Intentional content in psychopathologies requires an expanded interpretivism

The Network Theory of Psychiatric Disorders: A Critical Assessment of the Inclusion of Environmental Factors

Borsboom and colleagues have recently proposed a "network theory" of psychiatric disorders that conceptualizes psychiatric disorders as relatively stable networks of causally interacting symptoms. They have also claimed that the network theory should include non-symptom variables such as environmental factors. How are environmental factors incorporated in the network theory, and what kind of explanations of psychiatric disorders can such an "extended" network theory provide? The aim of this article is to critically examine what explanatory strategies the network theory that includes both symptoms and environmental factors can accommodate. We first analyze how proponents of the network theory conceptualize the relations between symptoms and between symptoms and environmental factors. Their claims suggest that the network theory could provide insight into the causal mechanisms underlying psychiatric disorders. We assess these claims in light of network analysis, Woodward's interventionist theory, and mechanistic explanation, and show that they can only be satisfied with additional assumptions and requirements. Then, we examine their claim that network characteristics may explain the dynamics of psychiatric disorders by means of a topological explanatory strategy. We argue that the network theory could accommodate topological explanations of symptom networks, but we also point out that this poses some difficulties. Finally, we suggest that a multilayer network account of psychiatric disorders might allow for the integration of symptoms and non-symptom factors related to psychiatric disorders and could accommodate both causal/mechanistic and topological explanations.

Reformulating the network theory of mental disorders: Folk psychology as a factor, not a fact

Borsboom et al. (2019) argue that the network theory of mental disorders, if correct, blocks the biological reduction of mental disorders. This is mainly argued through a partial reformulation of network theory which combines multiple realizability of symptoms with a realist interpretation of folk psychological explanations. In this article, I argue that (a) the latter is problematic and that (b) the combination of these arguments voids the previous predictive and explanatory power of network theory. I then present a novel way in which network theory could avoid biological reductionism by considering folk psychology not as a fact, but as a structuring cause of causal connections between intentional state symptoms, together with culture and time period. Drawing from this, a novel principle for network theory is proposed, which allows it to retain force against reductionism while also retaining predictive and explanatory power.