John Bowlby, 83, a noted British psychiatrist and psychoanalyst who conducted groundbreaking investigations on the emotional links between mothers and children, died Sept. 2 at his vacation home on Scotland's Isle of Skye after a stroke.

He is best known for his work in "attachment theory," which observes and attempts to explain the emotional cost to a young child when the bonds with a mother are broken. This theory was examined in his trilogy, "Attachment and Loss." The first volume, "Attachment," appeared in 1969, followed by "Separation" in 1973 and "Loss" in 1980.

His work characterized the bond between mother and child as both instinctive and more important than popularly believed. He said that separation of mother and child could lead to such problems in children as depression and chronic delinquency.

After World War II, he conducted studies of children orphaned by the conflict who grew up in orphanages. He reported on the debilities suffered by large numbers of these children.

Dr. Bowlby used theories that he drew from earlier animal studies to explain some of these problems and to challenge some of the basic laws of child psychiatry. His first major work, "Fourty-four Juvenile Thieves," published in 1946, examined a group of very young London criminals. It found that the one common denominator in the group was prolonged separation between the offenders and their mothers.

This coincided with research in this country with young monkeys. Separated from their mothers, they were found to be depressed, seemed socially isolated, and had difficulty mating.

His work also led to a British film study of children hospitalized and kept from their mothers. The films dramatically illustrated children's anger and depression at the deprivation.

Over the years, Dr. Bowlby's work, though still controversial, has resulted in many changes. His work was often cited in public policies that result in children being left in "bad" homes rather than being put in "good" institutions. The work is also responsible for hospitals making it easier for mothers to spend greater amounts of time with a child when either is hospitalized.

Dr. Bowlby has been criticized by feminist groups for allegedly chaining women to children and fostering guilt in women. However, Dr. Bowlby maintained that his work was miscontrued by some and that he was not addressing the working mother. He said that a mother's absence for work does not harm the child if adequate provision is made for day care.

Though he clashed throughout his career with other noted analysts, including Anna Freud, his work has met increasing acceptance. He had been a consultant to the World Health Organization since 1950, and was a consultant to the National Institute of Mental Health in the United States from 1958 to 1963. He held a variety of high scientific awards from organizations in this country and Britain. He was made a commander of the British Empire in 1972.

Edward John Mostyn Bowlby was born in London. His father, Sir Anthony A. Bowlby, served as president of the Royal College of Surgeons in the early 1920s. Dr. Bowlby attended the Royal Naval College at Dartmouth in England and Cambridge University's Trinity College, where he received a master's degree in natural sciences and psychology. He graduated from the University of London's medical college.

During World War II, he was a psychiatrist in the Royal Army Medical Corps and attained the rank of lieutenant colonel. In 1946, he joined the staff of Tavistock Clinic in London. It is one of Britain's leading institutions of psychiatric research and treatment. He was chairman of the clinic's children and parents department until 1968 and retired from the clinic in 1972. Since that time, he had been a senior research fellow there.

Dr. Bowlby was the author of the 1953 bestseller, "Child Care and the Growth of Love," an indictment of institutionalization. His most recent book, "Charles Darwin: A New Biography," published earlier this year in Britain, examines Darwin's life in the light of his childhood.

Dr. Bowlby's survivors include four children and seven grandchildren.