Joan Miquel Gelabert

Virtual Reality Versus Computer-Aided Exposure Treatments for Fear of Flying

Evidence is growing that two modalities of computer-based exposure therapies—virtual reality and computer-aided psychotherapy—are effective in treating anxiety disorders, including fear of flying. However, they have not yet been directly compared. The aim of this study was to analyze the efficacy of three computer-based exposure treatments for fear of flying: virtual reality exposure therapy (VRET), computer-aided exposure with a therapist’s (CAE-T) assistance throughout exposure sessions, and self-administered computer-aided exposure (CAE-SA). A total of 60 participants with flying phobia were randomly assigned to VRET, CAE-T, or CAE-SA. Results indicate that the three interventions were effective in reducing fear of flying at posttreatment and at 1-year follow-up; furthermore, there were no significant differences between them in any of the outcome measure. Large within-group effect sizes were found for all three treatment conditions at both posttreatment and at follow-up. The results suggest that therapist involvement might be minimized during computer-based treatments and that CAE can be as effective as VRET in reducing fear of flying.

Fear induced complexity loss in the electrocardiogram of flight phobics: A multiscale entropy analysis

In this study we explored the changes in the variability and complexity of the electrocardiogram (ECG) of flight phobics (N=61) and a matched non-phobic control group (N=58) when they performed a paced breathing task and were exposed to flight related stimuli. Lower complexity/entropy values were expected in phobics as compared to controls. The phobic system complexity as well as the heart rate variability (HRV) were expected to be reduced by the exposure to fearful stimuli. The multiscale entropy (MSE) analysis revealed lower entropy values in phobics during paced breathing and exposure, and a complexity loss was observed in phobics during exposure to threatening situations. The expected HRV decreases were not found in this study. The discussion is focused on the distinction between variability and complexity measures of the cardiac output, and on the usefulness of the MSE analysis in the field of anxiety disorders.

Vagally mediated heart rate variability and heart rate entropy as predictors of treatment outcome in flight phobia

In the present study a computer-assisted exposure-based treatment was applied to 54 flight phobics and the predictive role of vagally mediated heart rate (HR) variability (high frequency, 0.15-0.4 Hz band power) and heart rate entropy (HR time series sample entropy) on treatment outcome was investigated. Both physiological measures were taken under controlled breathing at 0.2 Hz and during exposure to a fearful sequence of audiovisual stimuli. Hierarchical regression analyses were conducted to assess the predictive power of these variables in these conditions on treatment self-report measures at the end of treatment and at 6 months follow-up, as well as on the behavioral treatment outcome (i.e. flying at the end of treatment). Regression models predicting significant amounts of outcome variance could be built only when HR entropy was added to the HR variability measure in a second step of the regression analyses. HR variability alone was not found to be a good predictor of neither self-reported nor behavioral treatment outcomes.

Resting parietal EEG asymmetry and cardiac vagal tone predict attentional control.

The present study explores both resting cortical EEG asymmetry and vagally-mediated heart rate variability (HRV), as an index for vagal tone, as physiological correlates of self-reported attentional control in a sample of 53 healthy young adults. Regression analyses indicate that higher vagally-mediated HRV and lower right-sided parietal activity in the β2 frequency range (20-30Hz) are significant predictors of larger attentional control. Results are in line with some of the basic features of the neurovisceral integration model and stress the role of parietal areas in attentional control capabilities, thus aiming to consider attentional control as a trait-like disposition.

Slope of change throughout exposure treatment for flight phobia: the role of autonomic flexibility.

This study tested the hypothesis that flight-phobic patients experience change at different rates even when they are receiving identical treatment. Faster within-session rates of change (WSRC) were expected for patients who required fewer exposure sessions. The study also tested the theoretical role of autonomic flexibility on WSRC. High flexibility should be associated with faster rates of change. Thirty-seven flight-phobic patients were successfully treated with a computer-assisted fear of flying treatment. A significant negative correlation was found between total number of sessions and WSRC: The fewer sessions patients attended, the faster their rate of change was. The role of autonomic flexibility was partially supported: A significant correlation between heart rate variability and WSRC revealed that flexible patients improved faster than less-flexible patients.

Can auditory deviant stimuli temporarily suspend cognitive processing? Evidence from patients with anxiety:

While anxiety is typically thought to increase distractibility, this notion mostly derives from studies using emotionally loaded distractors presented in the same modality as the target stimuli and tasks involving crosstalk interference. We examined whether pathological anxiety might also increase distractibility for emotionally neutral irrelevant sounds presented prior to target stimuli in a task where these stimuli do not compete for selection. Patients with anxiety and control participants categorized visual digits preceded by task-irrelevant sounds that changed on rare trials (auditory deviance). Both groups exhibited an equivalent increase in response times following a deviant sound but patients showed a reduction of response accuracy, which was entirely due to an increase in response omissions. We conclude that the involuntary capture of attention by unexpected stimuli may, in patients with anxiety, result in a temporary suspension of cognitive activity.