Development
Changes in behavior or abilities or both.
Nature-Nurture Issue
The degree to which biology (nature) or the environment (nurture) contributes to a person’s development.
Zygote
A fertilized egg.
Germinal Stage
The first stage of prenatal development, from conception to 14 days. Cells travel to the uterus.
Embryonic Stage
The second stage of prenatal development, lasting from the 3rd through the 8th week. Major characteristic of this stage is the formation and development of the major organs and systems.
Fetal Stage
The third stage of prenatal development from the 9th week through the 9th month. Major characteristic is continued growth and maturation.
Down Syndrome
A genetic birth disorder resulting from an extra 21st chromosome, characterized by distinct facial features and a greater likelihood of heart defects and intellectual disability.
Teratogen
An environmental substance that has the potential to harm the developing organism.
Sensitive Period
In prenatal development, a time when genetic and environmental agents are most likely to cause birth defects.
Fetal Alcohol Syndrome
A birth condition resulting from the mother’s chronic use of alcohol during pregnancy that is characterized by facial and limb deformities and intellectual disability.
Neonate
A newborn during the first 28 days of life.
Reflex
An automatic response to a specific environmental stimulus.
Gross Motor Skills
Motor behaviors, involving the large muscles of the body such as running, walking, jumping, and hopping.
Fine Motor Skills
Motor behaviors involving the small muscles of the body such as writing, using utensils, and playing an instrument.
Cognition
The ability to think, know, and remember.
Schema
A mental idea, concept, or thought.
Assimilation
The process by which an existing schema is used to understand something new in the environment.
Accommodation
The process by which a schema is changed, modified, or created anew in order to understand something new in the environment.
Sensorimotor Stage
Piaget’s first stage of cognitive development, in which infants learn schemas through their senses and motor abilities.
Object Permanence
The understanding that an object continues to exist even when it is not present.
Symbolic Thinking
The understanding that objects can be represented with symbols such as bodily gestures or language.
Preoperational Stage
Piaget’s second stage of cognitive development characterized by the use of symbols and illogical thought.
Centration
The act of focusing on only one aspect or feature of an object.
Conservation
The understanding that an object retains its original properties even though it may look different.
Egocentrism
The belief that everyone thinks as you do.
Concrete Operation
Piaget’s third stage of cognitive development, characterized by logical thought.
Private Speech
Vygotsky’s term describing the behavior of young children who talk to themselves to guide their own actions.
Zone of Proximal Development
According to Vygotsky, the gap between what a child is already able to do and what he or she is not yet capable of doing without help.
Scaffolding
A process in which adults initially offer guidance and support in helping a child to reason, solve a problem, or master a task; as the child becomes more proficient and capable, the adult helps less and less until the child can master the task on his or her own.
Moral Reasoning
How you decide what is right and what is wrong.
Temperament
A person’s general pattern of attention, arousal, and mood that is evident at birth.
Attachment
The emotional bond between caretaker and infant that is established by 8 to 9 months.
Separation Anxiety
The fear an infant expresses when separated from the primary caretaker.
Stranger Anxiety
The distress an infant expresses when faced with unfamiliar people.
Authoritarian Parent
A parenting style characterized by high levels of control and low levels of affection.
Authoritative Parent
A parenting style characterized by moderate levels of control and affection.
Permissive Parent
A parenting style characterized by low levels of control or discipline.
Imaginary Audience
The belief held by adolescents that everyone is watching what they do.
Personal Fable
The belief held by adolescents that they are unique and special. May contribute to the risks taken by adolescents.
Dualistic Thinking
Reasoning that divides situations and issues into right and wrong categories.
Relativistic Thinking
The idea that in many situations there is not necessarily one right or wrong answer.
Postformal Thought
The idea that a correct solution (or solutions) may vary, depending on the circumstances.
Fluid Intelligence
Abilities that rely on information-processing skills such as reaction time, attention, and working memory.
Crystallized Intelligence
Abilities that rely on knowledge, expertise, and judgment.