Psychoanalysis
Object relations theory

Object relations theory attempts to explain human relationships through a study of how mental representations of the self and others are organized. The clinical symptoms that suggest object relations problems (typically developmental delays throughout life) include disturbances in an individual's capacity to feel: warmth, empathy, trust, sense of security, identity stability, consistent emotional closeness, and stability in relationships with significant others.

Klein discusses the concept of introjection, creating a mental representation of external objects; and projection, applying this mental representation to reality. Wilfred Bion introduced the concept of containment of projections in the mother-child relationship where a mother understands an infants projections, modifies them and returns them to the child.

Concepts regarding internal representation (aka 'introspect', 'self and object representation', or 'internalization of self and other'), although often attributed to Melanie Klein, were actually first mentioned by Sigmund Freud in his early concepts of drive theory (Three Essays on the Theory of Sexuality, 1905). Freud's 1917 paper " Mourning and Melancholia ", for example, hypothesized that unresolved grief was caused by the survivor's internalized image of the deceased becoming fused with that of the survivor, and then the survivor shifting unacceptable anger toward the deceased onto the now complex self-image.

Melanie Klein's hypotheses regarding internalization during the first year of life, leading to paranoid and depressive positions, were later challenged by René Spitz (e.g., The First Year of Life, 1965), who divided the first year of life into a coenesthetic phase of the first six months, and then a diacritic phase for the second six months. Mahler, Fine, and Bergman (1975) describe distinct phases and subphases of child development leading to "separation-individuation" during the first three years of life, stressing the importance of constancy of parental figures in the face of the child's destructive aggression, internalizations, stability of affect management, and ability to develop healthy autonomy.

During adolescence, Erik Erikson (1950–1960s) described the 'identity crisis', that involves identity-diffusion anxiety. In order for an adult to be able to experience "Warm-ETHICS: (warmth, Empathy, Trust, Holding environment, Identity, Closeness, and Stability) in relationships, the teenager must resolve the problems with identity and redevelop self and object constancy.
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