The interpersonal world of psychosis
Authors: Matthew Ratcliffe
Journal: World Psychiatry (2015)

Sass and Byrom 1 do a fine job in explaining the phenomenological approach to delusions, linking themes in phenomenological psychopathology to work on predictive coding, and emphasizing the heterogeneity of delusional experience. Delusions, they maintain, presuppose more enveloping changes in a person's sense of self, body, and world. In this commentary, I will address a theme that is not so prominent in their discussion of these changes but implicit throughout: the interpersonal aspect. In so doing, I seek to complement and elaborate upon their account, as well as point to some avenues for further enquiry. In General Psychopathology, Jaspers offers the following brief remarks about belief-formation and the social world: "Normal convictions are formed in a context of social living and common knowledge… The source for incorrigibility therefore is not to be found in any single phenomenon by itself but in the human situation as a whole, which nobody would surrender lightly. If socially accepted reality totters, people become adrift" 2, p. 104). We can distinguish two complementary themes here. First of all, our belief-formation processes depend upon our relations with other people. For example, I have argued elsewhere that a kind of non-localized trust has a central role to play. For our epistemic practices to be guided by others, those others must be regarded as epistemically competent and also well-meaning. This is not something we ordinarily accept in the form of a debatable proposition. Rather, our default way of experiencing and relating to other people involves, amongst other things, a kind of habitual trust 3. Second, the beliefs that we do form are embedded in a consensus world, in a taken-for-granted background of shared knowledge and practice. Hence belief-formation and belief-content are both shaped by a certain "style" or "form" of interpersonal experience and relatedness. However, this point is not specific to belief. How our surroundings appear to us similarly implicates our relations with specific individuals and with people in general. The phenomenologist and psychiatrist J.H. van den Berg notes how a situation can look quite different, depending on who we are with. We avoid certain people because we want to keep our surroundings "undamaged", while the company of others is pleasant in that "the objects encountered come to no harm" (4, p. 65). In fact, human experience is interpersonally regulated to such an extent that profound and prolonged social deprivation can erode the capacity to distinguish one's body from one's surroundings, imagining from perceiving, and wakefulness from dreaming 5. Pronounced alterations in the overall form of interpersonal experience, in how one encounters and relates to people in general, are thus inextricable from wider-ranging changes in the structure of experience and thought. The point can also be applied to predictive coding models: in addition to exploring how isolated organisms make predictions, detect errors, and compensate for those errors, we ought to consider the roles played by intersubjective regulatory processes. As Sass and Byrom observe, psychosis involves estrangement from the "commonsense" world. Once we emphasize that this world is essentially a public, consensus world, it becomes clearer why there is a change not just in the content of one's beliefs but also in the way in which one believes. Believing that p is the case and that q is not the case involves regarding p but not q as integral to the public world. However, if none of a person's beliefs are rooted in a public world, she cannot make sense of the contrast between p and q in that way. So, when she asserts that something "is the case" or "is not the case", a different kind of conviction must be involved. Global social estrangement could take various different forms. For instance, R.D. Laing famously describes a predicament where others appear only in the guise of existential threat, thus cutting one off from kinds of interpersonal relation that are more usually implicated in the formation, sustenance, and revision of belief 6. But other changes in the structure of intersubjectivity that have the effect of cutting one off from other people in general would similarly impact upon the form of experience and belief. Interpersonal experience in psychosis is therefore potentially quite variable. As well as being inseparable from the structure of delusional experience, interpersonal processes plausibly have an important developmental role to play. It is increasingly acknowledged that there are significant links between trauma and psychosis. In particular, childhood trauma and abuse are claimed to increase vulnerability to psychosis, with some authors maintaining that up to 85% of adults with schizophrenia diagnoses have suffered childhood abuse 7, 8. It is plausible to suggest that early attachment patterns, which nurture a kind of affective trust in others, have an important influence on how one later comes to experience and relate to the interpersonal world as a whole. These patterns can be derailed – to varying degrees – by childhood trauma. Associated epistemic biases in adulthood include an intolerance of ambiguity, inflexible and dogmatic thinking, and a tendency to make judgements based on insufficient information (something that may arise – in part – from a failure to treat others as reliable sources of information) 9. Amongst other things, diminished affective trust would interfere with what Csibra and Gergely call "natural pedagogy", a process whereby ostensive cues from others foster credulity so as to facilitate the transmission of general information about the social world 10. Thus, without a certain way of relating to others, the sense of being rooted in a public world would be compromised from the outset, leading to epistemic dispositions and a more general way of finding oneself in the interpersonal world that could render one susceptible to further unpleasant social experiences and, ultimately, to psychosis. Of course, there may also be very different cases where an endogenous "delusional atmosphere" arises independently of interpersonal relations, with salience dysregulation then driving disruptions of intersubjectivity 7. But, even in this kind of scenario, how others respond could play various roles in determining outcome. Hence, a profound and pervasive estrangement from other people is central to many, perhaps all, variants of delusional experience. It sets one adrift from relations that regulate the form, as well as the content, of experience and belief. Furthermore, altered interpersonal experience is not merely integral to the kinds of experience that Sass and Byrom describe; it has important developmental roles to play too.