Psychogenic Explanations of Physical Illness: Time to Examine the Evidence
Carolyn E. Wilshire and Tony Ward, Victoria University of Wellington, Wellington, New Zealand
In some patients with chronic physical complaints, detailed examination fails to identify a well-recognized
underlying disease process. In this situation, the physician may suspect a psychological cause. This review
critically evaluates the evidence for this causal claim, focusing on complaints presenting as neurological
disorders. There were four main conclusions. First, patients with these complaints frequently exhibit
psychopathology, but not consistently more often than patients with a comparable “organic” diagnosis, so a
causal role cannot be inferred. Second, these patients report a high incidence of adverse life experiences, but
again, this evidence is insufficient to infer causation: A psychogenic diagnosis is likely to prompt careful
reexamination of negative past experiences, thereby introducing a recall bias. Third, although psychogenic
illnesses are believed to be more responsive to psychological interventions than comparable “organic” illnesses,
there is currently no evidence to support this claim. Finally, recent evidence suggests that biological and
physical factors play a much greater causal role in these illnesses than previously believed. We conclude that
there is currently little evidential support for psychogenic theories of illness in the neurological domain. Future
research needs to take a wider view concerning the etiology of these illnesses.
