Sistema basado en el conocimiento y prototipo computacional

In §2.3.2, I presented medically unexplained syndromes as paradigmatic cases of

diagnoses that are widely considered not to provide explanations of patients’ symptoms and laid out some of the broader implications of their explanatory shortcomings. It may be apparent that some of the sorts of property that are associated with the explanatory shortcomings of medically unexplained syndrome diagnoses are also shared by psychiatric diagnoses, such as syndromic definitions based on symptom clusters, exclusion criteria

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that recommend ruling out possible medical causes before the diagnoses are established, and contentions regarding the precise causal structures of the disorders. Given these similarities and the potential associated implications, more detailed investigation is warranted regarding whether or not psychiatric diagnoses actually do provide

explanations of patients’ symptoms. I do not intend to fully answer this question in the current chapter, as the rest of the thesis is dedicated to this task. Rather, I would like here to highlight some of the critiques of psychiatric diagnoses that are related to their

uncertain explanatory statuses, in order to further support the point made in Chapter 1, §1.2.1, that the question of whether or not psychiatric diagnoses genuinely function as explanations of symptoms has significant implications for clinical discourse and practice.

Like medically unexplained syndromes, psychiatric disorders have historically been beset by controversies. Among the most famous of those sceptical of psychiatric

disorders are the proponents of the antipsychiatry movement of the 1960s. We have already visited Thomas Szasz (1960) in Chapter 1, who criticises the concept of mental illness. First, he argues that mental illness cannot legitimately be invoked as an

explanation of someone’s behaviour because it is merely a shorthand label for the behaviour. Second, he argues that mental illness is not determined by a physiological cause, but by moral and social norms. Other antipsychiatrists offer different critiques of psychiatry. For example, Michel Foucault ([1961] 1964) argues that our current ways of thinking about psychiatric disorders as medical problems are the products of contingent historical developments, and so it is possible that these current ways of thinking might not have arisen had history worked out differently, while R. D. Laing (1967), criticises the medical conception of schizophrenia and instead argues that it is a normal and

understandable response to an existentially distorted social world.

Szasz’s (1961) critique is noteworthy, because it draws connections between the supposed illegitimacy of a psychiatric diagnosis qua causal explanation and shortcomings

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with respect to its normative and social functions. That is to say, he uses his argument that mental illness diagnoses fail to explain people’s behaviours to support the normative claim that mental illnesses are not genuine medical disorders and also to oppose the sanctioned uses of involuntary treatments for mental illnesses. This sort of approach has also been used by proponents of the subsequent critical psychiatry movement. David Ingleby (1982) argues that psychiatric diagnoses are only allowed to instigate the social responses of mobilising clinical resources and sanctioning certain behaviours because they are presented by the psychiatric profession as designating diseases that are

responsible for the patients’ symptoms, much like diagnoses in other medical specialties. However, the suggestion is that psychiatric diagnoses do not designate genuine diseases that explain the symptoms, and so such social responses are not justified. Hence, Ingleby suggests that if people are made aware that the diagnoses instigate social responses that are not supported by medical explanations, then “questions would immediately arise about the propriety of those responses” (Ingleby, 1982: p. 137). Similarly, Joanna Moncrieff (2010) suggests that the notion that psychiatric diagnoses pick out underlying diseases that cause symptoms is just an assumption and that challenging this assumption could open up the associated social responses to scrutiny.

Writing from an analytic philosophy, rather than a social theory, point of view, Jeffrey Poland (2014) criticises the epistemic shortcomings of the psychiatric diagnoses in the DSM:

The DSM categories and associated epistemic practices related to information processing, inferential practice, explanatory practice, and clinical understanding, are ineffective and harmfully biased because, given their atheoretical focus on clinical phenomenology, they do not effectively identify and represent important features, problems, contexts, and processes … (i.e., they do not underwrite sound clinical

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inferences and judgments concerning what is wrong and what is likely to be helpful). (Poland, 2014: p. 48)

Poland’s critique suggests that explanatory failure is connected to other shortcomings regarding classification, prediction, and intervention. That is to say, psychiatric diagnoses that do not adequately inform us about the processes underlying patients’ problems are poor categories that are unlikely to support reliable inferences or guide effective

treatment decisions. He describes such diagnoses as “free riders” that contribute little over and above descriptions of symptoms (Poland, 2014: p. 34).

Moncrieff (2010) also argues that causal explanatory shortcomings are associated with limitations regarding therapeutic interventions in psychiatry. She writes:

In contrast to most medical conditions like diabetes, tuberculosis and heart disease, no psychiatric condition can be traced to a specific dysfunctional bodily process … There is no evidence that any class of psychiatric drug acts by reversing or partially reversing an underlying physical process that is responsible for producing

symptoms … Therefore the idea that the behaviours seen by psychiatrists are indicative of an underlying disease is simply an assumption. (Moncrieff, 2010: p. 373)

Of course, whether or not psychiatric conditions can be traced to specific processes and whether or not psychiatric drugs do act by reversing specific processes are empirical questions that require empirical support. I reserve detailed examination of the empirical data relevant to the former question for Chapter 5. Nonetheless, a more modest point can still be gleaned from the above critique. If it is the case that a psychiatric diagnosis does not provide a causal explanation for a cluster of symptoms, then such a diagnosis

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cannot be said to supply a justification for a given treatment for the disorder on the basis of the supposition that the treatment acts by interfering with a particular causal process. Furthermore, there is a sense in which such a treatment would be palliative. Given the lack of knowledge regarding whatever causal process might be underlying the cluster of symptoms, it would seem that only the cluster of symptoms itself, but not any underlying causal process, would be a tangible target for therapeutic intervention.

To sum up, there are controversies regarding the explanatory roles of psychiatric diagnoses. The above critiques show some of the ways in which potential explanatory shortcomings could limit or delegitimise the roles of psychiatric diagnoses in sanctioning certain social responses, predicting clinical outcomes, and guiding therapeutic

interventions. Given these controversies and the potential implications for psychiatric practice, it is important to pursue a better understanding of what sorts of explanatory role, if any, are served by diagnoses in psychiatry.