Schizotypal personality disorder (STPD) is a condition in which people display behaviors that others might consider odd, eccentric, or peculiar. The symptoms may manifest as odd manners of speaking or dressing, strange beliefs, and difficulty forming relationships.

STPD is a personality disorder, meaning that it affects a person’s behavior and their way of thinking. The name relates to the condition being a personality disorder that exists on the schizophrenia spectrum.

In this article, we discuss schizotypal personality disorder in more detail, including the symptoms, diagnosis, and treatment options.

A person with schizotypal personality disorder talking to their therapist.Share on Pinterest
Lucy Lambriex/Getty Images

STPD is a type of personality disorder. This classification means that it affects a person’s behavior and causes them to think, feel, or relate to others in a way that deviates from what society considers normal.

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) groups personality disorders into three broad clusters that it refers to as A, B, and C. STPD is a cluster A personality disorder. According to Mental Health America, these disorders involve behaviors that may seem odd or eccentric to others.

A person with STPD may have peculiar behaviors, odd beliefs, or eccentric speech. They may also experience excessive social anxiety and difficulty forming social connections. Evidence suggests that the prevalence of STPD may vary among different populations and range from 0.6% to 4.6%.

Some people may confuse STPD with schizophrenia, which is a serious mental health condition, or schizoid personality disorder (SPD), which is another cluster A personality disorder. However, although the conditions share similarities, they are different.

The main difference between STPD and schizophrenia is that people with schizophrenia frequently experience characteristic psychotic symptoms, while those with STPD do not. The symptoms of psychosis include losing a sense of reality, which may involve hallucinations and delusions.

STPD and SPD also differ despite both being cluster A personality disorders.

People with STPD are not indifferent to other people and are not completely emotionally detached, but they do present unusual behaviors. Conversely, while people with SPD show a general disinterest and indifference to others and have a complete emotional detachment, they may not display behaviors that people consider unusual.

In addition to sharing symptoms, research also suggests a potential genetic link between all three conditions. For example, evidence indicates that a person is more likely to have one of these conditions if they have a close relative who also has one.

Although most people have their own eccentricities, such behaviors are more noticeable in people displaying signs of STPD. This is particularly true if their patterns of thinking and behaving make relating to others difficult.

Possible symptoms of STPD include:

  • distorted thoughts and perceptions
  • strange or peculiar forms of self-expression
  • anxiety and paranoia in social situations
  • difficulty forming close relationships
  • magical thinking, such as believing in superstitions or telepathy

Evidence suggests that genetic, social, and environmental factors play a role in the development of STPD, although more research is necessary to confirm this.

The apparent genetic link means that a person has a higher risk of developing STPD if they have a relative with either STPD, schizophrenia, or another personality disorder.

In addition to a genetic susceptibility, certain experiences — such as abuse, neglect, trauma, stress, and emotionally detached caregivers — likely influence a person’s chance of developing STPD.

A doctor will only diagnose STPD if a person meets five of the nine criteria that the DSM-5 sets out. These criteria are:

  • ideas of reference, which are false beliefs that random events directly relate to a person
  • odd beliefs or magical thinking
  • unusual perceptual experiences and bodily illusions
  • odd thinking and speech
  • suspiciousness or paranoid ideation
  • inappropriate reactions or a lack of expressive range and emotional intensity
  • behavior or appearance that others likely see as odd, eccentric, or peculiar
  • lack of close friends
  • constant and excessive social anxiety that may relate to paranoid fears

Alternatively, the International Classification of Diseases (ICD-11) has a separate set of criteria, which include a pattern of unusual speech and perceptions, beliefs, and behaviors that are not sufficient to meet the diagnostic requirements of schizophrenia.

If a person receives a diagnosis of STPD, a doctor will likely suggest a combination of medications and therapy.

Although there is no medication to treat STPD specifically, research suggests that second-generation antipsychotics, which help treat schizophrenia, may be effective in managing symptoms of STPD.

In particular, medications such as risperidone and olanzapine have shown benefits for treating STPD. Depending on a person’s other symptoms or comorbid conditions, a doctor may also prescribe antidepressants or other neuroactive drugs.

Many types of therapy may also be beneficial. For example, psychotherapy, or talking therapy, may help people learn how to manage their symptoms and form or maintain relationships. Learning these strategies in combination with social skills training may help people learn how to respond to social cues and feel more comfortable in social situations.

Cognitive behavioral therapy (CBT) may help people address certain behaviors, learn how to recognize unusual or harmful thoughts, and understand how to change them. For some people, family therapy may also be useful to strengthen relationships with family members and provide a feeling of support.

Evidence suggests that people with STPD have an increased risk of:

  • depression
  • anxiety
  • educational and occupational problems
  • social difficulties
  • drug and alcohol use disorders
  • suicidal ideation
  • psychotic episodes
  • additional personality disorders

STPD is a cluster A personality disorder, which means that people with the condition find it difficult to relate to others. In particular, people with STPD display behaviors that society may consider to be odd or eccentric. It exists within the schizophrenia spectrum but differs from other conditions in the spectrum, such as schizophrenia and SPD.

Genetic, social, and environmental factors likely play a role in its development. People will only receive a diagnosis if they display certain behaviors, such as magical thinking, paranoia, and inappropriate emotional reactions.

The current treatments usually involve a combination of medications and therapy. People with STPD are also more likely than people without the condition to have depression, addictive behaviors, and other personality disorders.