Anxiety sensitivity is a known precursor to panic attacks and panic disorder, and involves the misinterpretation of anxiety-related sensations. Aerobic exercise has been shown to reduce generalized anxiety, and may also reduce anxiety sensitivity through exposure to feared physiological sensations. Accordingly, 54 participants with elevated anxiety sensitivity scores completed six 20-min treadmill exercise sessions at either a high-intensity aerobic (n=29) or low-intensity (n=25) level. Self-ratings of anxiety sensitivity, fear of physiological sensations associated with anxiety, and generalized anxiety were obtained at pre-treatment, posttreatment, and one-week follow-up. Results indicated that both high-and low-intensity exercise reduced anxiety sensitivity. However, high-intensity exercise caused more rapid reductions in a global measure of anxiety sensitivity and produced more treatment responders than lowintensity exercise. Only high-intensity exercise reduced fear of anxiety-related bodily sensations. The implications of these findings are discussed.

Exposure to potentially traumatic events is a common occurrence. Most individuals exposed to such an event are resilient or recover rapidly, although some individuals develop psychological problems that warrant treatment. However, a small percentage of individuals seek traditional treatment, thereby calling for novel approaches or methodologies of treatment. The present paper provides a comprehensive and critical review of the extant literature on computerized and internet-basedinterventions (IBIs) for traumatic stress related conditions (i.e., panic disorder, posttraumatic stress disorder/complicated grief, depression, comorbid anxiety and depression, alcohol abuse, smoking cessation). Generally, computerized or IBIs for depression and anxiety are yielding effect sizes that are comparable to traditional psychosocial treatment. Interventions aimed at alcohol and smoking cessation generally have lower effect sizes than do IBIs for anxiety and depression. Most interventions reviewed in this paper included common components (e.g., were developed through a cognitive behavioral framework and included psychoeducation, cognitive restructuring, goal setting, exposure). Therefore, it is possible that these shared features may in part account for symptom reduction. Little is known regarding mechanisms of change. Future directions for novel web-based approaches to treatment are provided.

Current psychiatric nosology depicts posttraumatic stress disorder (PTSD) as a discrete diagnostic category. However, only one study has examined the latent structure of PTSD, and this study suggested that PTSD may be more accurately conceptualized as an extreme reaction to traumatic life events rather than a discrete clinical syndrome. To build on the existing literature base, the present research examined the latent structure of posttraumatic stress reactions by applying three taxometric procedures (MAXEIG, MAMBAC, and L-Mode) to data collected from large nationally representative samples of women (ns = 2684 and 3033) and adolescents (n = 3775). Results consistently provided evidence for a dimensional PTSD solution across samples and statistical procedures. These findings have important implications for the theory, assessment, and investigation of posttraumatic stress reactions.

Anxiety sensitivity, or the belief that anxiety-related sensations can have negative consequences, has been shown to play an important role in the etiology and maintenance of panic disorder and other anxiety-related pathology. Aerobic exercise involves exposure to physiological cues similar to those experienced during anxiety reactions. The present study sought to investigate the efficacy of a brief aerobic exercise intervention for high anxiety sensitivity. Accordingly, 24 participants with high anxiety sensitivity scores (Anxiety Sensitivity Index-Revised scores >28) were randomly assigned to complete either six 20-minute sessions of aerobic exercise or a no-exercise control condition. The results indicated that individuals assigned to the aerobic exercise condition reported significantly less anxiety sensitivity subsequent to exercise, whereas anxiety sensitivity scores among non-exercisers did not significantly change. The clinical research and public health implications of these findings are discussed, and several potential directions for additional research are recommended.