Nature versus nurture: do families cause mental illness?

  Whether you’re tall or short, whether you’re good at sport or hopeless, most of us believe this depends on a mixture of our genes (the biological potential we were born with) and our upbringing (our diet, exercise regime, even the sort of school we went to). Nothing controversial in that. The moment we mention psychology, however, the balloon goes up. Is IQ inherited or could everyone do just as well with the same opportunities? Is personality or criminality something we’re born with or can we change it? Can we avoid depression by healthy living? Few issues polarize us as much as how changeable we believe human behaviour to be. The disagreements are not just calm, academic ones but fuel (and are fuelled by) political and social beliefs reflecting fundamentally different worldviews.

  Psychiatry originally was very much at home in the ‘nature’ camp – mental illnesses ran in families and were inherited weaknesses. It was our job to ameliorate them and make life as bearable as possible, hoping for a speedy recovery. Freud and his followers began to change all that, shifting the balance to ‘nurture’. Psychoanalysis is firmly based on the belief that what happens to us in early life, and the memory of those experiences, is the cause of many illnesses. Even more convincing, Freud showed that addressing those memories could cure some mental illnesses. So an individual’s personal history (their ‘narrative’) wasn’t just the context for understanding their illness but possibly its origin.

  Psychoanalysis dominated psychiatric thinking and training from the 1940s to the 1970s. The attraction of psychoanalysis to the Americas should come as no shock. After all, these societies were established by those who escaped the pessimistic fatalism of Europe with its fixed social orders and hereditary monarchies and aristocracies. Those who moved west were those who rejected this and grasped the opportunity for each individual to shape their own future. No surprise then that they espoused a psychology that enshrined this capacity for growth, where the individual could overcome early limitations and forge their own destiny. The role of nurture and experience was strengthened by observations of battle trauma in both world wars (Chapter 3). The revelation of the eugenic and racist policies of Nazi Germany (including the liquidation of ‘genetically inferior’ psychiatric patients) finally guaranteed nurture’s moral unassailability.

  An attraction of emphasizing nurture is that it holds out much greater possibility of cure. If mental illnesses are essentially caused by relationships then they should be curable by relationships (i.e. psychotherapy). However, the downside of this approach is its potential for blame – in particular blaming parents. Freud himself quickly realized these risks when he began to suspect that the reported sexual abuse by parents (which he originally considered the cause of his patients’ neuroses) might be fantasies. The great German psychopathologist and philosopher Jaspers pointed out that, while understanding the personal relevance of symptoms was essential in psychiatry, it was not the same as understanding what caused the illness. Such fine distinctions have not, however, generally characterized this debate publically.