Distress when a familiar caregiver or loved one leaves; most obvious between 9 and 14 months.

An infant's expression of concern—a quiet stare while clinging to a familiar person, or a look of fear—when a stranger appears.

A person's realization that he or she is a distinct individual whose body, mind, and actions are separate from those of other people.

Inborn differences between one person and another in emotions, activity, and self-regulation. It is measured by the person's typical responses to the environment.

A coordinated, rapid, and smooth exchange of responses between a caregiver and an infant.

According to Ainsworth, "an affectional tie" that an infant forms with a caregiver—a tie that binds them together in space and endures over time.

A relationship in which an infant obtains both comfort and confidence from the presence of his or her caregiver.

A pattern of attachment in which an infant avoids connection with the caregiver, as when the infant seems not to care about the caregiver's presence, departure, or return.

A pattern of attachment in which an infant's anxiety and uncertainty are evident, as when the infant becomes very upset at separation from the caregiver, such infants both resist and seek contact on reunion.

A type of attachment that is marked by an infant's inconsistent reactions to the caregiver's departure and return.

A laboratory procedure for measuring attachment by evoking infants' reactions to the stress of various adults' comings and goings in an unfamiliar playroom.

Seeking information about how to react to an unfamiliar or ambiguous object or event by observing someone else's expressions and reactions. That other person becomes a social reference.

Literally, "other-care"; the care of children by people other than the biological parents.

Erikson's first crisis of psychosocial development. Infants learn basic trust if the world is a secure place where their basic needs (for food, comfort, attention, and so on) are met.

Erikson's second crisis of psychosocial development. Toddlers either succeed or fail in gaining a sense of self-rule over their actions and their bodies.

Caregiving practices that involve being physically close to the baby, with frequent holding and touching.

Caregiving practices that keep some distance from a baby, such as providing toys, food, and face-to-face communication with minimal holding and touching.

2nd state: 1-3: Anus focus of pleasure & toilet training most important activity

Erikson's first stage during the first year of life, infants learn to trust when they are cared for in a consistent warm manner

Erikson's stage in which a toddler learns to exercise will and to do things independently; failure to do so causes shame and doubt