way because one of two conditions violates or goes against what they should expect based on their everyday experiences (e.g., it violates our expectations that Wile E. Coyote runs off a cliff but does not immediately fall to the ground below).
Visual perspective taking: Can refer to visual perspective taking (perceiving something from another person’s spatial vantage point) or more generally to effortful mental state inference (trying to infer the other person’s thoughts, desires, emotions).
Voluntary responses: Behaviors that a person has control over and completes by choice.