The Small World of Psychopathology

Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands.
PLoS ONE (Impact Factor: 3.23). 11/2011; 6(11):e27407. DOI: 10.1371/journal.pone.0027407
Source: PubMed


Mental disorders are highly comorbid: people having one disorder are likely to have another as well. We explain empirical comorbidity patterns based on a network model of psychiatric symptoms, derived from an analysis of symptom overlap in the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV).
We show that a) half of the symptoms in the DSM-IV network are connected, b) the architecture of these connections conforms to a small world structure, featuring a high degree of clustering but a short average path length, and c) distances between disorders in this structure predict empirical comorbidity rates. Network simulations of Major Depressive Episode and Generalized Anxiety Disorder show that the model faithfully reproduces empirical population statistics for these disorders.
In the network model, mental disorders are inherently complex. This explains the limited successes of genetic, neuroscientific, and etiological approaches to unravel their causes. We outline a psychosystems approach to investigate the structure and dynamics of mental disorders.

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    Sexologies 01/2016; (Accepté). DOI:10.1016/j.sexol.2015.08.001
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    • "One important drawback of this model is that it does not assume associations between the individual symptoms, whereas this does seem plausible (e.g. sleep problems leading directly to concentration problems (Borsboom et al. 2011). It has been suggested that the structure of psychopathology may be better described as a complex network of components that interact in dynamic and nonlinear ways both at biological (Buckholtz & Meyer-Lindenberg, 2012) and psychological (Kendler et al. 2011) levels. "
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    • "Related work has shown that the DSM symptom network con - forms to what can be called a small world structure : the DSM features a host of interrelated symptoms , and symptoms are strongly connected both within and across diagnoses . This means that one can " travel " from any symptom to any other symptom in just a few jumps ( Borsboom et al . , 2011 ; Goekoop and Goekoop , 2014 ) , a perspective that offers new possibilities for comorbidity research ."
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