Schizotypal Personality Disorder (STPD) Symptoms and Causes

Schizotypal Personality Disorder

Schizotypal Personality Disorder (SPD), also known as schizotypal disorder, stands out within the schizophrenia spectrum disorders as characterized by peculiar patterns of thinking and behavior. Individuals diagnosed with SPD often exhibit odd or eccentric mannerisms that can significantly impact their daily functioning and interpersonal relationships.

The disorder is specifically described in the Diagnostic and Statistical Manual of Mental Disorders (DSM) classification as a personality disorder, characterized by thought disorder, paranoia, a unique type of social anxiety, derealization, transient psychosis, and unconventional beliefs. It is distinct from Schizoid personality disorder, or Schizoaffective disorder.

People with this personality disorder typically experience distorted thinking, which may manifest as an obsession with superstitions or paranormal phenomena. They may have unusual speech patterns or react inappropriately to social cues, making interaction challenging.

These behaviors and experiences align with the broader spectrum of schizophrenia-related disorders, where SPD is less severe but still impacts the individual’s life.

The prevalence of schizotypal personality disorder in the United States is estimated to be around 3% of the general population, with somewhat higher rates among men (4.2%) than women (3.7%). The disorder is seen globally, with occurrence rates varying based on geographical and cultural factors that may influence both the expression of symptoms and the willingness to seek treatment.

SPD is typically diagnosed in late adolescence or early adulthood, with a slight male predominance noted in clinical settings. However, these statistics are subject to change as diagnostic practices evolve and awareness increases.

Causes and Risk Factors

People who have relatives with schizotypy, mood disorders, or other schizophrenia-related diseases are more likely to acquire StPD. Environmental variables are thought to have a major influence in the disorder’s emergence. The COMT Val158Met polymorphism and its Val or Met allele are thought to be linked to schizotypal personality disorder. This is because these genes influence synthesis of dopamine (a neurochemical thought to be associated with schizotypal traits) in the brain.

The gene may potentially lead to a loss in gray matter in the prefrontal cortex. This may result in decreased speech, decision-making abilities, cognitive flexibility, and changed perceptual experiences.

Another gene, NOTCH4, is suspected to be linked to schizophrenia spectrum diseases. It can cause disturbances in the occipital cortex, resulting in schizotypic symptoms. The GLRA1 and p250GAP genes may also be related with StPD. They may cause abnormally low amounts of glutamic acids in the NDMA receptors, impairing memory and learning.

Environmental Factors

The environment in which an individual is raised can significantly impact the development of schizotypal traits. Exposure to trauma, abuse, or neglect during critical developmental periods may increase susceptibility to SPD.

Evidence suggests that parenting styles, early separation, childhood trauma, and childhood neglect can all contribute to the development of schizotypal traits. There is also evidence that disruptions in brain development during the prenatal period could influence the development of StPD.

Children learn to comprehend social cues and behave appropriately over time, but for unexplained reasons, people with this disease do not benefit from this process. People with schizotypal personality disorder may have observed little emotional expressiveness from their parents while growing up.

Another hypothesis is that they were unduly criticized or felt like they were continuously under threat, potentially resulting in the start of social anxiety, unusual thinking patterns, and dulled affect seen in StPD.

Symptoms of Schizotypal Personality Disorder

Diagnosis of StPD relies on the criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). A person must exhibit a combination of behavioral and cognitive symptoms that are not attributable to another condition. To be diagnosed, they must meet criteria that include significant discomfort in close relationships, cognitive or perceptual distortions, and eccentricities in behavior.

At least five out of the following specific symptoms listed in the DSM-5 must be present. These are:

  • odd/magical beliefs
  • Ideas of reference (but not delusions of reference)
  • social anxiety
  • not having close friends
  • odd or eccentric behavior
  • odd speech
  • unusual perceptions
  • suspiciousness
  • schizo-obsessive behaviors
  • constricted affect


Patients with StPD may have difficulty detecting their own or others’ emotions. This can lead to difficulty expressing emotions. They may have limited reactions to other people’s emotions and be ambivalent.

People with StPD frequently have abnormal facial expressions, as well as abnormal eye movements and problems responding to stimuli. They are more prone to substance misuse and suicidal thoughts.

Magical Ideation

People with StPD frequently exhibit unusual and magical thinking. They are more prone to believe in supernatural events and entities.

They may also believe that others are more competent and have deep-seated and pervasive insecurities. Strange thought processes could be a defensive technique against these emotions. Individuals with StPD typically have low degrees of self-awareness. They may imagine that others perceive them more adversely than they do.

People with StPD frequently experience significant social anxiety and paranoid ideation. People with StPD frequently have delusions of reference. They may feel as if expressing oneself is unsafe.

Mental Health Comorbidities

Individuals with Schizotypal Personality Disorder frequently experience additional mental health conditions that compound their challenges. The following are among the comobidities:

Treatment Options

When addressing schizotypal personality disorder, treatment typically encompasses a combination of therapies and medications tailored to the individual’s specific needs. These interventions aim to manage symptoms and improve social and occupational functioning.

Medication is not the primary treatment for SPD but can be instrumental when prescribed correctly. Antidepressants might be used to alleviate associated symptoms, such as depression or anxiety. In certain cases, antipsychotic medications can be effective, especially if the person experiences more severe symptoms like perceptual distortions or odd beliefs. However, the prescription of antipsychotics must be approached cautiously, considering potential side effects and the patient’s overall health.

According to Theodore Millon, schizotypal personality disorder is one of the easiest to recognize but one of the most difficult to treat with psychotherapy. Cognitive remediation therapy, metacognitive therapy, supportive psychotherapy, social skills training, and cognitive-behavioral therapy may all be useful treatments for the illness.

Increased social connection with others may assist in reducing symptoms of StPD. Support is especially necessary for schizotypal individuals who exhibit predominant paranoid symptoms, as they may struggle even in highly structured groups.

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Last Updated on April 5, 2024