Schizotypal personality disorder
|Classification and external resources|
|Cluster A (odd)|
|Cluster B (dramatic)|
|Cluster C (anxious)|
Schizotypal personality disorder is a personality disorder characterized by a need for social isolation, anxiety in social situations, odd behavior and thinking, and often unconventional beliefs. People with this disorder feel extreme discomfort with maintaining close relationships with people, and therefore they often don't. They frequently misinterpret situations as being strange or having unusual meaning for them. Paranormal and superstitious beliefs are not uncommon for these people. People with this disorder seek medical attention for things such as anxiety, depression, or other symptoms.
The American Psychiatric Association defined Schizotypal Personality Disorder as:
A 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 as indicated by 5 or more:
- Ideas of reference (excluding delusions of reference)
- Odd beliefs or magical thinking that influences behavior and is inconsistent with subcultural norms (e.g. superstition, belief in clairvoyance, telepathy, "sixth sense", or bizarre fantasies or preoccupations)
- Unusual perceptual experiences, including bodily illusions
- Odd thinking and speech (e.g. vague, circumstantial, metaphorical, or stereotyped speaking)
- Suspiciousness or paranoid ideation
- Inappropriate or constricted affect
- Behavior or appearance that is odd, eccentric or peculiar
- Lack of close friends or confidants other than first degree relatives
- Excessive social anxiety that does not diminish with familiarity and tends to be associated with paranoid fears rather than negative judgments about self.
The World Health Organization's ICD-10 does not have a diagnosis of schizotypal personality disorder, but (F21) Schizotypal disorder. In ICD-10, Schizotypal disorder is classified as a clinical disorder associated with schizophrenia rather than a personality disorder as with DSM-IV. The DSM-IV designation of schizotypal as a personality disorder is controversial.
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 social withdrawal;
- Odd beliefs or magical thinking, influencing behavior and inconsistent with subcultural norms;
- Suspiciousness 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.
- The disorder runs a chronic course with fluctuations of intensity. Occasionally it evolves into overt schizophrenia. There is no definite onset and its evolution and course are usually those of a personality disorder. It is more common in individuals related to people with schizophrenia and is believed to be part of the genetic "spectrum" of schizophrenia.
 Diagnostic Guidelines
This diagnostic rubric is not recommended for general use because it is not clearly demarcated either from simple schizophrenia or from schizoid or paranoid personality disorders. If the term is used, three or four of the typical features listed above should have been present, continuously or episodically, for at least 2 years. The individual must never have met criteria for schizophrenia itself. A history of schizophrenia in a first-degree relative gives additional weight to the diagnosis but is not a prerequisite.
- Borderline schizophrenia
- Latent schizophrenia
- Latent schizophrenic reactions
- Prepsychotic schizophrenia
- Prodromal schizophrenia
- Pseudoneurotic schizophrenia
- Pseudopsychopathic schizophrenia
- Schizotypal personality disorder
Theodore Millon proposes two subtypes of schizotypal . Any individual with schizotypal personality disorder may exhibit either one of the following somewhat different subtypes (Note that Millon believes it is rare for a personality with one pure variant, but rather a mixture of one major variant with one or more secondary variants):
- insipid schizotypal - a structural exaggeration of the passive-detached pattern. It includes schizoid, depressive, dependent features.
- timorous schizotypal - a structural exaggeration of the active-detached pattern. It includes avoidant, negativistic (passive-aggressive) features.
 Differential diagnosis
There is a high rate of comorbidity with other personality disorders. McGlashan et al. (2000) stated that this may be due to overlapping criteria with other personality disorders, such as avoidant personality disorder, paranoid personality disorder and borderline personality disorder.
There are many similarities between the schizotypal and schizoid personalities. Most notable of the similarities is the inability to initiate or maintain relationships (both friendly and romantic). The difference between the two seems to be that those labeled as schizotypal avoid social interaction because of a deep-seated fear of people. The schizoid individuals simply feel no desire to form relationships, because they see no point in sharing their time with others.
Although listed in the DSM-IV-TR on Axis II, schizotypal personality disorder is widely understood to be a "schizophrenia spectrum" disorder. Rates of schizotypal PD are much higher in relatives of individuals with schizophrenia than in the relatives of people with other mental illnesses or in people without mentally ill relatives. Technically speaking, schizotypal PD may also be considered an "extended phenotype" that helps geneticists track the familial or genetic transmission of the genes that are implicated in schizophrenia.
 Social and environmental
Over time, children learn to interpret social cues and respond appropriately but for people with this disorder, they have a hard time in going past this process successfully so this might lead to irrational beliefs. It's been known that during this process, childhood abuse can alter the brain functioning. 
Schizotypal personality disorder are characterized by a common attentional impairment in varies degrees.  Study suggest that attention deficits could serve as a marker of biological susceptibility to schizotypal personality disorder. The reason is that an individual who has difficulties taking in information may find it difficult in complicated social situations where interpersonal cues and attentive communications are essential for quality interaction. This might eventually cause the invidual withdraw from most social interactions, thus leading to asociality. 
There are dozens of studies showing that individuals with schizotypal PD score similar to individuals with schizophrenia on a very wide range of neuropsychological tests. Cognitive deficits in patients with schizotypal PD are very similar to, but quantitatively milder than, those for patients with schizophrenia.
 Prevalence (epidemiology)
Schizotypal personality disorder occurs in 3% of the general population and occurs slightly more commonly in males.
 See also
- DSM-IV codes (personality disorders)
- ICD-10 codes (personality disorders)
- Paranoid personality disorder
- Schizoid personality disorder
- Schizotypal personality disorder - International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10)
- Millon, Theodore, Personality Disorders in Modern Life, 2004
- Millon, Theodore - Personality Subtypes
- McGlashan, T.H., Grilo, C.M., Skodol, A.E., Gunderson, J.G., Shea, M.T., Morey, L.C., et al. (2000). The collaborative longitudinal personality disorders study: Baseline axis I/II and II/II diagnostic co-occurrence. Acta Psychiatrica Scandinavica, 102, 256-264.
- Fogelson, D.L., Nuechterlein, K.H., Asarnow, R.F., et al., (2007). Avoidant personality disorder is a separable schizophrenia-spectrum personality disorder even when controlling for the presence of paranoid and schizotypal personality disorders: The UCLA family study. Schizophrenia Research, 91, 192-199.
- Deidre M. Anglina, Patricia R. Cohenab, Henian Chena (2008) Duration of early maternal separation and prediction of schizotypal symptoms from early adolescence to midlife, Schizophrenia Research Volume 103, Issue 1, Pages 143-150 (August 2008)
- Howard Berenbaum, Ph.D., Eve M. Valera, Ph.D. and John G. Kerns, Ph.D. (2003) Psychological Trauma and Schizotypal Symptoms, Oxford Journals, Medicine, Schizophrenia Bulletin Volume 29, Number 1 Pp. 143-152
- Mayo Clinic Staff. "Schizotypal personality disorder". Mayo Clinic. http://www.mayoclinic.com/health/schizotypal-personality-disorder/DS00830/DSECTION=causes. Retrieved 21 February 2012.
- Roitman,S.E.L et al. Attentional Functioning in Schizotypal Personality Disorder, 1997
- Matsui, M., Sumiyoshi, T., Kato, K., et al., (2004). Neuropsychological profile in patients with schizotypal personality disorder or schizophrenia. Psychological Reports, 94(2), 387-397.
- Internet Mental Health - schizotypal personality disorder
American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders, fourth edition. Washington, DC: American Psychiatric Association. Retrieved from http://psychcentral.com/disorders/sx33.htm
- ICD-10 diagnostic criteria for Schizotypal Disorder.
- Link collection for resources on Schizotypal Disorder.
- Video lecture by Stanford professor Robert Sapolsky on schizotypal personality and "metamagical thinking".