Anxiety and Its Disorders: The Nature and Treatment of Anxiety and Panic

Barlow's central claim is that anxiety disorders are best understood through a triple vulnerability framework: a generalized biological vulnerability (heritable temperament), a generalized psychological vulnerability stemming from early experiences that shape a sense of control, and a specific psychological vulnerability that focuses anxiety on particular stimuli or situations. This rejects purely descriptive DSM-based accounts that catalog symptoms without explaining etiology. It also rejects single-cause models—whether strictly biological or strictly learning-based—by insisting that disordered anxiety requires the convergence of all three vulnerability levels. The 2002 second edition reframed this argument explicitly within emotion theory, positioning anxiety and panic as dysregulated variants of normal emotional processes rather than categorically distinct pathologies.

The book introduced and elaborated the "triple vulnerability" model of anxiety disorders. The three components are: (1) generalized biological vulnerability, often operationalized as neuroticism or heritable temperament; (2) generalized psychological vulnerability, based on early learning experiences that foster a diminished sense of control over salient life events; and (3) specific psychological vulnerability, acquired through learning experiences that focus anxiety on particular objects, situations, or bodily sensations. The model is used today as an organizing heuristic in anxiety-disorder research, including studies examining whether specific vulnerabilities (such as thought-action fusion for OCD or intolerance of uncertainty for GAD) incrementally predict particular disorder constructs beyond general temperament . It also structures the Oxford Handbook chapter on understanding anxiety disorders .

The 2002 second edition is not a revision but a substantially new book. A contemporary review in the American Journal of Psychiatry described it as "an entirely new book" rather than an update . The first edition (1988, Guilford Press) was a single-authored 698-page volume. The second edition divides into two parts: eight chapters presenting Barlow's theoretical account of fear, panic, and anxiety within emotion theory, and seven chapters on specific disorders, most co-authored with Boston University colleagues . The second edition also explicitly frames the triple vulnerability model—a formulation Barlow had crystallized in a 2000 American Psychologist article—as the book's theoretical spine .

Support is mixed and dimension-dependent. A large study of 700 outpatients at Boston University's Center for Anxiety and Related Disorders found that general biological vulnerabilities (neuroticism, low extraversion) were the strongest and most consistent predictors across anxiety and mood disorder constructs. General psychological vulnerability (perceived control) predicted generalized anxiety disorder and OCD specifically. However, of the disorder-specific vulnerabilities tested, only thought-action fusion for OCD performed as theorized; intolerance of uncertainty for GAD and dysfunctional attitudes for depression did not show the predicted specific associations . This suggests the model's general architecture is useful, but its specific-vulnerability components require further refinement and disorder-specific validation.

Earlier conditioning models treated anxiety disorders as products of simple associative learning—a traumatic event paired with a stimulus produces a phobia. Barlow's triple vulnerability model absorbs learning but embeds it within a broader diathesis-stress architecture. Conditioning alone is insufficient: the same traumatic event does not produce an anxiety disorder in everyone. The model posits that biological temperament and early-developed psychological vulnerabilities determine whether a learning experience crystallizes into a disorder. This shift from a purely associative account to a vulnerability-stress integration parallels broader movements in psychopathology toward developmental and diathesis-stress frameworks, but Barlow's specific contribution is the explicit three-tier structure and its grounding in emotion theory rather than behaviorist learning theory alone.

A frequent misreading treats the triple vulnerability model as a checklist for diagnosis or as a claim that each vulnerability can be assessed and summed to produce a risk score. Barlow's framework is etiological and probabilistic, not diagnostic. The vulnerabilities are theorized as interacting developmental pathways, not independent risk factors that add up arithmetically. Another misreading assumes the model applies uniformly across all anxiety disorders; in fact, the specific psychological vulnerability is, by definition, disorder-differentiated, and empirical work suggests that mapping specific vulnerabilities to specific disorders remains incomplete . The book is a theoretical treatise on etiology, not a clinical prediction instrument.