Transfer of exposure therapy effects to a threat context not considered during treatment in patients with panic disorder and agoraphobia: Implications for potential mechanisms of change

Exposure traced in daily life: improvements in ecologically assessed social and physical activity following exposure-based psychotherapy for anxiety disorders

BACKGROUND

Although exposure-based cognitive-behavioral therapy for anxiety disorders has frequently been proven effective, only few studies examined whether it improves everyday behavioral outcomes such as social and physical activity.

METHODS

126 participants (85 patients with panic disorder, agoraphobia, social anxiety disorder, or specific phobias, and 41 controls without mental disorders) completed smartphone-based ambulatory ratings (activities, social interactions, mood, physical symptoms) and motion sensor-based indices of physical activity (steps, time spent moving, metabolic activity) at baseline, during, and after exposure-based treatment.

RESULTS

Prior to treatment, patients showed reduced mood and physical activity relative to healthy controls. Over the course of therapy, mood ratings, interactions with strangers and indices of physical activity improved, while reported physical symptoms decreased. Overall results did not differ between patients with primary panic disorder/agoraphobia and social anxiety disorder. Higher depression scores at baseline were associated with larger changes in reported symptoms and mood ratings, but smaller changes in physical activity CONCLUSIONS: Exposure-based treatment initiates increased physical activity, more frequent interaction with strangers, and improvements in everyday mood. The current approach provides objective and fine-graded process and outcome measures that may help to further improve treatments and possibly reduce relapse.

Enhanced Mental Reinstatement of Exposure to Improve Extinction Generalization: A Study on Claustrophobia and MRI Fear

Fear of enclosed spaces prevents many people from receiving magnetic resonance imaging (MRI) scans. Although exposure therapy can effectively treat such fears, reductions in fear during exposure often do not generalize beyond the context in which they took place. This study tested a strategy designed to increase generalization, which involved revisiting the memory of a prior exposure to enhance retrieval of extinction learning. Forty-five participants with claustrophobia that included fear of MRI scans underwent a series of exposures lying inside a narrow cabinet. One week later, participants were randomly assigned to enhanced mental reinstatement (EMR) or control procedures. Prior to entering a mock MRI scanner, EMR participants recalled the memory of exposure training and listened to an audio recording of themselves describing what they learned, whereas control participants recalled a neutral memory. Compared to the control condition, EMR led to significantly reduced heart rate reactivity in the mock MRI scanner, but not self-reported fear or avoidance. There were no differences between conditions in claustrophobia symptoms or MRI fear at 1-month follow-up. Results suggest some benefits of mental reinstatement for improving generalization of gains following exposure training for claustrophobia, with measures of subjective fear and physiological arousal showing discordant outcomes.

Guided reactivation of personal phobic memories prior to exposure exercises prevents the renewal of fear responses in subjects with claustrophobic fears

BACKGROUND AND OBJECTIVES

Basic research suggest behavioral strategies for interferencing the reconsolidation of fear memories to be a promising approach in reducing clinical fears. However, first clinical studies revealed mixed results highlighting the need to identify boundary conditions. We experimentally tested the specific hypothesis that post-retrieval threat exposure prevents context renewal usually observed in protocols without fear memory reactivation.

METHODS

In a preliminary investigation forty-three individuals with claustrophobic fears reactivated the individual phobic memory or not during a guided emotional imagery task and then performed standardized threat exposure to provide new information for updating the original memory. During retests seven and 28 days later, the context was different from that during treatment in half of the subjects.

RESULTS

In those who were guided, the fear memory was successfully reactivated as indexed by increased skin conductance level (SCL) during the imagery of personal scenes relative to neutral scenes. During retests the subjects of the memory non-activation group showed a return of reported fear after context change that, however, was not observed after post-retrieval exposure. In line, autonomic arousal (SCL) decreased over time in the memory reactivation group only if the context changed during retest.

LIMITATIONS

Limited sample size and the inclusion of an analog sample reduce the generalizability of the results.

CONCLUSIONS

The reactivation of fear memory prior to treatment through guided imagery of past personal phobic situations prevented contextual renewal of phobic fears which was observed in those subjects without reactivation of memory.

Mechanisms of Action in Exposure Therapy

PURPOSE OF REVIEW

Exposure therapy is an effective treatment for anxiety-related disorders, but many individuals do not achieve full symptom relief, and return of fear is a common occurrence. Understanding how exposure therapy works enables further development of strategies to improve its effectiveness.

RECENT FINDINGS

Recent studies have examined mechanisms of exposure-based interventions across multiple levels of analysis, from cognitive and behavioral changes that occur during treatment to the neurobiological mechanisms underlying fear extinction. Belief change and reductions in safety behaviors and avoidance mediate symptom improvements during exposure therapy, suggesting plausible cognitive and behavioral mechanisms. On the neural level, increased activation of prefrontal regions during extinction learning is a likely mechanism of exposure. Improved understanding of the biological mechanisms of exposure have led to exciting developments in clinical research, including pharmacological augmentation, though clinical translation of basic research has produced mixed results. Though still in development, such translational research is a promising future direction for exposure-based interventions.

Neural correlates of fear conditioning are associated with treatment-outcomes to behavioral exposure in spider phobia - Evidence from magnetoencephalography

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Magnetoencephalographic effects of fear conditioning predict exposure outcomes.

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No associations between fear ratings of conditioned stimuli and exposure outcomes.

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Prefrontal correlates of safety processing and/or fear inhibition are treatment-relevant.

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Individual neural differences might be a promising predictor of exposure success.

Background

Models of anxiety disorders and the rationale of exposure therapy (ET) are grounded on classical fear conditioning. Yet, it is unclear whether lower fear ratings of conditioned safety versus threat cues and corresponding neural markers of safety-learning and/or fear inhibition assessed before treatment would predict better outcomes of behavioral exposure.

Methods

Sixty-six patients with spider phobia completed pre-treatment clinical and experimental fear conditioning assessments, one session of virtual reality ET, a post-treatment clinical assessment, and a 6-month follow-up assessment. Tilted Gabor gratings served as conditioned stimuli (CS) that were either paired (CS+) or remained unpaired (CS-) with an aversive phobia-related and phobia-unrelated unconditioned stimulus (UCS). CS+/CS- differences in fear ratings and magnetoencephalographic event-related fields (ERFs) were related to percentual symptom reductions from pre- to post-treatment, as assessed via spider phobia questionnaire (SPQ), behavioral avoidance test (BAT), and remission status at 6-month follow-up.

Results

We observed no associations between pre-treatment CS+/CS- differences in fear ratings and any treatment outcome. CS+/CS- differences in source estimations of ERFs revealed that higher CS- activity in bilateral dorsolateral prefrontal cortex (dlPFC) was related with SPQ- and BAT-reductions. Associations between CS+/CS- differences and treatment outcomes were also observed in left ventromedial prefrontal cortex (vmPFC) regions, which additionally revealed associations with the follow-up remission status.

Conclusions

Results provide initial evidence that neural pre-treatment CS+/CS- differences may hold predictive information regarding outcomes of behavioral exposure. Our findings highlight a key role of neural responses to safety cues with potentially inhibitory effects on affect-generating structures during fear conditioning.