Abstract
Phenomenological approaches to subjective experience are becoming increasingly important to psychiatry, particularly as a way to integrate patients’ self-descriptions (i.e. first person data) with behavioural descriptive psychopathology (i.e. third-person, observational data). In this vein, Kim et al. [1], found an association between positive symptoms and anomalous subjective experiences in a sample of outpatients with schizophrenia. The results, which extend transculturally the already vast amount of empirical evidence supporting Huber's Basic Symptoms (BS) Model, are worth further comments.
Indeed, the notion of basic symptoms (BS) is currently gaining international recognition primarily for the purpose of individual risk assessment of impending psychosis. Specifically, a subset of BS, mostly indicative of self-perceived loss of cognitive proficiency (e.g. thought interference, thought perseveration, thought pressure, disturbances of receptive language), has been proposed as subsidiary to the Personal Assessment and Crisis Evaluation (PACE) ultra-high risk criteria to further ‘close-in’ subjects at imminent risk of developing psychosis [2].
However, the operational emphasis on some at-risk BS for the purpose of optimizing targeted early interventions [3] does not exhaust the clinical translational potential of the BS model.
Briefly, BS are pervasive alterations of subjective experience, appearing at different phases of schizophrenia (i.e. prodrome, onset and post-psychotic states) and were conceptualized as the first experientially accessible manifestation of the neurobiological dysfunction underlying schizophrenia. By documenting the ubiquity of such non-psychotic distortions of subjective experience across the syndromic course of schizophrenia, Huber and colleagues prompted a richer phenomenological description of schizophrenic psychopathology. Concretely, the BS model offers a clinical entry point to enrich the psychological understanding of major symptoms dimensions of schizophrenia (including positive, negative and depressive symptoms) in their longitudinal unfolding.
According to the BS model full-blown psychotic symptoms (such as Schneiderian first rank symptoms) are psychopathological end-products aligned along an experiential continuum with BS. Transitions along such a continuum occur through four clinically recognizable phases: I basal irritation (increasingly disturbing, unspecific BS); II intermediate phenomena (i.e. progressively more characteristic BS, such as depersonalization-derealization, and overwhelming impressions of self-reference); III psychotic externalization (i.e. initial, vague impressions of an external, influencing causality); and IV content concretization (i.e. fully formed psychotic narratives, with articulated causal explanations). The intrinsically developmental character of such experiential transformation might account for the only moderate magnitude of cross-sectional correlations between BS (which dominate phases I and II) and positive symptoms (which occur in phases III and IV and could partly attenuate the cognitive-affective distress related to BS) [1,4].
Besides positive symptoms, the profound distortions of subjective experience that BS attest might also exacerbate other symptom dimensions. The following quotes exemplify such potential, clinically meaningful connections:
[an] enduring and pervasive feeling of being unreal…When I realized this condition was permanent, to perceive myself as in a movie, I understood it would eventually destroy the core of my life. [5]
I tried sitting in my apartment and reading; the words looked perfectly familiar…but…I read one paragraph ten times, could make no sense of it…I tried listening to the radio but the sounds went through my head like a buzz saw…I decided, finally, to spend my days sitting in the park watching the birds on the lake. [6]
Both the quotes relate anomalous subjective experiences (i.e. depersonalization-derealization and disturbance of receptive language) to rather understandable affective and psycho-behavioural reactions (i.e. demoralization/depressive retrospection and de-socializing behavioural isolation). Notably, these associations have also been confirmed in quantitative studies adopting the Bonn Scale for the Assessment of Basic Symptoms (BSABS) [7,8].
In my view, this constitutes a fundamental, yet largely unthematized, translational feature of Huber's BS model: it prompts clinical instruments for a more articulated, patient-centred understanding of schizophrenic psychopathology beyond the crust of major diagnostic symptoms.