Self‐Disorders as schizophrenia spectrum vulnerability phenotypes

Schizophrenia spectrum disorders are characterised by manifold psychopathological expressions,
which might include major symptoms (such as delusions, hallucinations or social withdrawal),
psychobehavioural enduring personality patterns (e.g. schizoid/schizotypal traits), or more subtle,
quasi‐ineffable changes in the structure of subjective experience. A cluster of such anomalous
subjective experiences, namely basic anomalies of self‐awareness (Self‐Disorders, SDs), were
emphasized in classic literature and in phenomenological psychiatry as an essential clinical feature
of schizophrenia, anchoring the coherence of its symptoms as well as of its spectrum
manifestations.
However, the potential topicality of SDs for the delineation of phenotypic vulnerability traits, as
well as for the construct validity of the concept of schizophrenia spectrum has remained relatively
neglected.
The current research project was undertaken to validate the status of SDs as basic subjective trait
phenotypes of Schizophrenia Spectrum and explore the translational value of a newly developed,
ad hoc assessment instrument for the clinical charting of SDs (Examination of Anomalous Self‐
Experience, EASE).
First we tested the assumption of SDs as a discriminant psychopathological feature of the
schizophrenia spectrum – as emerged from previous studies in clinical populations – in a
genetically high‐risk, non‐help‐seeking sample previously assessed in the Copenhagen
Schizophrenia Linkage Study (1989‐1999).
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Second we tested SDs discriminative capacity with respect to non‐psychotic configurations of the
Schizophrenia Spectrum, adopting Meehl’s schizotaxia‐schizotypy heuristic model (i.e. a diathesic
model suitable to capture psychobehavioural phenotypic expressions of vulnerability below the
threshold of clinically diagnosable conditions).
Third, we addressed one of the major limitations for the translational implementation of these