Related Experiment Video
Updated: Jul 10, 2026
08:08
Straightforward Assay for Quantification of Social Avoidance in Drosophila melanogaster
Published on: December 13, 2014
The relationship between avoidant personality disorder and social phobia: a population-based twin study
Ted Reichborn-Kjennerud1, Nikolai Czajkowski, Svenn Torgersen
1Norwegian Institute of Public Health, Box 4404, Nydalen N-0403, Oslo, Norway. ted.reichborn-kjennerud@fhi.no
The American Journal of Psychiatry
|November 3, 2007
Summary
Social phobia and avoidant personality disorder share common genetic factors, but unique environmental influences determine which disorder develops. This suggests a shared genetic vulnerability in women.
Area of Science:
- Psychiatric Genetics
- Clinical Psychology
- Twin Studies
Background:
- Social phobia (SP) and avoidant personality disorder (APD) are frequently comorbid, suggesting shared underlying factors.
- Understanding the etiology of comorbidity is crucial for developing effective prevention and treatment strategies.
Purpose of the Study:
- To investigate the genetic and environmental sources of comorbidity between SP and dimensional APD.
- To estimate the relative contributions of shared and unique genetic and environmental factors to both disorders.
Main Methods:
- A population-based sample of 1,427 female twin pairs from the Norwegian Institute of Public Health Twin Panel was assessed.
- Participants were interviewed using the Structured Interview for DSM-IV Personality and the Composite International Diagnostic Interview.
- Bivariate Cholesky models were employed using the Mx statistical program to analyze genetic and environmental influences.
Main Results:
- The best-fitting model indicated that both additive genetic factors and unique environmental factors influenced SP and APD.
- The same genetic factors were found to influence both avoidant personality disorder and social phobia.
- Environmental factors contributing to each disorder were uncorrelated, suggesting they are unique to each condition.
Conclusions:
- A common genetic vulnerability likely underlies avoidant personality disorder and social phobia in women.
- Environmental risk factors unique to each disorder appear to determine the specific diagnosis in genetically predisposed individuals.
- Findings support the hypothesis of psychobiological dimensions spanning across Axis I and Axis II disorders.
Related Concept Videos
01:26Personality Disorders: Narcissistic and Avoidant
Narcissistic and avoidant personality traits represent two contrasting patterns of behavior that significantly influence social interactions and self-perception. While individuals with narcissistic disorder seek admiration and validation, individuals with avoidant personality disorder withdraw due to fear of judgment.
Characteristics of Narcissistic Personality Disorder
Narcissistic individuals exhibit an inflated sense of self-importance and an excessive need for admiration. They are often...
Characteristics of Narcissistic Personality Disorder
Narcissistic individuals exhibit an inflated sense of self-importance and an excessive need for admiration. They are often...
01:28Social Anxiety Disorder
Social anxiety disorder, also known as social phobia, is characterized by an intense fear of social situations where one might face humiliation, rejection, embarrassment, or negative evaluation. This disorder leads individuals to avoid activities like casual conversations, public speaking, or seemingly simple tasks such as eating, signing documents, or swimming, in public settings. Its impact extends beyond discomfort, often significantly interfering with daily functioning and quality of life.
01:22Personality Disorders: Paranoid and Schizoid
Personality disorders represent enduring cognition, affect, and behavior patterns that significantly deviate from societal norms. These maladaptive traits often lead to difficulties in various domains, including interpersonal relationships, occupational settings, and overall psychological well-being. Paranoid personality disorder and schizoid personality disorder are two distinct conditions marked by odd or eccentric behavior.
Paranoid Personality Disorder
Paranoid personality disorder is...
Paranoid Personality Disorder
Paranoid personality disorder is...
03:34Theory of Romantic Attachment in Adulthood
Attachment is a long-standing connection or bond with others. While Attachment Theory was conceived in developmental psychology to describe infant-caregiver bonding, it's been extended into adulthood to include romantic relationships.
01:09Preparedness and Phobias
Human fear responses to certain stimuli, such as darkness, heights, deep water, and blood, can often arise despite the absence of direct negative experiences. This phenomenon is rooted in evolutionary psychology, which posits that humans have developed a predisposition to fear stimuli that historically posed significant survival threats. This predisposition, known as preparedness, suggests that early humans who developed a fear of potentially dangerous entities, such as venomous snakes and...
01:28Hazan and Shaver's Attachment Styles
Attachment theory, developed initially to explain infant–caregiver bonds, has been extended to illuminate patterns of intimacy in adult romantic relationships. Psychologists Cindy Hazan and Phillip Shaver proposed that the attachment styles observed in infancy form a framework for how individuals approach emotional closeness and conflict in adulthood. These attachment styles—secure, avoidant, and anxious—are linked to enduring patterns of behavior and emotional regulation in adult relationships.