- Multiple cultural variables have effects on the psychobiology and behavioral manifestations of illness, as do patient and physician perceptions of illness. The interaction among these variables is at the heart of clinical psychiatry. This case of a Vietnamese man with selective mutism underscores the relevance of the 'cultures' of medicine, psychiatry, and war and trauma on the manifestations of illness and illness perceptions by patient and physician. The discussion focuses on how these cultures interact and play a crucial role in formulating diagnosis and treatment planning. Suggestions are given for shifts in medical education that will encourage relevant cultural paradigms to make their way into educational and clinical systems, which in turn should improve cultural competence in clinical psychiatry.