Schizoid Personality Disorder Fast Facts

Schizoid personality disorder (ScPD) is a mental condition in which a person has little or no interest in interaction or relationships with other people.

ScPD affects up to 5% of people in the United States, making it a common personality disorder.

ScPD appears to affect men slightly more often than women.

People who have relatives with schizophrenia or schizotypal personality disorder are at an increased risk for ScPD.

Personality disorders like ScPD are characterized by long-term patterns of behavior that remain consistent over time.

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ScPD affects up to 5% of people in the United States, making it a common personality disorder.

What is Schizoid Personality Disorder?

Schizoid personality disorder (ScPD) is an illness characterized by a lack of interest in interacting with other people. People with ScPD prefer to be alone and typically are uninterested in developing close relationships with other people. In addition, they may be socially awkward when they do interact, and they may not exhibit a typical range of emotional expression.

ScPD is one of a group of conditions called Cluster A personality disorders. This group also includes paranoid personality disorder and schizotypal personality disorder.

Symptoms of Schizoid Personality Disorder

Common symptoms of ScPD include:

  • Strong preference for spending time and doing activities alone
  • No desire for or enjoyment from close relationships, even with family
  • No close friends
  • Lack of enjoyment of most activities
  • Flat emotional affect
  • Indifference to approval or criticism from others
  • Little or no interest in sex with another person

Difference from Schizotypal Personality Disorder and Schizophrenia

Schizoid personality disorder has some characteristics in common with both schizotypal personality disorder and schizophrenia. For example, people with all three conditions may have trouble interacting socially, and others often see their behavior as odd. However, there are some critical differences between ScPD and the other two conditions, including:

  • People with ScPD aren’t disconnected from reality and typically don’t experience hallucinations, delusions, or paranoia.
  • People with ScPD can interact rationally and coherently, even if their interaction is unusual.

What Causes Schizoid Personality Disorder?

The exact cause of ScPD has not been discovered. However, several factors seem to put an individual at increased risk of ScPD.

  • Family history and genetics. People with ScPD often have a family history of schizophrenia or schizotypal personality disorder. Therefore, scientists suspect a connection between these disorders and a possible genetic component to ScPD, but no definite association with any gene or group of genes has been discovered.
  • Childhood experiences. Some researchers believe that a child who has experienced neglect or emotional detachment from their parents is at increased risk of ScPD.

Is Schizoid Personality Disorder Hereditary?

Scientists have not yet been able to identify a specific genetic component that increases the risk of ScPD. Inherited genes may increase an individual’s susceptibility to ScPD, but the disorder’s actual development may result from external triggering circumstances.

How Is Schizoid Personality Disorder Detected?

ScPD typically is not diagnosed before early adulthood, but some symptoms may appear in childhood. Early symptoms can include:

  • Emotional coldness
  • Strong desire to be alone
  • Lack of interest in friends
  • Lack of reaction to praise or criticism
  • Trouble in school

How Is Schizoid Personality Disorder Diagnosed?

Diagnosis of ScPD begins with determining that the patient has a cluster of symptoms that meet the diagnostic criteria for the disorder. A doctor will start with a physical exam to rule out biological problems that may be causing symptoms. After these exams, if the doctor suspects that ScD or another mental disorder is the cause of the symptoms, they may recommend a psychological or psychiatric assessment to solidify the diagnosis further.

Diagnostic steps may include:

  • A physical exam. This exam rules out physical conditions that could be causing the symptoms.
  • Psychological assessments. These assessments may take the form of questionnaires or talk sessions with a mental health professional to assess the patient’s mood, mental state, and mental health history. Family members or caregivers may also be asked to participate in these assessments.

The results of the psychological assessments will be compared to the diagnostic criteria for ScPD in the Diagnostic and Statistical Manual of Mental Disorders (DSM). The DSM criteria for ScPD include:

  • Disinterest in relationships.
  • Lack of emotional expression when interacting with others.
  • At least four symptoms are present.
  • The symptoms begin by early adulthood.


How Is Schizoid Personality Disorder Treated?

There is no cure for ScPD, and no medications are commonly used to treat the disorder. However, psychotherapy may be helpful, and some medicines may be used to treat symptoms of other co-existing disorders.


People with ScPD are unlikely to seek treatment on their own. Their lack of interest in social relationships and concern about what others think often make them unmotivated to change their behavior. However, if they do enter treatment and stick to a treatment plan, some improvement in symptoms is possible.

The most commonly used therapeutic approach is cognitive-behavioral therapy (CBT). This type of treatment focuses on teaching the patient to recognize inaccurate perceptions about themselves and others and develop strategies for dealing with these misperceptions when they occur.


In some cases, medications may help control co-existing problems such as anxiety or depression. The drugs used to treat these symptoms include selective serotonin reuptake inhibitors (SSRIs) and anti-anxiety medications.

How Does Schizoid Personality Disorder Progress?

People with ScPD have trouble forming and maintaining relationships, and their eccentric social behavior may prevent them from functioning normally. Many people with the disorder can perform reasonably well at work, especially if they can work alone. However, they are unlikely to seek treatment, and their behavior may have increasingly severe consequences over time.

Long-term adverse effects of ScPD can include:

  • Unemployment or homelessness
  • Financial difficulties
  • Legal difficulties
  • Social isolation
  • Lack of healthy interpersonal relationships

How Is Schizoid Personality Disorder Prevented?

There is no known way to prevent ScPD, but early intervention may help someone with the disorder learn to form more healthy relationships with other people.

Schizoid Personality Disorder Caregiver Tips

Many people with schizoid personality disorder also suffer from other brain and mental health-related issues, a condition called co-morbidity. Here are a few of the disorders commonly associated with ScPD:

Schizoid Personality Disorder Brain Science

Schizoid personality disorder is one of the least studied personality disorders, possibly because people with the condition rarely seek treatment, causing the disorder to go often undiagnosed. Some studies have found possible genetic associations with ScPD, but the research is inconclusive. Much of the research that involves ScPD focuses on the disorder’s schizoid traits and their potential link to schizotypal personality disorder and schizophrenia.

Schizoid Personality Disorder Research

Title: Psychopathological Differences Between Asperger Syndrome and Schizotypal Disorder in an Adult Sample

Stage: Completed

Study chair: Sidse Arnfred, MD

Mental Health Services in the Capital Region

Copenhagen, Denmark 

The purpose of this study is to identify psychopathology (psychiatric symptoms) that can differentiate between Schizotypal Disorder (SD) and Asperger Syndrome (normal IQ, no language impairment Autism Spectrum Disorder) (AS) in young adults.

With our present knowledge, the differentiation between AS and SD can be difficult. They both present with social difficulties, odd (but not psychotic) behavior, and a ‘feeling of not being as everyone else.’ Studies suggest that adults with AS symptoms are either overlooked or diagnosed within the schizophrenia spectrum in Adult Psychiatry.

A ‘correct’ diagnosis is essential, as it is the first step towards the most optimal plan, treatment, and rehabilitation for the patient. The only way to diagnose psychiatric illness is the description of present psychopathology.

To identify symptoms that can differentiate between the two disorders, we will use semi-structured interviews to explore present psychopathology in young adults with typical symptoms of SD and AS, respectively, with a special focus on the presence of alterations in self-experience. Alterations in self-experience are typical for the schizophrenia spectrum and are therefore not thought to be equally present in AS and SD.

The hypotheses are that the total level of altered experiences is higher in SD than in AS and with a different pattern of altered experiences in SD than in AS. If the hypotheses are true, examining altered self-experience will be valuable to aid clinical differentiation between the two disorders.

Title: Brain Imaging in Early Psychosis

Stage: Enrolling by invitation

Washington University School of Medicine

Saint Louis, MO 

Schizophrenia is a devastating illness inflicting about 1% of the population worldwide. Symptoms of schizophrenia include paranoia, hallucinations, and disorganized behaviors and are associated with lifelong occupational and social disability. It typically develops in adolescence or early adulthood, particularly formative periods when significant educational, vocational, and social life changes occur. Then, the brain undergoes a rearrangement of critical neural circuits. The “prodrome” is the period before the onset of a psychotic disorder, like schizophrenia. Prodromal youth often have significant emotional distress and social withdrawal, and family members may observe a concerning change in behavior or school or work performance. Identifying those at clinical high risk for a psychotic disorder is important, as early intervention can improve symptoms and functioning and could prevent the eventual development of a psychotic disorder. This study will focus on individuals aged 13-25 years who have met the criteria for a psychosis-risk syndrome (or attenuated psychosis syndrome) or are at a very early stage (first three years after diagnosis) of a psychotic disorder, such as schizophrenia or schizoaffective disorder. Involvement will be either 2 or 3 partial days at Washington University and will involve approximately 3 hours of MRI scanning and up to 6 hours of behavioral testing. Additionally, the investigators will study the effect of genetics on the patterns of brain connectivity in various psychiatric populations. DNA will be collected non-invasively from saliva and stored and processed in Washington University facilities.


Title: Compassion and Metacognition in Schizotypal Personality (CMBT)

Stage: Recruiting

Principal Investigator: Simone Cheli

Tages Onlus

Florence, Italy 

The purpose of this study is to assess the safety and efficacy of a newly developed psychotherapy for schizotypal personality disorder. This new form of psychotherapy integrates compassion-focused therapy and metacognitively oriented psychotherapy.

After being informed about the study and potential risks, all patients giving written informed consent will undergo a psychological assessment to determine eligibility for study entry. Patients who meet the eligibility requirements will be randomized, in a double-blind manner, in a 1:1 ratio to new integrative psychotherapy or treatment as usual (cognitive behavioral therapy plus standard psychopharmacological treatment). One month after the conclusion of the two forms of treatment (both lasting six months), patients will have access to the final follow-up assessment.

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