A randomized controlled dismantling study of Visual Schema Displacement Therapy (VSDT) vs an abbreviated EMDR protocol vs a non-active control condition in individuals with disturbing memories

Background: Visual Schema Displacement Therapy (VSDT) is a novel therapy for the treatment of fears and trauma-related mental health problems including PTSD. VSDT proved to be effective in reducing emotionality of aversive memories in healthy individuals in two previous randomized controlled trials and outperformed both a non-active control condition (CC) and an abbreviated version of EMDR therapy, a well-established first-line treatment for posttraumatic stress disorder. Objectives: In an effort to enhance the understanding concerning the efficacy of VSDT, and to determine its active components, a dismantling study was conducted in individuals with disturbing memories in which the effects of VSDT were tested against EMDR therapy, a non-active CC and three different VSDT-protocols, each excluding or altering a hypothesized active component. Method: Participants (N = 144) were asked to recall an emotional aversive event and were randomly assigned to one of these six interventions, each lasting 8 minutes. Emotional disturbance and vividness of participants' memories were rated before and after the intervention and at one and four-week follow-up. Results: Replicatory Bayesian analyses supported hypotheses in which VSDT was superior to the CC and the EMDR condition in reducing emotionality, both directly after the intervention and at one week follow-up. However, at four-week follow-up, VSDT proved equal to EMDR while both treatments were superior to the CC. Concerning vividness the data also showed support for hypotheses predicting VSDT being equal to EMDR and both being superior to the CC in vividness reduction. Further analyses specifying differences between the abbreviated VSDT protocols detected no differences between these conditions. Conclusion: It remains unclear how VSDT yields its positive effects. Because VSDT appears to be unique and effective in decreasing emotionality of aversive memories, replication of the results in clinical samples is needed.

Making eye movements during imaginal exposure leads to short-lived memory effects compared to imaginal exposure alone

BACKGROUND AND OBJECTIVES

A plethora of eye movement desensitization and reprocessing (EMDR) analogue studies has shown that, in the short term, making eye movements (EM) during brief imaginal exposure ("recall + EM") blurs memories more than just imaginal exposure ("recall only"). Yet, results of the few studies that included a follow-up test are inconsistent. We improved this paradigm's ecological validity by including an extended intervention phase and multiple assessments per phase. We hypothesized that recall + EM results in larger immediate and 24 h reductions in memory vividness, negative valence, and distress than recall alone. We explored the persistence of the effects, as well as the predictive value of memory characteristics and individual differences.

METHODS

Students (N = 100) selected a negative autobiographical memory and were randomized to recall + EM or recall alone; both interventions lasted 32 intervals of 24s. During the interventions they rated the memory after every four intervals.

RESULTS

After 4 × 24s intervention, recall + EM resulted in memory deflation, while recall only caused memory inflation. After the full intervention (i.e., 32 × 24s), both conditions resulted in immediate and 24 h reductions on all outcome measures. Crucially, memory effects in the recall + EM condition partially relapsed 24 h later, while the effects in the recall only condition persisted. Change patterns were hardly explained by predictive variables.

LIMITATIONS

We used a non-clinical sample; replication in clinical samples is warranted.

CONCLUSION

Making EM during imaginal exposure leads to short-lived effects compared to imaginal exposure alone. However, EM may offer a response aid for those who avoid imaginal exposure.

Linguistic dual tasking reduces emotionality, vividness and credibility of voice memories in voice-hearing individuals: Results from a controlled trial

Dual taxation of the working memory during recall is an effective strategy to reduce the emotionality and vividness of visual intrusive memories and potentially changes dysfunctional beliefs associated with the memories. This study tested the hypothesis that dual tasking decreases emotionality, vividness and credibility of auditory intrusive images (i.e., memories of auditory hallucinations) with a two-level (time: pre and post; condition: dual tasking and recall only) within-subjects design. Thirty-seven voice-hearing participants selected two negative voice-hearing experiences. They recalled one of these experiences while performing a lingual dual task (i.e., language game on smartphone app) and recalled one memory without a dual task (in counterbalanced order). During the pre-test and post-test, emotionality and vividness of the voice-hearing memories were rated, as well as the credibility of the voice statements. There was a significantly greater decrease in emotionality, vividness and credibility during dual tasking than during recall only. This study provides proof of principle that the salience and credibility of the content of auditory hallucinations can be reduced by dual tasking; the clinical implications are also discussed.

Dual-tasking during recall of negative memories or during visual perception of images: Effects on vividness and emotionality

BACKGROUND AND OBJECTIVES

Several treatments are effective in reducing symptoms of post-traumatic stress disorder. We tested the effectiveness of an experimental intervention that consists of elements from two of these: virtual reality (VR) exposure therapy and eye movement desensitization and reprocessing. The latter is characterized by a dual-task approach: the patient holds a traumatic memory in mind while simultaneously making voluntary eye movements, resulting in reduced vividness and emotionality of the traumatic memory. If the experimental intervention is effective, it could provide a useful approach for highly avoidant individuals.

METHODS

Participants recalled negative memories induced by a VR paradigm. The experimental group viewed VR screenshots that represented these negative memories while carrying out a dual-task. One control group recalled negative memories while carrying out the same dual-task (a standard dual-task condition) and another merely viewed the VR screenshots. Pre-to-post changes in self-rated memory vividness/emotionality were measured.

RESULTS

The results indicate that viewing a screenshot only was outperformed by both dual-task interventions in terms of reductions in vividness/emotionality. Furthermore, the dual-task interventions had a comparable impact on vividness, but the screenshot variant led to greater decreases in emotionality.

LIMITATIONS

Changes in memory vividness/emotionality were only assessed shortly after the interventions and no measures of avoidance behavior were included in the study.

CONCLUSIONS

Looking at an image in VR that represents a memory while carrying out a dual-task may be at least as effective as recalling the memory during the dual-task. Interestingly, visually supporting a negative memory does not seem to prevent memory degrading by dual-tasking.

Reducing the Emotionality of Auditory Hallucination Memories in Patients Suffering From Auditory Hallucinations

Eye movement desensitization and reprocessing (EMDR) therapy targets emotionally disturbing visual memories of traumatic life events, and may be deployed as an efficacious treatment for posttraumatic stress disorder. A key element of EMDR therapy is recalling an emotionally disturbing visual memory while simultaneously performing a dual task. Previous studies have shown that auditory emotional memories may also become less emotional as a consequence of dual tasking. This is potentially beneficial for psychotic patients suffering from disturbing emotional auditory memories of auditory hallucinations. The present study examined whether and to what extent emotionality of auditory hallucination memories could be reduced by dual tasking. The study also assessed whether a modality matching dual task (recall + auditory taxation) could be more effective than a cross modal dual task (recall + visual taxation). Thirty-six patients suffering from auditory hallucinations were asked to recall an emotionally disturbing auditory memory related to an auditory hallucination, to rate emotionality of the memory, and to recall it under three conditions: two active conditions, i.e., visual taxation (making eye-movements) or auditory taxation (counting aloud), and one control condition (staring at a non-moving dot) counterbalanced in order. Patients re-rated emotionality of the memory after each condition. Results show the memory emotionality of auditory hallucinations was reduced and the active conditions showed stronger effects than the control condition. No modality-specific effect was found: the active conditions had an equal effect.

The Effect of modality specific interference on working memory in recalling aversive auditory and visual memories

Both auditory and visual emotional memories can be made less emotional by loading working memory (WM) during memory recall. Taxing WM during recall can be modality specific (giving an auditory [visuospatial] load during recall of an auditory [visual] memory) or cross modal (an auditory load during visual recall or vice versa). We tested whether modality specific loading taxes WM to a larger extent than cross modal loading. Ninety-six participants undertook a visual and auditory baseline Random Interval Repetition task (i.e. responding as fast as possible to a visual or auditory stimulus by pressing a button). Then, participants recalled a distressing visual and auditory memory, while performing the same visual and auditory Random Interval Repetition task. Increased reaction times (compared to baseline) were indicative of WM loading. Using Bayesian statistics, we compared five models in terms of general and modality specific taxation. There was support for the model describing the effect on WM of dual tasking in general, irrespective of modality specificity, and for the model describing the effect of modality specific loading. Both models combined gained the most support. The results suggest a general effect of dual tasking on taxing WM and a superimposed effect of taxing in matched modality.

Presence and Predictive Value of Obsessive-Compulsive Symptoms in Anxiety and Depressive Disorders

OBJECTIVE

Obsessive-compulsive symptoms (OCS) co-occur frequently with anxiety and depressive disorders, but the nature of their relationship and their impact on severity of anxiety and depressive disorders is poorly understood. In a large sample of patients with anxiety and depressive disorders, we assessed the frequency of OCS, defined as a Young Adult Self-Report Scale-obsessive-compulsive symptoms score >7. The associations between OCS and severity of anxiety and/or depressive disorders were examined, and it was investigated whether OCS predict onset, relapse, and persistence of anxiety and depressive disorders.

METHODS

Data were obtained from the third (at 2-year follow-up) and fourth wave (at 4-year follow-up) of data collection in the Netherlands Study of Anxiety and Depression cohort, including 469 healthy controls, 909 participants with a remitted disorder, and 747 participants with a current anxiety and/or depressive disorder.

RESULTS

OCS were present in 23.6% of the total sample, most notably in those with current combined anxiety and depressive disorders. In patients with a current disorder, OCS were associated with severity of this disorder. Moreover, OCS predicted (1) first onset of anxiety and/or depressive disorders in healthy controls (odds ratio [OR], 5.79; 95% confidence interval [CI], 1.15 to 29.14), (2) relapse in those with remitted anxiety and/or depressive disorders (OR, 2.31; 95% CI, 1.55 to 3.46), and (3) persistence in patients with the combination of current anxiety and depressive disorders (OR, 4.42; 95% CI, 2.54 to 7.70) within the 2-year follow-up period Conclusions: OCS are closely related to both the presence and severity of anxiety and depressive disorders and affect their course trajectories. Hence, OCS might be regarded as a course specifier signaling unfavorable outcomes. This specifier may be useful in clinical care to adapt and intensify treatment in individual patients.

Approach behavior as information

BACKGROUND AND OBJECTIVES

Anxious individuals infer danger from information about physiological responses, anxiety responses, and safety behaviors. This study investigated whether anxious individuals also infer safety from approach behavior.

METHODS

325 students rated the danger they perceived in general and spider-relevant scenarios in which information about objective safety versus objective danger, and approach behavior versus no approach behavior, was varied. A high and low spider fearful group was created with a median split on spider fear.

RESULTS

Participants with a high fear of spiders, compared to participants with low spider fear, rated spider scenarios with approach behavior as safer than spider scenarios without approach behavior. This effect was similar for objectively dangerous and safe spider scenarios. No behavior as information effects were found for general scenarios.

LIMITATIONS

The data were collected in a non-clinical student sample.

CONCLUSIONS

Spider fearful individuals infer safety from approach behavior in spider-relevant scenarios. For spider fearful individuals, approach behavior may add to the beneficial effects of exposure therapy. Future research is needed to investigate whether patients with anxiety disorders also show a tendency to infer safety from approach behavior.

Auditory and Visual Memories in PTSD Patients Targeted with Eye Movements and Counting: The Effect of Modality-Specific Loading of Working Memory

Introduction: Eye movement desensitization and reprocessing (EMDR) therapy is an evidence-based treatment for post-traumatic stress disorder (PTSD). A key element of this therapy is simultaneously recalling an emotionally disturbing memory and performing a dual task that loads working memory. Memories targeted with this therapy are mainly visual, though there is some evidence that auditory memories can also be targeted. Objective: The present study tested whether auditory memories can be targeted with EMDR in PTSD patients. A second objective was to test whether taxing the patient (performing a dual task while recalling a memory) in a modality specific way (auditory demanding for auditory memories and visually demanding for visual memories) was more effective in reducing the emotionality experienced than taxing in cross-modality. Methods: Thirty-six patients diagnosed with PTSD were asked to recall two disturbing memories, one mainly visual, the other one mainly auditory. They rated the emotionality of the memories before being exposed to any condition. Both memories were then recalled under three alternating conditions [visual taxation, auditory taxation, and a control condition (CC), which comprised staring a non-moving dot] - counterbalanced in order - and patients rerated emotionality after each condition. Results: All three conditions were equally effective in reducing the emotionality of the auditory memory. Auditory loading was more effective in reducing the emotionality in the visual intrusion than the CC, but did not differ from the visual load. Conclusion: Auditory and visual aversive memories were less emotional after working memory taxation (WMT). This has some clinical implications for EMDR therapy, where mainly visual intrusions are targeted. In this study, there was no benefit of modality specificity. Further fundamental research should be conducted to specify the best protocol for WMT.

Disconfirming contamination-related threat beliefs by exposure plus safety behavior

BACKGROUND AND OBJECTIVES

Safety behavior (SB) is detrimental to the beneficial effects of exposure, because it prevents patients from obtaining evidence that disconfirms their excessive threat beliefs. However, previous studies showed that cleaning SB during exposure to a contaminant does not prevent a reduction in feelings of contamination, fear of contamination, danger, and disgust (CFDD). We aimed to directly examine the effect of SB during exposure to a contaminant on threat beliefs associated with CFDD.

METHOD

Healthy participants were randomly assigned to one of three groups: repeated exposure to a contaminant whilst abstaining from SB (exposure plus response prevention; E + RP); with the use of disinfectant wipes after each instance of exposure (exposure plus SB; E + SB); or no exposure or safety behavior (control condition). Participants identified their threat belief associated with the contaminant and rated CFDD and the degree to which they believed their threat belief at the pre- and post-test.

RESULTS

The E + RP and E + SB condition resulted in a larger decrease of CFDD and threat belief ratings than the control condition, whereas these reductions did not differ between the E + RP and E + SB condition.

LIMITATIONS

Results were obtained from a nonclinical sample, and with a single session of exposure.

CONCLUSION

Cleaning SB did not impede the beneficial effects of exposure.

Modification of episodic memories by novel learning: a failed replication study

Background: After reactivation, memories can become unstable and sensitive to modification before they are restored into long-term memory. Using behavioural manipulations, reactivated memories may be disrupted via the mechanism of interference (i.e. novel learning). In a laboratory study, Wichert et al. (2013a) showed that new learning after reactivation changed episodic memory, while new learning alone or reactivation alone did not. Objective: Given the potential clinical application of such a procedure in trauma-focused psychological treatments, such as CBT or EMDR, the aim of this study was to replicate Wichert et al. Method: On Day 1, participants (N = 96) viewed and recalled a series of emotional and non-emotional pictures. Then, participants were randomized to one of four groups. One week later, on Day 8, Group 1 reactivated the previously learned pictures and learned new pictures. To control for specific effects of reactivation or new learning, Group 2 only reactivated the previously learned pictures, and Group 3 only learned new pictures. Group 4 received no reactivation and no new learning. On Day 9, all groups indicated for each picture out of a series whether they had seen it on Day 1. Results: The data were analysed using Bayesian hypothesis testing, which allows for quantifying the evidence in favour of the alternative and the null hypothesis. In general, results showed that Group 1 recognized fewer pictures from Day 1 compared to Groups 2 and 4 on Day 9. However, the expected difference between new learning following reactivation (i.e. Group 1) and new learning alone (i.e. Group 3) was not substantially supported by the data for any of our dependent measures. Conclusions: We replicated some of the findings by Wichert et al., but did not find substantial support for the critical difference between new learning following reactivation and new learning alone.

Exploring expectation effects in EMDR: does prior treatment knowledge affect the degrading effects of eye movements on memories?

Background: Eye movement desensitization and reprocessing (EMDR) is an effective psychological treatment for posttraumatic stress disorder. Recalling a memory while simultaneously making eye movements (EM) decreases a memory's vividness and/or emotionality. It has been argued that non-specific factors, such as treatment expectancy and experimental demand, may contribute to the EMDR's effectiveness. Objective: The present study was designed to test whether expectations about the working mechanism of EMDR would alter the memory attenuating effects of EM. Two experiments were conducted. In Experiment 1, we examined the effects of pre-existing (non-manipulated) knowledge of EMDR in participants with and without prior knowledge. In Experiment 2, we experimentally manipulated prior knowledge by providing participants without prior knowledge with correct or incorrect information about EMDR's working mechanism. Method: Participants in both experiments recalled two aversive, autobiographical memories during brief sets of EM (Recall+EM) or keeping eyes stationary (Recall Only). Before and after the intervention, participants scored their memories on vividness and emotionality. A Bayesian approach was used to compare two competing hypotheses on the effects of (existing/given) prior knowledge: (1) Prior (correct) knowledge increases the effects of Recall+EM vs. Recall Only, vs. (2) prior knowledge does not affect the effects of Recall+EM. Results: Recall+EM caused greater reductions in memory vividness and emotionality than Recall Only in all groups, including the incorrect information group. In Experiment 1, both hypotheses were supported by the data: prior knowledge boosted the effects of EM, but only modestly. In Experiment 2, the second hypothesis was clearly supported over the first: providing knowledge of the underlying mechanism of EMDR did not alter the effects of EM. Conclusions: Recall+EM appears to be quite robust against the effects of prior expectations. As Recall+EM is the core component of EMDR, expectancy effects probably contribute little to the effectiveness of EMDR treatment.

Comparisons of eye movements and matched changing visual input

BACKGROUND AND OBJECTIVES

During EMDR trauma therapy, performing EM taxes WM, and simultaneously recalled memories become less vivid. It has been proposed that this WM occupation results from CVI which occurs during EM. This study sought to compare the effects of EM on memory to a task presenting identical visual stimulus to stationary eyes..

METHOD

In Study 1, participants recorded RT while performing two tasks: EM, and a task with visually identical images displayed on screen. In Study 2, these same tasks were performed while simultaneously recalling negative emotional memories.

RESULTS

Study 1 found RT was slowest in the EM condition, while RT in the CVI condition was still slower than in the control condition. Study 2 found decreases in memory vividness and emotionality after EM, while after CVI there was a small decrease in negativity which was not greater than in the control..

LIMITATIONS

Neither study included EM with no visual input; conclusions cannot be made about the effect of motor movement on WM taxation or recall. As neither study was conducted with trauma patients, it is unknown if the observed effects would be comparable in the population for which EMDR is intended.

CONCLUSIONS

Performing EM taxes more WM resources and has greater impact on both memory vividness and emotionality than matched CVI. This demonstrates that the effects observed in EMDR treatment are the result of more than occupying WM systems with visual stimuli alone..

Check, check, double check: Investigating memory deterioration within multiple sessions of repeated checking

BACKGROUND AND OBJECTIVES

Extensive research has shown that repeated checking causes memory distrust. Therefore, it has been suggested that people may subsequently get into a vicious cycle of decreased memory confidence and increased checking behavior, which may play a role in the maintenance and development of OCD. This study investigated in two experiments how repeated checking influences memory distrust over multiple checking episodes.

METHODS

In experiment 1, 70 healthy undergraduates performed two sessions of a virtual checking task with a 30 min break in between. In experiment 2, 41 healthy undergraduates performed two sessions of the checking task on a real kitchen stove and sink.

RESULTS

Results of experiment 1 showed that memory confidence for checking the stove decreased after repeated checking in session 1, and remained low in session 2, but memory vividness and detail decreased in both sessions and recovered in between. In experiment 2, all three meta-memory ratings for checking the stove decreased after repeated checking in both sessions, but recovered in between.

LIMITATIONS

Future research may include patients with OCD. To further investigate the development of memory distrust over time, more checking episodes may be included and the time between sessions may be increased. Although replication is needed, the findings of experiment 2 seem more informative.

CONCLUSIONS

Repeated checking may decrease memory vividness and detail (and, in turn, presumably also decrease memory confidence) each time this counterproductive strategy is used, which may have implications for using this paradigm as a behavioral experiment in cognitive-behavioral therapy.

Degrading emotional memories induced by a virtual reality paradigm

BACKGROUND AND OBJECTIVES

In Eye Movement and Desensitization and Reprocessing (EMDR) therapy, a dual-task approach is used: patients make horizontal eye movements while they recall aversive memories. Studies showed that this reduces memory vividness and/or emotionality. A strong explanation is provided by working memory theory, which suggests that other taxing dual-tasks are also effective. Experiment 1 tested whether a visuospatial task which was carried out while participants were blindfolded taxes working memory. Experiment 2 tested whether this task degrades negative memories induced by a virtual reality (VR) paradigm.

METHODS

In experiment 1, participants responded to auditory cues with or without simultaneously carrying out the visuospatial task. In experiment 2, participants recalled negative memories induced by a VR paradigm. The experimental group simultaneously carried out the visuospatial task, and a control group merely recalled the memories. Changes in self-rated memory vividness and emotionality were measured.

RESULTS

The slowing down of reaction times due to the visuospatial task indicated that its cognitive load was greater than the load of the eye movements task in previous studies. The task also led to reductions in emotionality (but not vividness) of memories induced by the VR paradigm.

LIMITATIONS

Weaknesses are that only males were tested in experiment 1, and the effectiveness of the VR fear/trauma induction was not assessed with ratings of mood or intrusions in experiment 2.

CONCLUSIONS

The results suggest that the visuospatial task may be applicable in clinical settings, and the VR paradigm may provide a useful method of inducing negative memories.

Perseveration induces dissociative uncertainty in obsessive-compulsive disorder

BACKGROUND AND OBJECTIVES

Obsessive compulsive (OC)-like perseveration paradoxically increases feelings of uncertainty. We studied whether the underlying mechanism between perseveration and uncertainty is a reduced accessibility of meaning ('semantic satiation').

METHODS

OCD patients (n = 24) and matched non-clinical controls (n = 24) repeated words 2 (non-perseveration) or 20 times (perseveration). They decided whether this word was related to another target word. Speed of relatedness judgments and feelings of dissociative uncertainty were measured. The effects of real-life perseveration on dissociative uncertainty were tested in a smaller subsample of the OCD group (n = 9).

RESULTS

Speed of relatedness judgments was not affected by perseveration. However, both groups reported more dissociative uncertainty after perseveration compared to non-perseveration, which was higher in OCD patients. Patients reported more dissociative uncertainty after 'clinical' perseveration compared to non-perseveration..

LIMITATIONS

Both parts of this study are limited by some methodological issues and a small sample size.

CONCLUSIONS

Although the mechanism behind 'perseveration → uncertainty' is still unclear, results suggest that the effects of perseveration are counterproductive.

The effects of eye movements on emotional memories: using an objective measure of cognitive load

BACKGROUND

Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. The working memory (WM) theory explains its efficacy: recall of an aversive memory and making eye movements (EM) both produce cognitive load, and competition for the limited WM resources reduces the memory's vividness and emotionality. The present study tested several predictions from WM theory.

OBJECTIVE

We hypothesized that 1) recall of an aversive autobiographical memory loads WM compared to no recall, and 2) recall with EM reduces the vividness, emotionality, and cognitive load of recalling the memory more than only recall or only cognitive effort (i.e., recall of an irrelevant memory with EM).

METHOD

Undergraduates (N=108) were randomly assigned to one of three conditions: 1) recall relevant memory with EM, 2) recall relevant memory without EM, and 3) recall irrelevant memory with EM. We used a random interval repetition task to measure the cognitive load of recalling the memory. Participants responded to randomly administered beeps, with or without recalling the memory. The degree to which participants slow down during recall provides an index of cognitive load. We measured the cognitive load and self-reported vividness and emotionality before, halfway through (8×24 s), and after (16×24 s) the intervention.

RESULTS

Reaction times slowed down during memory recall compared to no recall. The recall relevant with EM condition showed a larger decrease in self-reported vividness and emotionality than the control conditions. The cognitive load of recalling the memory also decreased in this condition but not consistently more than in the control conditions.

CONCLUSIONS

Recall of an aversive memory loads WM, but drops in vividness and emotionality do not immediately reduce the cognitive load of recalling the memory. More research is needed to find objective measures that could capture changes in the quality of the memory.

Patients With Obsessive-Compulsive Disorder Check Excessively in Response to Mild Uncertainty

Patients with obsessive-compulsive disorder (OCD) not only respond to obsessions with perseverative checking, but also engage in more general checking, irrespective of their obsessive concerns. This study investigated whether general checking is specific to OCD and exacerbated when only mild uncertainty is induced. Thirty-one patients with OCD, 26 anxiety- and 31 healthy controls performed a visual search task with eye-tracking and indicated in 50 search displays whether a target was "present" or "absent". Target-present trials were unambiguous, whereas target-absent trials induced mild uncertainty, because participants had to rely on not overlooking the target. Checking behavior was measured by assessing search time and the number of fixations, measured with an eye-tracker. Results showed that in both target-present and target-absent trials patients with OCD searched longer and made more fixations than healthy and anxiety controls. However, the difference in checking behavior between patients with OCD and the control groups was larger in target-absent trials (where mild uncertainty was induced). Anxiety and healthy controls did not differ in checking behavior. Thus, mild uncertainty appears to specifically promote checking in patients with OCD, which has implications for treatment.

Blurring emotional memories using eye movements: individual differences and speed of eye movements

BACKGROUND

In eye movement desensitization and reprocessing (EMDR), patients make eye movements (EM) while recalling traumatic memories. Making EM taxes working memory (WM), which leaves less resources available for imagery of the memory. This reduces memory vividness and emotionality during future recalls. WM theory predicts that individuals with small working memory capacities (WMCs) benefit more from low levels of taxing (i.e., slow EM) whereas individuals with large WMC benefit more from high levels of taxing (i.e., fast EM).

OBJECTIVE

We experimentally examined and tested four prespecified hypotheses regarding the role of WMC and EM speed in reducing emotionality and vividness ratings: 1) EM-regardless of WMC and EM speed-are more effective compared to no dual task, 2) increasing EM speed only affects the decrease in memory ratings irrespective of WMC, 3) low-WMC individuals-compared to high-WMC individuals-benefit more from making either type of EM, 4) the EM intervention is most effective when-as predicted by WM theory-EM are adjusted to WMC.

METHOD

Undergraduates with low (n=31) or high (n=35) WMC recalled three emotional memories and rated vividness and emotionality before and after each condition (recall only, recall + slow EM, and recall + fast EM).

RESULTS

Contrary to the theory, the data do not support the hypothesis that EM speed should be adjusted to WMC (hypothesis 4). However, the data show that a dual task in general is more effective in reducing memory ratings than no dual task (hypothesis 1), and that a more cognitively demanding dual task increases the intervention's effectiveness (hypothesis 2).

CONCLUSIONS

Although adjusting EM speed to an individual's WMC seems a straightforward clinical implication, the data do not show any indication that such a titration is helpful.

Desensitizing Addiction: Using Eye Movements to Reduce the Intensity of Substance-Related Mental Imagery and Craving

Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. During this treatment, patients recall traumatic memories while making horizontal eye movements (EM). Studies have shown that EM not only desensitize negative memories but also positive memories and imagined events. Substance use behavior and craving are maintained by maladaptive memory associations and visual imagery. Preliminary findings have indicated that these mental images can be desensitized by EMDR techniques. We conducted two proof-of-principle studies to investigate whether EM can reduce the sensory richness of substance-related mental representations and accompanying craving levels. We investigated the effects of EM on (1) vividness of food-related mental imagery and food craving in dieting and non-dieting students and (2) vividness of recent smoking-related memories and cigarette craving in daily smokers. In both experiments, participants recalled the images while making EM or keeping eyes stationary. Image vividness and emotionality, image-specific craving and general craving were measured before and after the intervention. As a behavioral outcome measure, participants in study 1 were offered a snack choice at the end of the experiment. Results of both experiments showed that image vividness and craving increased in the control condition but remained stable or decreased after the EM intervention. EM additionally reduced image emotionality (experiment 2) and affected behavior (experiment 1): participants in the EM condition were more inclined to choose healthy over unhealthy snack options. In conclusion, these data suggest that EM can be used to reduce intensity of substance-related imagery and craving. Although long-term effects are yet to be demonstrated, the current studies suggest that EM might be a useful technique in addiction treatment.

Speed Matters: Relationship between Speed of Eye Movements and Modification of Aversive Autobiographical Memories

Eye movement desensitization and reprocessing (EMDR) is an efficacious treatment for post-traumatic stress disorder. In EMDR, patients recall a distressing memory and simultaneously make eye movements (EM). Both tasks are considered to require limited working memory (WM) resources. Because this leaves fewer resources available for memory retrieval, the memory should become less vivid and less emotional during future recall. In EMDR analogue studies, a standardized procedure has been used, in which participants receive the same dual task manipulation of 1 EM cycle per second (1 Hz). From a WM perspective, the WM taxation of the dual task might be titrated to the WM taxation of the memory image. We hypothesized that highly vivid images are more affected by high WM taxation and less vivid images are more affected by low WM taxation. In study 1, 34 participants performed a reaction time task, and rated image vividness, and difficulty of retrieving an image, during five speeds of EM and no EM. Both a high WM taxing frequency (fast EM; 1.2 Hz) and a low WM taxing frequency (slow EM; 0.8 Hz) were selected. In study 2, 72 participants recalled three highly vivid aversive autobiographical memory images (n = 36) or three less vivid images (n = 36) under each of three conditions: recall + fast EM, recall + slow EM, or recall only. Multi-level modeling revealed a consistent pattern for all outcome measures: recall + fast EM led to less emotional, less vivid and more difficult to retrieve images than recall + slow EM and recall only, and the effects of recall + slow EM felt consistently in between the effects of recall + fast EM and recall only, but only differed significantly from recall + fast EM. Crucially, image vividness did not interact with condition on the decrease of emotionality over time, which was inconsistent with the prediction. Implications for understanding the mechanisms of action in memory modification and directions for future research are discussed.

Updated meta-analysis of classical fear conditioning in the anxiety disorders

The aim of the current study was twofold: (1) to systematically examine differences in fear conditioning between anxiety patients and healthy controls using meta-analytic methods, and (2) to examine the extent to which study characteristics may account for the variability in findings across studies. Forty-four studies (published between 1920 and 2013) with data on 963 anxiety disordered patients and 1,222 control subjects were obtained through PubMed and PsycINFO, as well as from a previous meta-analysis on fear conditioning (Lissek et al.). Results demonstrated robustly increased fear responses to conditioned safety cues (CS-) in anxiety patients compared to controls during acquisition. This effect may represent an impaired ability to inhibit fear in the presence of safety cues (CS-) and/or may signify an increased tendency in anxiety disordered patients to generalize fear responses to safe stimuli resembling the conditioned danger cue (CS+). In contrast, during extinction, patients show stronger fear responses to the CS+ and a trend toward increased discrimination learning (differentiation between the CS+ and CS-) compared to controls, indicating delayed and/or reduced extinction of fear in anxiety patients. Finally, none of the included study characteristics, such as the type of fear measure (subjective vs. psychophysiological index of fear), could account significantly for the variance in effect sizes across studies. Further research is needed to investigate the predictive value of fear extinction on treatment outcome, as extinction processes are thought to underlie the beneficial effects of exposure treatment in anxiety disorders.

Taxing Working Memory during Retrieval of Emotional Memories Does Not Reduce Memory Accessibility When Cued with Reminders

Earlier studies have shown that when individuals recall an emotional memory while simultaneously doing a demanding dual-task [e.g., playing Tetris, mental arithmetic, making eye movements (EM)], this reduces self-reported vividness and emotionality of the memory. These effects have been found up to 1 week later, but have largely been confined to self-report ratings. This study examined whether this dual-tasking intervention reduces memory performance (i.e., accessibility of emotional memories). Undergraduates (N = 60) studied word-image pairs and rated the retrieved image on vividness and emotionality when cued with the word. Then they viewed the cues and recalled the images with or without making EM. Finally, they re-rated the images on vividness and emotionality. Additionally, fragments from images from all conditions were presented and participants identified which fragment was paired earlier with which cue. Findings showed no effect of the dual-task manipulation on self-reported ratings and latency responses. Several possible explanations for the lack of effects are discussed, but the cued recall procedure in our experiment seems to explain the absence of effects best. The study demonstrates boundaries to the effects of the "dual-tasking" procedure.

How eye movements in EMDR work: changes in memory vividness and emotionality

BACKGROUND AND OBJECTIVES

Eye movements (EM) during recall of an aversive memory is a treatment element unique to Eye Movement Desensitization and Reprocessing (EMDR). Experimental studies have shown that EM reduce memory vividness and/or emotionality shortly after the intervention. However, it is unclear whether the immediate effects of the intervention reflect actual changes in memory. The aim of this study was to test whether immediate reductions in memory vividness and emotionality persist at a 24 h follow up and whether the magnitude of these effects is related to the duration of the intervention.

METHODS

Seventy-three undergraduates recalled two negative autobiographical memories, one with EM ("recall with EM") and one without ("recall only"). Half of participants recalled each memory for four periods of 24 s, the other half for eight periods of 24 s. Memory vividness/emotionality were self-rated at a pre-test, an immediate post-test, and a 24 h follow-up test.

RESULTS

In both duration groups, recall with EM, but not recall only, caused an immediate decrease in memory vividness. There were no immediate reductions in memory emotionality. Furthermore, only the 'eight periods' group showed that recall with EM, but not recall only, caused a decrease in both memory emotionality and memory vividness from the pre-test to the follow-up.

LIMITATIONS

Only self-report measures were used.

CONCLUSIONS

The findings suggest that recall with EM causes 24-h changes in memory vividness/emotionality, which may explain part of the EMDR treatment effect, and these effects are related to intervention duration.

Anger: cause or consequence of posttraumatic stress? A prospective study of Dutch soldiers

Many studies have shown that individuals with posttraumatic stress disorder (PTSD) experience more anger over time and across situations (i.e., trait anger) than trauma-exposed individuals without PTSD. There is a lack of prospective research, however, that considers anger levels before trauma exposure. The aim of this study was to prospectively assess the relationship between trait anger and PTSD symptoms, with several known risk factors, including baseline symptoms, neuroticism, and stressor severity in the model. Participants were 249 Dutch soldiers tested approximately 2 months before and approximately 2 months and 9 months after their deployment to Afghanistan. Trait anger and PTSD symptom severity were measured at all assessments. Structural equation modeling including cross-lagged effects showed that higher trait anger before deployment predicted higher PTSD symptoms 2 months after deployment (β = .36), with stressor severity and baseline symptoms in the model, but not with neuroticism in the model. Trait anger at 2 months postdeployment did not predict PTSD symptom severity at 9 months, and PTSD symptom severity 2 months postdeployment did not predict subsequent trait anger scores. Findings suggest that trait anger may be a pretrauma vulnerability factor for PTSD symptoms, but does not add variance beyond the effect of neuroticism.

Does repeated ticking maintain tic behavior? An experimental study of eye blinking in healthy individuals

Tics in Tourette Syndrome (TS) are often preceded by 'premonitory urges': annoying feelings or bodily sensations. We hypothesized that, by reducing annoyance of premonitory urges, tic behaviour may be reinforced. In a 2X2 experimental design in healthy participants, we studied the effects of premonitory urges (operationalized as air puffs on the eye) and tic behaviour (deliberate eye blinking after a puff or a sound) on changes in subjective evaluation of air puffs, and EMG responses on the m. orbicularis oculi. The experimental group with air puffs+ blinking experienced a decrease in subjective annoyance of the air puff, but habituation of the EMG response was blocked and length of EMG response increased. In the control groups (air puffs without instruction to blink, no air puffs), these effects were absent. When extrapolating to the situation in TS patients, these findings suggest that performance of tics is reinforced by reducing the subjective annoyance of premonitory urges, while simultaneously preventing habituation or even inducing sensitisation of the physiological motor response.

Clinical relevance of comorbidity in obsessive compulsive disorder: the Netherlands OCD Association study

BACKGROUND

This study describes lifetime and current rates of comorbidity, its onset and its consequences in a large clinical sample of patients with obsessive compulsive disorder (OCD). A wide range of risk factors and clinical characteristics were also examined to determine whether pure OCD is different from OCD with current comorbidity. Finally, the temporal sequencing of the disorders was examined.

METHOD

Data were obtained from the Netherlands Obsessive Compulsive Disorder Association (NOCDA) study. A sample of 382 participants with current OCD (during the past month) was evaluated.

RESULTS

Current comorbidity occurred in 55% of patients with OCD, while 78% suffered from lifetime comorbidity. Comorbidity is associated with more severe OCD, anxiety and depressive symptoms and more negative consequences on daily life. Multiple comorbid disorders often precede OCD and influence both its course and severity. Childhood trauma and neuroticism are vulnerability factors for the development of multiple comorbid disorders in OCD.

LIMITATIONS

It should be noted that causal inferences about the association between risk factors and OCD are precluded since our results were based on cross-sectional data.

CONCLUSION

(Multiple) comorbidity in OCD is clinically relevant since it is associated with a specific pattern of vulnerability, with greater chronicity, with more severe OCD and more negative consequences on daily life. This indicates that the diagnosis and treatment of all comorbid disorders is clinically relevant, and clinicians should be especially aware of multiple disorders in cases of childhood trauma and high levels of neuroticism. Primary OCD has a different developmental and comorbidity pattern compared to secondary OCD.

On feeding those hungry for praise: person praise backfires in children with low self-esteem

Child-rearing experts have long believed that praise is an effective means to help children with low self-esteem feel better about themselves. But should one praise these children for who they are, or for how they behave? Study 1 (N = 357) showed that adults are inclined to give children with low self-esteem more person praise (i.e., praise for personal qualities) but less process praise (i.e., praise for behavior) than they give children with high self-esteem. This inclination may backfire, however. Study 2 (N = 313; M(age) = 10.4 years) showed that person praise, but not process praise, predisposes children, especially those with low self-esteem, to feel ashamed following failure. Consistent with attribution theory, person praise seems to make children attribute failure to the self. Together, these findings suggest that adults, by giving person praise, may foster in children with low self-esteem the very emotional vulnerability they are trying to prevent.

Susceptibility to long-term misinformation effect outside of the laboratory

OBJECTIVE

To test the effect of misinformation outside of the laboratory and to explore correlates of the effect, including arousal, cognitive ability, and neuroticism.

METHOD

About 2 months before deployment to Afghanistan, 249 soldiers enrolled in this study, which was embedded in a larger project. Two months after deployment, participants were interviewed about stressors on deployment and they received subtle misinformation about a fictional event on deployment. Seven months later, they were retested, and completed a questionnaire about events on deployment.

RESULTS

At 9 months, a total of 26% of participants reported that they had experienced the fictional event, although 7 months earlier they said they had not experienced it. Logistic regression analyses revealed that lower cognitive ability and a combination of high arousal and more stressors on deployment were related to higher susceptibility to the misinformation effect.

CONCLUSIONS

Results suggest that information provided by another source may be incorporated into related autobiographical memory, particularly for individuals with lower cognitive ability, high arousal at the time of encoding the information and more related experiences.

Ironic effects of compulsive perseveration

Individuals with obsessive-compulsive disorder (OCD) exhibit perseverative behaviours, like checking, to reduce uncertainty, but perseveration paradoxically enhances uncertainty. It is unclear what mechanism might be responsible. We hypothesised that perseverative OC-like behaviour produces "semantic satiation" and interferes with the accessibility of meaning. Healthy participants repeated 20 types of OC-like checking behaviour nonperseveratively (2 times) or perseveratively (20 times). Afterwards, they decided as quickly as possible whether a picture was semantically related to the checked object. The nonperseverative condition showed spreading of activation: Judgements were faster for related than for unrelated objects and pictures. The effect was blocked in the perseverative condition, where reaction times for related and unrelated items were similar. The results suggest that the ironic effects of compulsive perseveration are due to interference with spreading of activation.

On EMDR: eye movements during retrieval reduce subjective vividness and objective memory accessibility during future recall

In eye movement desensitization and reprocessing (EMDR), a treatment for post-traumatic stress disorder (PTSD), patients make eye movements (EM) during trauma recall. Earlier experimental studies found that EM during recall reduces memory vividness during future recalls, and this was taken as laboratory support for the underlying mechanism of EMDR. However, reduced vividness was assessed with self-reports that may be affected by demand characteristics. We tested whether recall+EM also reduces memory vividness on a behavioural reaction time (RT) task. Undergraduates (N=32) encoded two pictures, recalled them, and rated their vividness. In the EM group, one of the pictures was recalled again while making EM. In the no-EM group one of the pictures was recalled without EM. Then fragments from both the recalled and non-recalled pictures, and new fragments were presented and participants rated whether these were (or were not) seen before. Both pictures were rated again for vividness. In the EM group, self-rated vividness of the recalled+EM picture decreased, relative to the non-recalled picture. In the no-EM group there was no difference between the recalled versus non-recalled picture. The RT task showed the same pattern. Reduction of memory vividness due to recall+EM is also evident from non-self-report data.

Clinical relevance of comorbidity in anxiety disorders: a report from the Netherlands Study of Depression and Anxiety (NESDA)

BACKGROUND

To study the clinical relevance of type of comorbidity and number of comorbid disorders in anxiety disorders. Four groups were compared according to sociodemographic-, vulnerability- and clinical factors: single anxiety disorder, anxiety-anxiety comorbidity, anxiety-depressive comorbidity and "double" comorbidity (i.e. anxiety and depressive comorbidity).

METHODS

Data were obtained from the Netherlands Study of Anxiety and Depression (NESDA). A sample of 1004 participants with a current anxiety disorder was evaluated.

RESULTS

As compared with single anxiety, anxiety-anxiety comorbidity was associated with higher severity, greater chronicity and more treatment. Anxiety-anxiety comorbidity was associated with an earlier age of onset and a more chronic course compared with anxiety-depressive comorbidity, while anxiety-depressive comorbidity was associated with more severe symptoms and more impaired functioning than anxiety-anxiety comorbidity. "Double" comorbidity was associated with higher severity, greater chronicity, more treatment and increased disability. Sociodemographic and vulnerability factors were comparable among the four groups. Limitations A prospective design would be more appropriate to study the outcome. In this study no distinction was made between whether depression or anxiety disorder preceded the current anxiety disorder.

CONCLUSIONS

It is clinical relevant to diagnose and treat comorbidity among anxiety disorders as it is associated with higher severity and more chronicity. Whereas anxiety-anxiety comorbidity has an earlier age of onset and a more chronic course, anxiety-depressive comorbidity leads to more treatment and impaired functioning. "Double" comorbidity leads to even more severity, chronicity and impairment functioning compared with both anxiety-anxiety and anxiety-depressive comorbidity.

The role of self-concept clarity in prolonged grief disorder

Three studies using independent samples of bereaved individuals were conducted to examine the association of self-concept clarity (SCC) with symptoms of prolonged grief disorder (PGD), a debilitating syndrome than can develop after bereavement. Study 1 (N = 67) showed that lower SCC was associated with greater PGD severity, independent from self-concept content change. Using a retrospective design, Study 2 (N = 116) showed that a loss can coincide with a decline in SCC, the magnitude of which was associated with acute PGD severity. Study 2 also showed that the maintenance of PGD symptoms over time was associated with a smaller increase in SCC beyond the first month of bereavement and not with this acute SCC decline. Using a prospective-longitudinal design, Study 3 (N = 121) showed that the impact of lower SCC on concurrent and prospective PGD severity was mediated by lower self-esteem, depressive avoidance, and rumination. Moreover, lower initial SCC predicted PGD severity 6 months later.

EMDR and mindfulness. Eye movements and attentional breathing tax working memory and reduce vividness and emotionality of aversive ideation

BACKGROUND AND OBJECTIVES

Eye Movement Desensitization and Reprocessing (EMDR) and Mindfulness-Based Cognitive Therapy (MBCT) are effective in reducing the subjective impact of negative ideation. In both treatments, patients are encouraged to engage in a dual-task (eye movements (EM) in the case of EMDR and attentional breathing (AB) in the case of MBCT) while they experience negative thoughts or images. Working memory theory explains the effects of EM by suggesting that it taxes limited working memory resources, thus rendering the image less vivid and emotional. It was hypothesized that both AB and EM tax working memory and that both reduce vividness and emotionality of negative memories.

METHODS

Working memory taxation by EM and AB was assessed in healthy volunteers by slowing down of reaction times. In a later session, participants retrieved negative memories during recall only, recall + EM and recall + AB (study 1). Under improved conditions the study was replicated (study 2).

RESULTS

In both studies and to the same degree, attentional breathing and eye movements taxed working memory. Both interventions reduced emotionality of memory in study 1 but not in study 2 and reduced vividness in study 2 but not in study 1.

LIMITATIONS

EMDR is more than EM and MBCT is more than AB. Memory effects were assessed by self reports.

CONCLUSIONS

EMDR and MBCT may (partly) derive their beneficial effects from taxing working memory during recall of negative ideation.

Obsessive-compulsive-like reasoning makes an unlikely catastrophe more credible

When obsessive-compulsive (OC) patients are confronted with disorder-relevant situations, they tend to reason in chains of small steps between the current situation and a highly improbable catastrophe. It was hypothesized that this type of "perseverative reasoning" would increase the subjective likelihood of the feared catastrophe. In an experiment with 63 healthy undergraduates, we tested whether OC-like perseverative reasoning induces feelings of uncertainty about a harmful outcome and makes this outcome more credible. Furthermore, we explored whether making multiple series of events increases these effects. Participants were administered a neutral situation with a catastrophic improbable outcome. In a pre- and post-test, they rated the credibility of this outcome and feelings of uncertainty about the outcome. In between, two experimental groups were instructed to generate respectively one or five series of intermediate steps between the situation and the harmful outcome, while a control group carried out a filler task. Consistent with the predictions, perseverative reasoning enhanced the credibility of a negative, improbable outcome. However, there were no differences between the two experimental conditions (one or five reasoning chains), and perseverative reasoning did not increase uncertainty about the outcome. The OC-like generation of small steps between an innocuous situation and a negative outcome increases the credibility of a feared outcome, potentially serving to maintain obsessive-compulsive disorder (OCD) problems.

Exposure plus response prevention versus exposure plus safety behaviours in reducing feelings of contamination, fear, danger and disgust. An extended replication of Rachman, Shafran, Radomsky & Zysk (2011)

BACKGROUND AND OBJECTIVES

Safety behaviours are widely held to impede the beneficial effects of exposure, certainly in OCD. Recently, Rachman, Radomsky, Shafran, and Zysk (2011) challenged this view. Healthy volunteers repeatedly touched a contaminant in two sessions. Half of the participants did not engage in safety behaviours after touching (exposure + response prevention), while the other half did (exposure + safety behaviours, i.e., cleaning hands with a hygienic wipe). Scores of contamination, fear, danger, and disgust decreased in both sessions and the effects were not impeded by safety behaviours. Three potential artefacts were identified in the Rachman et al. study: a no-treatment control group was lacking, the stop rules for ending exposure differed between conditions, and positive expectations may have been induced in the safety behaviours group. We tried to critically replicate the main findings.

METHOD

The Rachman et al. (2011) study was replicated, with 44 volunteers but stop rules and expectations were similar between treatments, and effects were also assessed in a no-intervention control group.

RESULTS

Relative to the control condition, both exposure interventions induced reliable decreases in feelings of contamination, fear, danger, and disgust. The decline followed an exponential curve with the largest gains at the first trials of each session.

LIMITATIONS

Findings were obtained from a non-clinical sample.

CONCLUSION

The findings attest to the robustness of the Rachman et al. findings, and challenge the notion that safety behaviours should be dismissed categorically in exposure treatments.

Taxing working memory reduces vividness and emotional intensity of images about the Queen's Day tragedy

Eye movements during exposure to distressing mental images reduce their vividness and emotional intensity, which may be due to both tasks competing for working memory (WM) resources. WM theory predicts an inverted U-shaped relationship between degree of taxing and beneficial effects: greater taxing of WM will more greatly reduce vividness/emotionality, but extremely taxing tasks prevent holding the image in mind, thereby reducing benefits. This study examined whether mental arithmetic (subtraction) tasks during visual imagery reduce image vividness/emotionality ratings, and taxing WM and reduced vividness/emotionality show the predicted quadratic relationship. A non-clinical sample retrieved a distressing image of the Queen's Day tragedy (which occurred 1-3 months earlier in the Netherlands), and rated it for vividness and emotionality. Participants were assigned to one of four conditions: exposure alone or exposure with concurrent 'simple' subtraction, 'intermediate' subtraction, or 'complex' subtraction. Afterwards, vividness and emotionality were rated again. A reaction time task showed that the subtraction tasks increasingly taxed WM. Consistent with WM theory, exposure with subtraction reduced image vividness and emotionality compared to exposure alone. The expected inverse U-curve relationship was found for emotionality, but not for vividness: simple or intermediate subtraction had more beneficial effects than no dual-task or complex subtraction. Clinical implications are discussed.

Evaluating the Effect of Eye Movements on Positive Memories Such as Those Used in Resource Development and Installation

Resource development and installation (RDI) is an eye movement desensitization and reprocessing (EMDR)-related procedure developed to strengthen positive associations in positive and resourceful memories (Korn & Leeds, 2002). This study tested the assumption that bilateral stimulation (horizontal eye movements [EM]) in RDI “appears to lead to spontaneous, rapid increases in affective intensity . . . and to rich, emotionally vivid associations” (Korn & Leeds, p. 1469). This study also tested whether eye movement effects could be better accounted for by working memory or by interhemispheric interaction theory. Fifty-three undergraduate students each recalled three memories of pride, perseverance, and self-confidence. They provided pretest and posttest ratings of each memory for vividness, pleasantness, and experienced strength of the positive quality, before and after performing three simultaneous tasks during recall: horizontal EM, vertical EM, and recall only. Results were fully in line with working memory predictions, with significant decreases for all variables following both eye movement tasks. There was no support for the interhemispheric hypothesis. It is concluded that the effectiveness of bilateral stimulation in RDI is questionable. Clinical implications are discussed.

Low specificity of symptoms on the post-traumatic stress disorder (PTSD) symptom scale: A comparison of individuals with PTSD, individuals with other anxiety disorders and individuals without psychopathology

OBJECTIVES

Screening for post-traumatic stress disorder (PTSD) takes place in clinical and research settings where diagnostic interviews are not feasible, and typically relies on self-report instruments like the PTSD symptom scale (PSS). Concerns have been raised about the specificity of PTSD symptoms assessed by questionnaires. This study examined whether the PSS distinguishes between patients with PTSD and those with other anxiety disorders or healthy controls.

DESIGN

A between-participants design was employed.

METHODS

The participants were 65 individuals with PTSD, 40 individuals with other anxiety disorders and 40 healthy controls. They completed the PSS with respect to a range of stressful life-events.

RESULTS

Using this instrument, 86% of individuals with PTSD and 5% of healthy controls endorsed sufficient symptoms to meet the PTSD diagnosis. This was also the case for 43% of individuals with other anxiety disorders, and self-reported symptoms related to traumatic events and aversive events that are generally not considered traumatic.

CONCLUSIONS

The findings suggest that many people screened positive for PTSD may actually be suffering from another anxiety disorder.

Autobiographical memory specificity and symptoms of complicated grief, depression, and posttraumatic stress disorder following loss

This study examined the specificity and content of autobiographical memories among bereaved individuals. Self-report measures of bereavement-related distress and a standard and trait version of the Autobiographical Memory Test (AMT) were administered to 109 bereaved people. We examined associations of memory specificity with (a) demographic and loss-related variables and with (b) symptom-levels of complicated grief (CG), depression, and posttraumatic stress disorder (PTSD), (c) associations of the content of memories (related vs. unrelated to the loss/lost person) with symptoms, and (d) the degree to which associations of symptom-levels with memory specificity and content differed between the standard and trait version of the AMT. Findings showed that (a) memory specificity varied as a function of age, education, and kinship; (b) reduced memory specificity was significantly associated with symptom-levels of CG, but not depression and PTSD; (c) symptom-levels of CG and PTSD were associated with a preferential retrieval of specific memories that were related to the loss/lost person on the standard AMT, whereas all three symptom-measures were associated with preferential retrieval of loss-related specific memories on the trait AMT; and (d) on the trait AMT, but not the standard AMT, symptom-measures remained significantly associated with a preferential retrieval of loss-related specific memories, when controlling for relevant background variables. Among other things, these results show that reduced memory specificity is associated with self-reported CG-severity but not depression and PTSD following loss. Moreover, the results are consistent with recent research findings showing that memories tied to the source of an individual's distress (e.g., loss) are immune to avoidant processes involved in the standard reduced specificity effect.