In DSM-IV, the schizotypal personality is grouped under borderline conditions with borderline personality disorder.
- pervasive pattern of social and interpersonal deficits marked by acute discomfort with, and reduced capacity for, close relationships as well as by cognitive or perceptual distortions and eccentricities of behavior, beginning by early adulthood and present in a variety of contexts
In ICD-10, Schizotypal disorder is classified as a clinical disorder associated with schizophrenia rather than a personality disorder as with DSM-IV. The ICD definition is:
A disorder characterized by eccentric behavior and anomalies of thinking and affect which resemble those seen in schizophrenia, though no definite and characteristic schizophrenic anomalies have occurred at any stage. There is no dominant or typical disturbance, but any of the following may be present:
- inappropriate or constricted affect (the individual appears cold and aloof); Behavior or appearance that is odd, eccentric or peculiar;
- poor rapport with others and a tendency to withdraw socially;
- odd beliefs or magical thinking, influencing behavior and inconsistent with subcultural norms;
- duspiciousness or paranoid ideas;
- obsessive ruminations without inner resistance, often with dysmorphophobic, sexual or aggressive contents;
- unusual perceptual experiences including somatosensory (bodily) or other illusions, depersonalization or derealization;
- vague, circumstantial, metaphorical, over-elaborate or stereotyped thinking, manifested by odd speech or in other ways, without gross incoherence;
- occasional transient quasi-psychotic episodes with intense illusions, auditory or other hallucinations and delusion-like ideas, usually occurring without external provocation.
It has been shown that schizotypal personality disorder has a genetic link with chronic schizophrenia
- more common in individuals related to people with schizophrenia