Subthreshold psychotic experiences are widely reported within otherwise healthy populations. Their phenomenology is broad and very heterogeneous ranging from meaningful coincidences and precognitive dreams over haunting to out-of-body experiences and visual as well as auditory hallucinations.
Although creative aspects of these experiences are implied too, a similarity in form and content to positive symptoms in schizophrenia (e.g., delusion, disordered thought, and hallucinations) or schizotypy (e.g. magical thinking, unusual perceptual experiences, ideas of reference or paranoid ideation) seems to be obvious. However, the borderline between normal and pathological experiences and behaviour is unclear.
The so called “continuum approach” assumes that schizophrenia or schizotypy are not discrete or categorical illness entities. It implies a gradient in the severity of the symptoms, ranging from healthy population to full-blown schizophrenia. As such, psychotic signs are no longer restricted to formal diagnoses according to DSM or ICD, but would, instead, complete the spectrum of psychological and biological features that characterize individual variations among human beings.
Can subthreshold psychotic experiences be integrated in this continuum? Do individuals indicating such experiences lack some social cognitive abilities and are particularly vulnerable to false inferences in their social world. How are these experiences related to increased neural activity or an abnormal dopaminergic neurotransmission?
These and similar questions will be discussed in the presentation.
Disclosure of interest
The author has not supplied his declaration of competing interest.