Psychiatric researchers typically assume that the modelling of psychiatric symptoms is not influenced by psychiatric categories; symptoms are modelled and then grouped into a psychiatric category. I highlight this primarily through analysing research domain criteria (RDoC). RDoC’s importance makes it worth scrutinizing, and this assessment also serves as a case study with relevance for other areas of psychiatry. RDoC takes inadequacies of existing psychiatric categories as holding back causal investigation. Consequently, RDoC aims to circumnavigate existing psychiatric categories by directly investigating the causal basis of symptoms. The unique methodological approach of RDoC exploits the supposed lack of influence of psychiatric categories on symptom modelling, taking psychiatric symptoms as the same regardless of which psychiatric category is employed or if no psychiatric category is employed. But this supposition is not always true. I will show how psychiatric categories can influence symptom modelling, whereby identical behaviours can be considered as different symptoms based on an individual’s psychiatric diagnosis. If the modelling of symptoms is influenced by psychiatric categories, then psychiatric categories will still play a role, a situation which RDoC researchers explicitly aim to avoid. I discuss four ways RDoC could address this issue. This issue also has important implications for factor analysis, cluster analysis, modifying psychiatric categories, and symptom based approaches.

No abstract

Kanner opens his pioneering 1943 paper on autism by making a mysterious mention of the year 1938. Recent letters to the editor of this journal have disagreed over a particular interpretation-does 1938 refer to an early paper by Asperger, effectively meaning Kanner plagiarised Asperger? I argue 1938 refers to a paper by Louise Despert. This was not plagiarism but a case of building on Despert's ideas. Additionally, I suggest his motives for not mentioning her by name were not dishonourable.

Forthcoming in the British Journal for the Philosophy of Science Some critics argue that the type of psychiatric diagnosis found in the DSM and ICD are superfluous and should be abandoned. These are known as categorical polythetic psychiatric diagnoses. To receive a categorical polythetic psychiatric diagnosis an individual need only exhibit some, rather than all, of the symptoms on the diagnostic criteria. Consequently, categorical polythetic psychiatric diagnoses only associate an individual with a range of symptoms rather than specify which symptoms they have. Drawing upon Ronald Giere's account of scientific models, I portray categorical polythetic psychiatric diagnoses as abstract models which guide the building of less abstract models.These models can specify which symptoms a particular individual has.Additionally, categorical polythetic psychiatric diagnoses can guide investigation of symptoms towards difficult to spot symptoms, guide investigation towards changing symptoms and guide investigation towards how symptoms manifest. These important roles mean categorical polythetic psychiatric diagnoses should not be abandoned. assist accurately detecting symptoms 4.2 Advantage two: Categorical polythetic psychiatric diagnoses can assist with detecting changing symptoms 4.3 Advantage three: Categorical polythetic psychiatric diagnoses can associate symptoms with more specific behaviour 5 Broadening The Argument Beyond ASD

Critics who are concerned over the epistemological status of psychiatric diagnoses often describe them as being constructed. In contrast, those critics usually see symptoms as relatively epistemologically unproblematic. In this paper I show that symptoms are also constructed. To do this I draw upon the demarcation between data and phenomena. I relate this distinction to psychiatry by portraying behaviour of individuals as data and symptoms as phenomena. I then draw upon philosophers who consider phenomena to be constructed to argue that symptoms are also constructed. Rather than being ready made in the world I show how symptoms are constructs we apply to the world. I highlight this with a historical example and describe methodological constraints on symptom construction. I show the epistemic problems with psychiatric diagnoses are also applicable to symptoms. Following this, I suggest that critics of psychiatric diagnoses should extend their criticism to symptoms or, if they still believe symptoms are relatively epistemologically unproblematic, should rethink their concerns over psychiatric diagnoses.