Personality Pathway: How Traits Shape Social Anxiety and Its Treatment

Social anxiety disorder is one of the most common and most disabling of the anxiety conditions, marked by an intense and persistent fear of being judged, embarrassed or rejected by others. For decades, clinicians have known that people with social anxiety are more likely than the general population to show disordered personality patterns, especially avoidant personality disorder. What has remained far less clear is how the broader architecture of personality pathology — not just categorical diagnoses, but the continuous dimensions of self-functioning, interpersonal functioning and maladaptive traits — relates to the severity of social anxiety and to how patients respond when they finally receive treatment. A new study from researchers at the University of New South Wales and the Black Dog Institute in Sydney, published in BMC Psychology, offers one of the first direct looks at this question in the context of a modern, compressed form of digital therapy.

The research, led by Kayla R. Steele and Jill M. Newby, examined fifty-nine adults whose primary diagnosis was social anxiety disorder. All of them completed an intensive form of internet-delivered cognitive behavioural therapy, or iCBT — a treatment format that condenses the principles of face-to-face CBT into a structured online program delivered over a shorter, more concentrated period rather than spread across many weeks. Intensive iCBT has become an increasingly important tool in mental health systems trying to close the gap between demand and available therapists, and trials of this format have generally shown that rapid symptom improvement is achievable without a clinician in the room. The Sydney team wanted to know whether a patient’s personality profile would influence not only how sick they were at the start, but how much they improved.

To answer that, the researchers turned to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, and specifically its Alternative Model for Personality Disorders, known as the AMPD. Rather than asking whether a patient meets a rigid checklist for a personality disorder, the AMPD describes personality pathology along two axes. The first is level of personality functioning, which captures how well a person maintains a coherent sense of self, regulates emotions and pursues meaningful goals, and how effectively they form intimate relationships, empathise with others and navigate social groups. The second is a set of maladaptive trait domains — negative affectivity, detachment, antagonism, disinhibition and psychoticism — that represent extreme, inflexible and harmful versions of normal personality dimensions. Standard questionnaires exist for both axes: the LPFS-BF for functioning and the PID-5-BF for traits, and both were administered at the start of treatment and again at its end.

Alongside these personality measures, participants completed well-validated scales for social anxiety — the Social Interaction Anxiety Scale and the Social Phobia Scale — as well as the Patient Health Questionnaire for depressive symptoms and the Work and Social Adjustment Scale for psychosocial impairment. Diagnostic interviews using the Anxiety and Disorders Interview Schedule for DSM-5 established the presence of social anxiety disorder and any comorbid major depressive disorder. This dual assessment structure meant the researchers could map the full landscape of personality pathology onto the symptom burden of each patient, and then track how that landscape changed as the therapy did its work.

The baseline findings were nuanced. On average, the group showed only mild impairments in personality functioning, and their maladaptive trait scores were largely in the non-clinical range — a striking result given that social anxiety disorder has historically been tightly linked with personality disorder diagnoses. However, the picture darkened considerably for participants who also carried a diagnosis of major depressive disorder. Comorbidity with depression was associated with greater impairment in personality functioning, echoing a large body of literature showing that depression tends to erode self-esteem, self-direction and interpersonal trust in ways that overlap with personality pathology.

Crucially, even within a sample that was not, on the whole, severely personality-disordered, the dimensional measures mattered. Greater impairment in personality functioning — particularly in the self-domain, which covers identity, self-worth and emotional regulation — was associated with more severe social anxiety symptoms. So too were higher levels of maladaptive traits, including negative affectivity, the tendency to experience frequent and intense negative emotions; disinhibition, reflecting impulsivity and difficulty with planning and restraint; and even psychoticism, the trait domain covering unusual thoughts and perceptual experiences. That such a broad sweep of trait pathology correlated with social anxiety severity suggests that the disorder does not simply ride on shyness or avoidance, but is embedded in a wider matrix of personality vulnerability that clinicians rarely measure in routine anxiety care.

The treatment findings, however, complicate the intuitive story that sicker personalities should mean poorer recovery. After the researchers statistically controlled for baseline symptom severity, personality pathology — both impaired functioning and maladaptive traits — no longer significantly predicted post-treatment levels of social anxiety, depressive symptoms or psychosocial impairment. In other words, once you know how severe a patient’s symptoms were before therapy, knowing their personality profile adds little independent information about how they will fare in the short term. This is an important message for an era in which personality pathology is sometimes treated as a contraindication for streamlined psychological treatments. The data here suggest that patients with social anxiety and mild-to-moderate personality difficulties should not be excluded from intensive iCBT on the assumption that their personalities will block progress.

Perhaps the most provocative result concerned change in the personality measures themselves. After the intensive program, participants showed significant reductions in both personality functioning impairment and maladaptive trait severity. Symptoms and personality moved together — which raises a deep theoretical question about causality and stability. The authors are appropriately cautious here, noting that these reductions may not be indicative of enduring personality change. Traits are conventionally understood as stable dispositions, and short-term improvements measured by questionnaires may simply reflect the lifting of anxious and depressive states that had temporarily inflated pathological responding. Distinguishing genuine trait change from state-dependent fluctuation would require longer follow-up, and this study did not establish that.

For the AMPD’s champions, the findings still count as a validation of sorts. The study demonstrated that the model’s dimensional components are clinically relevant in social anxiety disorder: they discriminate between more and less severe presentations, they flag comorbid depression, and they shift in parallel with treatment response. That a personality framework built for the personality disorders section of the DSM can illuminate a common anxiety condition supports the broader argument that personality pathology is better understood as a continuum woven through all mental disorders rather than a separate diagnostic silo. It also gives clinicians a practical vocabulary — self-functioning, negative affectivity, disinhibition — for describing the patients who struggle most, even when those patients fall short of a personality disorder diagnosis.

The study’s limitations are worth keeping in view. Fifty-nine participants is a modest sample, the trial was registered with the Australian New Zealand Clinical Trials Registry in March 2022, and the analysis lacked the long-term follow-up needed to say anything about durability. The authors themselves frame the results as preliminary. Yet the implications are concrete: personality assessment could help identify social anxiety patients who present with heavier symptom burdens, while reassuring clinicians that such pathology need not derail short-term digital treatment. As iCBT programs scale up worldwide, this kind of research helps answer the question that matters most in practice — not just who has the disorder, but who will get better, and why.

Subject of Research: Dimensional personality functioning and maladaptive traits in social anxiety disorder and their association with symptom severity and treatment response to intensive iCBT

Article Title: Personality functioning and maladaptive traits in social anxiety disorder: associations with symptom severity and change following intensive iCBT

Article References: Steele, K. R., & Newby, J. M. (2026). Personality functioning and maladaptive traits in social anxiety disorder: associations with symptom severity and change following intensive iCBT. BMC Psychology. https://doi.org/10.1186/s40359-026-05515-0

Image Credits: AI Generated

DOI: 10.1186/s40359-026-05515-0

Keywords: social anxiety disorder, personality functioning, maladaptive traits, AMPD, iCBT, DSM-5, cognitive behavioural therapy, negative affectivity, disinhibition, comorbid depression, digital mental health, BMC Psychology