Effects of rhythmic eye movements during a virtual reality exposure paradigm for spider-phobic patients.

Rhythmic eye movements performed during eye movement desensitization and reprocessing (EMDR) therapy have been shown to evoke a physiological de-arousal pattern. OBJECTIVES: Here, we examined whether the efficacy of a virtual reality exposure therapy (VRET) paradigm for phobic patients could be improved by adding rhythmic eye movements. DESIGN: Spider-phobic patients (N = 53) were randomly assigned to either a group performing rhythmic eye movements or a control group undergoing exposure without such eye movements. METHODS: During the VRET session, heart rate, electrodermal activity, eye movements, and subjective fear ratings were recorded. Participants underwent behavioural avoidance tests before and after treatment as well as a follow-up 10-14 days later. Questionnaire data were assessed before exposure and at follow-up. RESULTS: There were clear treatment effects in both groups with almost no group differences (i.e., the subjective fear ratings and the skin conductance response). CONCLUSIONS: Contrary to our expectation, the implementation of rhythmic eye movements during virtual exposure did not enhance the effectiveness of the treatment. However, the eye movement group did show a significantly lower heart rate during exposure compared with the control group which might indicate a less stressful treatment. PRACTITIONER POINTS: One-session Virtual Reality Exposure Therapy reduced fear of spiders effectively. Performing rhythmic eye movements during exposure did not enhance therapy effects. Rhythmic eye movements during exposure resulted in lower heart rate than standard exposure.

Diaphragmatic breathing during virtual reality exposure therapy for aviophobia: functional coping strategy or avoidance behavior? a pilot study.

BACKGROUND: Although there is solid evidence for the efficacy of in vivo and virtual reality (VR) exposure therapy for a specific phobia, there is a significant debate over whether techniques promoting distraction or relaxation have impairing or enhancing effects on treatment outcome. In the present pilot study, we investigated the effect of diaphragmatic breathing (DB) as a relaxation technique during VR exposure treatment. METHOD: Twenty-nine patients with aviophobia were randomly assigned to VR exposure treatment either with or without diaphragmatic breathing (six cycles per minute). Subjective fear ratings, heart rate and skin conductance were assessed as indicators of fear during both the exposure and the test session one week later. RESULTS: The group that experienced VR exposure combined with diaphragmatic breathing showed a higher tendency to effectively overcome the fear of flying. Psychophysiological measures of fear decreased and self-efficacy increased in both groups with no significant difference between the groups. CONCLUSIONS: Our findings indicate that diaphragmatic breathing during VR exposure does not interfere with the treatment outcome and may even enhance treatment effects of VR exposure therapy for aviophobic patients. TRIAL REGISTRATION: Retrospectively registered. ClinicalTrials.gov NCT02990208 . Registered 07 December 2016.

Effects of context preexposure and delay until anxiety retrieval on generalization of contextual anxiety.

Animal studies suggest that time delay between acquisition and retrieval of contextual anxiety increases generalization. Moreover, such generalization is prevented by preexposure to the context (CTX), presumably due to an improved representation of such context. We investigated whether preexposure and time-passing modulate generalization of contextual anxiety, in humans. On Day 1, 42 participants (preexposure group) explored two virtual offices, while 41 participants (no-preexposure group) explored a virtual stadium. On Day 2 (24 h later), all participants learned to associate one office (CTX+) with unpredictable unconditioned stimuli (USs), and another office (CTX-) with safety. On Day 3, either 24 h (recent test) or 2 wk (remote test) later, participants revisited CTX- and CTX+ without USs, as well as a generalization context (G-CTX). Results revealed successfully conditioned anxiety and anxiety generalization for ratings (G-CTX was as aversive as CTX+ was), while safety generalization was found for startle responses (G-CTX elicited startle attenuation as CTX- did). Time between learning and testing enhanced generalization as reflected by comparable startle responses to all three offices in the remote test. Contextual preexposure facilitated extinction of explicit conditioned anxiety assessed with ratings. These results suggest that memory trace of a context degrades with passage of time in humans like in animals and, consequently, anxiety generalization enhances. After context preexposure, high cognitive processes seem to be crucially involved in facilitating extinction (or safety) learning.

Reinstatement of contextual anxiety in humans: Effects of state anxiety.

After successful extinction of conditioned fear, the presentation of an unsignaled unconditioned stimulus (US) leads to return of fear, thus, the previously extinguished conditioned stimulus (CS) triggers fear responses again. Human studies on such reinstatement processes are still inconclusive. Some revealed a general increase of fear reactions, both to the fear (CS+) and the safety stimulus (CS-), whereas other studies discovered a differential return of fear with enhanced fear responses to the CS+ only. Moreover, we know little about reinstatement of contextual anxiety, a state of general anxious apprehension and chronic worry. Therefore, the present study investigated reinstatement of contextual anxiety with an ecological valid virtual reality (VR) design. Additionally, we examined whether the current state anxiety might modulate the reinstatement of contextual anxiety. To this end, two groups underwent context conditioning on Day 1, i.e., one context (CXT+) became paired with unpredictable USs, but not the other context (CXT-), and an extinction training on Day 2. On Day 3 a reinstatement test was conducted, i.e., one group (reinstatement group, n=21) received one unsignaled US before testing, whereas the control group (n=21) did not. Only the reinstatement group showed a differential return of contextual anxiety as measured by fear-potentiated startle and anxiety ratings. Interestingly, the reinstatement of fear-potentiated startle was additionally influenced by state anxiety. Conclusively, an anxious state before an unsignaled aversive event might favor a return of contextual anxiety.

Illusory correlations between neutral and aversive stimuli can be induced by outcome aversiveness.

Anxiety is often characterised by an overestimation of the contingency between concern-relevant and aversive stimuli, and an amplified aversiveness of such aversive stimuli. Here we tested whether outcome aversiveness causally enhances contingency estimates. Twenty-four participants were exposed to neutral visual cues which were followed by startle sounds. The loudness and hence the aversiveness of the cue was determined by the cue colour while the likelihood of the startle sound always remained constant (50%). Results indicated an illusory correlation specifically for the cue followed by the most aversive startle sound as reflected in enhanced on-line and a posteriori covariation estimates. This bias was positively correlated with state and trait anxiety. Physiological arousal measured by pupil diameter was enhanced in response to the most aversive startle sound confirming its distinct processing. In conclusion, these results suggest that aversive outcomes may induce illusory correlations, most likely in anxious persons, and explain previous findings of illusory correlations in anxiety disorders.

Is there a negative interpretation bias in depressed patients? An affective startle modulation study.

BACKGROUND/AIMS: Scientists proposed that patients with depression favour negative interpretations when appraising ambiguity. As self-report measures seem prone to response bias, implicit measures of emotional valence should be additionally used. METHODS: A total of 16 patients with depression and 19 controls underwent an acoustic imagery task comprising neutral and negative words, as well as ambiguous words that could be understood either way. Affective startle modulation and direct interrogation were used to assess implicit and explicit emotional valence, respectively. We expected a negative bias for ambiguous words in the patient group, resulting in augmented startle magnitudes and preference for negative interpretations of the ambiguous words in the interrogation. RESULTS: Surprisingly, both groups preferred neutral interpretations and showed augmented startle magnitudes to ambiguous words. Furthermore, both groups displayed an emotional startle potentiation for negative words. CONCLUSION: In summary, our results do not confirm a negative interpretation bias or a blunted emotional response in patients with major depression. The mismatch between self-report and affective startle reaction to ambiguous targets might reflect defensive mobilization or attention effects.

Pain modulation during drives through cold and hot virtual environments.

Evidence exists that virtual worlds reduce pain perception by providing distraction. However, there is no experimental study to show that the type of world used in virtual reality (VR) distraction influences pain perception. Therefore, we investigated whether pain triggered by heat or cold stimuli is modulated by "warm "or "cold " virtual environments and whether virtual worlds reduce pain perception more than does static picture presentation. We expected that cold worlds would reduce pain perception from heat stimuli, while warm environments would reduce pain perception from cold stimuli. Additionally, both virtual worlds should reduce pain perception in general. Heat and cold pain stimuli thresholds were assessed outside VR in 48 volunteers in a balanced crossover design. Participants completed three 4-minute assessment periods: virtual "walks " through (1) a winter and (2) an autumn landscape and static exposure to (3) a neutral landscape. During each period, five heat stimuli or three cold stimuli were delivered via a thermode on the participant's arm, and affective and sensory pain perceptions were rated. Then the thermode was changed to the other arm, and the procedure was repeated with the opposite pain stimuli (heat or cold). We found that both warm and cold virtual environments reduced pain intensity and unpleasantness for heat and cold pain stimuli when compared to the control condition. Since participants wore a head-mounted display (HMD) in both the control condition and VR, we concluded that the distracting value of virtual environments is not explained solely by excluding perception of the real world. Although VR reduced pain unpleasantness, we found no difference in efficacy between the types of virtual world used for each pain stimulus.