Concept of representation and mental symptoms. The case of theory of mind.

Background: Most current theories explaining theory of mind (ToM) rely on the concept of 'representation', as it is usually employed in cognitive science, and is thus affected by its epistemic shortcoming, namely its incapacity to use 'sub-signifier' level information. This shortcoming is responsible for the lack of specificity of ToM deficits, which are now found in very different syndromes, from schizophrenia to bipolar disorder or borderline personality disorder, in spite of its original formulation being restricted to childhood autism.
Method: Representation, its shortcomings and the way they may affect clinical/research programs undergo a conceptual analysis, which shows how representational-founded semiology leave out information that is essential for symptom specificity and correct symptom assessment. Schizophrenic autism, delusional perception and axial syndromes are studied as examples of both the difficulties that have arisen and possible ways of dealing with them.
Results: Transfers of properties between different meanings of 'representation' together with a systematic ambiguity in the use of 'representation' are proposed as the main ways for representational approaches to assure stability to their proposals in spite of the violence exerted on clinical phenomena.
Conclusions: It is exposed how systematic ambiguity and epistemic shortcomings both affect Leslie's formulation of ToM and, further, the importance of these characteristics of the concept of 'representation' for general issues in psychiatric semiology.
(2009 S. Karger AG, Basel.)