The Boundary Problem in Psychiatry
What is essentially a valid boundary problem in psychiatry – At what point does everyday sadness become Depression? When exactly does ordinary apprehension become an Anxiety disorder? – is often conflated by psychiatry critics with the question of legitimacy to generate the erroneous conclusion that all of what is considered as psychopathology is in reality normal human experience.
The boundary problem plagues all medical conditions in which the underlying process exhibits a continuity. For instance, consider Hypertension and Diabetes. At what measurement does blood pressure become pathological? At what reading does blood sugar level become pathological? (These measurements, like many other physiological attributes, have a bell-shaped Gaussian distribution in a human population, and most likely, so does mood.) Our current criteria are rather arbitrarily set, utilizing available data to make a judgement as to at what blood pressure or blood sugar reading does the risk of adverse effects becomes significant enough to warrant treatment. These criteria have been revised with time and have been modified in the presence of co-morbidities (such as the criteria for Hypertension is lower in patients of Diabetes). However, on the basis of this alone, it would be absurd to suggest that Hypertension or Diabetes is a medicalization of what is otherwise a normal state of being. Yet this is precisely the argument many employ against psychiatry. Just because the boundaries between the normal and pathological are fuzzy, it does not mean that there is no underlying pathology at all. Yes, it may be said that these boundaries in psychiatry as currently practised are established on insufficient evidence or that the criteria have been set in a manner that makes them vulnerable to abuse by pathologizing natural anxieties, and that would be a justified criticism, but it would be unreasonable to conclude that the condition in itself is a sham diagnosis.
(Some thoughts after reading the review of All We Have to Fear: Psychiatry's Transformation of Natural Anxieties into Mental Disorders at LARB.)