Child Development

mother-child separation. He completed a mono-
graph for the World Health Organization on the sad
fate of homeless children in postwar Europe and col-
laborated with James Robertson on a film, A Two-
Year-Old Goes to the Hospital. These works drew the at-
tention of child clinicians to the potentially
devastating effects of maternal separation, and led to
the liberalization of family visiting privileges for hos-
pitalized children.

Unsatisfied with the psychoanalytic view that the
child’s love of mother derived from oral gratification,
Bowlby embraced the ethological theories of Konrad
Lorenz and Niko Tinbergen, which stress the evolu-
tionary foundations of behavior as a source of expla-
nation for mother-child attachment relationships. He
presented his first formal statements of ethologically
based attachment theory to the British Psychoanalytic
Society in 1957. Bowlby argued that mother-child at-
tachment has an evolutionary basis, promoting the
child’s survival by increasing mother-child proximity,
particularly when the child is stressed or fearful. The
mother thus serves as a secure base for the young
child’s exploration of the world. Bowlby expanded his
theory of attachment in his Attachment and Loss trilogy
(volume 1: Attachment, volume 2: Separation, and vol-
ume 3: Loss). Bowlby’s theory was supported by the
empirical work of his collaborator, Mary Dinsmore
Salter Ainsworth, who examined the normative devel-
opment of attachment relationships across cultures as
well as the maternal care-giving patterns that predict
individual differences in the quality of mother-infant
attachment security.

Controversial at first, attachment theory became
a dominant principle of social and personality devel-
opment by the 1980s, generating thousands of re-
search papers and serving as a theoretical basis for
clinical intervention programs. After his retirement
in 1972, Bowlby continued to develop the clinical ap-
plication of attachment theory. He completed a biog-
raphy of Charles Darwin shortly before his death in
1990.

Bibliography
Bretheron, Inge. ‘‘The Origins of Attachment Theory: John
Bowlby and Mary Ainsworth.’’ Developmental Psychology 28
(1992):759–775.
Holmes, Jeremy. John Bowlby and Attachment Theory. London: Rout-
ledge, 1993.

Publications by Bowlby
Maternal Care and Mental Health. Geneva: World Health Organiza-
tion, 1946.
‘‘The Nature of the Child’s Tie to His Mother.’’ International Jour-
nal of Psychoanalysis 39 (1958):1–23.
Attachment and Loss, Vol. 1: Attachment. New York: Basic Books,
1968.
Attachment and Loss, Vol. 2: Separation, Anxiety, and Anger. London:
Penguin Books, 1973.

English psychiatrist John Bowlby argued that mother-child

attachment has an evolutionary basis. (Bill Varie)

Attachment and Loss, Vol. 3: Loss: Sadness and Depression. New York:

Basic Books, 1980.

Bowlby, John, James Robertson, and Dina Rosenbluth. ‘‘A Two-

Year-Old Goes to the Hospital.’’ Psychoanalytic Study of the

Child 7 (1952):82–74.

Nancy Hazen

BRAIN DEVELOPMENT

The development of the human brain occurs rapidly

in the first years of life and continues at a slower pace

into adolescence. The major steps involved in brain

development, both before and after birth, play im-

portant roles in psychological development.

The Cerebral Cortex

The cerebral cortex is a thin, flat sheet of cells at

the outer surface of the brain. Understanding the de-

velopment of this part of the brain is important for

understanding psychological development, as it is

BRAIN DEVELOPMENT 65