DOUBLE BIND: A STUDY OF TWO PAIRS OF FEMALE MONOZYGOTIC TWINS CONCORDANT FOR ANOREXIA NERVOSA Patricia Marsden and J. Hubert Lacey ABSTRACT The cases of two pairs of female monozygotic twins concordant for anorexia nervosa are considered in order to explore the interrelationship between the psychodynamics of the twin relationship and the psychopathology of anorexia. It is suggested that twins face a dual task of separation-individuation - from mother and from the other twin - and that separation- individuation between monozygotic twins presents particular difficulties. Anorexia nervosa may represent an attempt to avoid separation by means of a retreat to a pre-adolescent state in which differences, envy and rivalry can be denied. Without my shadow would I die? Without my shadow would I gain life? Be free or left to die? June Gibbons (Wallace 1987, p. 231) Introduction For many people, twins, and especially `identical' twins, hold a particular fascination. We wonder how it would be to share so much with another human being - even to have shared the space of the womb - never to have been alone from the first moments of becoming human. We may envy twins their closeness, imagining that they share their most intimate feelings and thoughts in mysterious ways, that they have a mutual resonance that transcends words. Such perceptions of what it is to be a twin seem to be confirmed by some stories from myth such as that of Castor and Pollux. These twins were conceived when Jupiter, in the guise of a swan, seduced Leda. She gave birth to an egg from which sprang the twins who were later famed for being `united by the warmest affection and inseparable in all their enterprises' (Bulfinch 1981, p. 188). When, eventually, Castor was killed, Pollux refused immortality unless his twin could share it with him. Jupiter's solution of their spending alternate days under the earth and in heaven allowed them to avoid separation even in death. PATRICIA MARSDEN is senior psychotherapist with the St George's Eating Disorders Service, London, and honorary research assistant at St George's Hospital Medical School. She is a psychotherapy member of the Foundation for Psychotherapy and Counselling and is in private practice. J. HUBERT LACEY MD, M Phil., FRCPsych. is Professor of Psychiatry, University of London, and consultant in charge of St George's Eating Disorders Service. Address for correspondence: Patricia Marsden, Eating Disorders Research Team, Dept. of Psychiatry, St George's Hospital Medical School, Cranmer Terrace, London SW17 ORE. [email: pmarsden@sghms.ac.uk] British Journal of Psychotherapy, Vol 16(2), 1999 © The author