Psychosocial Development

Temperament

The innate characteristics of an infant — including mood, activity level, and emotional reactivity — noticeable soon after birth.

New York Longitudinal Study

Chess and Thomas's 1956 landmark study that evaluated 141 children's temperament through parental interviews across 9 dimensions.

Easy Child (temperament)

About 40% of children — adapts quickly to routine/new situations, remains calm, easy to soothe, usually positive mood.

Difficult Child (temperament)

About 10% of children — reacts negatively to new situations, struggles to adapt to routine, usually negative mood, cries frequently.

Slow-to-Warm-Up Child (temperament)

About 15% of children — low activity level, adjusts slowly to new situations, often negative mood.

Goodness-of-Fit

When a caregiver's style matches a child's temperament, allowing communication and interaction to flow smoothly.

Temperament vs. Personality

Temperament is innate and stays fairly stable; personality is a broader, evolving pattern of feeling/thinking/behaving shaped by temperament plus experience.

Basic Emotions

Emotions that appear first in development: interest, happiness, anger, fear, surprise, sadness, and disgust.

Self-Conscious Emotions

Emotions requiring a self-concept and social instruction, such as envy, pride, shame, guilt, doubt, and embarrassment.

Stranger Wariness

Fear associated with the presence of an unfamiliar person, appearing between 6-15 months, after object permanence develops.

Separation Anxiety

Fear/distress associated with the departure of significant others (caregivers), appearing between 6-15 months.

Social Referencing

The process by which infants seek out information from others (like facial expressions) to clarify an ambiguous situation and then use that info to act.

Emotional Self-Regulation

Strategies used to control one's emotional states in order to attain goals; initially requires caregiver assistance.

Self-Awareness

The realization that you are separate from others; develops between 15-24 months (tested via the rouge/mirror experiment).

Attachment

The close bond with a caregiver from which an infant derives a sense of security.

Freud's attachment theory

Infants become attached to whoever satisfies their oral needs (e.g., feeding), typically the mother.

Contact Comfort

An infant's need for physical closeness and touching, shown by Harlow's monkey studies to be the true foundation of attachment (not just food).

Bowlby's Attachment Theory

Attachment is the affectional bond an infant forms with a primary caregiver; requires caregiver responsiveness and mutually enjoyable interactions.

Secure Base

A parental presence that gives a child a sense of safety as they explore their surroundings (Bowlby).

Strange Situation Technique

Mary Ainsworth's laboratory procedure that measures an infant's attachment style by observing behavior in an unfamiliar context, especially during caregiver separation/reunion.

Secure Attachment

Approximately 65% of US children — explores freely with caregiver present, may be upset when caregiver leaves, and happy when caregiver returns.

Ambivalent (Resistant) Attachment

Approximately 10-15% of US children — wary/clingy, extremely distressed when caregiver leaves, hard to soothe or may resist comfort upon return.

Avoidant Attachment

Approximately 20% of US children — avoids/ignores caregiver, shows little emotion when caregiver leaves or returns.

Disorganized/Disoriented Attachment

Approximately 5-10% of US children — inconsistent coping (may cry then avoid caregiver, or approach then freeze); most insecure style.

Non-Organic Failure to Thrive

A diagnosis for an infant who fails to grow/gain weight on schedule with no known medical cause; linked to poverty, neglect, inconsistent parenting.

Reactive Attachment Disorder

A DSM-5-TR diagnosis following neglect, marked by disturbed attachment behavior — inhibited, withdrawn, minimal social/emotional responsiveness. Occurs in under 10% of severely neglected children.

Resiliency

The ability to overcome challenges and successfully adapt, linked to factors like an easy-going temperament and strong external support.

Erikson: Trust vs. Mistrust

Infancy's psychosocial crisis (birth-18 months) — consistent caregiving builds a sense that the world is trustworthy.