When does imagery rescripting become a double-edged sword? - Investigating the risk of memory distortion through imagery rescripting in an online Trauma film study.

Imagery Rescripting (ImRs) has proven effective in reducing involuntary emotional memories. However, it is unclear whether and when it may lead to reduced accuracy of voluntary memory. Although previous analogue studies suggest that ImRs does not pose a general risk regarding memory distortion, it can not be ruled out that ImRs could cause memory impairment under certain risk conditions. In our three-day online trauma film study we investigated in a healthy sample (N = 267) whether specific instructions during ImRs as typically provided in clinical practice (i.e., detailed imagery with a sensory focus) increase the risk of memory distortions. Additionally, we examined whether the completeness of the original memory moderates these instruction effects. Contrary to our expectations, a sensory focus during ImRs was associated with higher memory accuracy in a recognition task, independently of the quality of the original memory. These results extend previous findings by suggesting that ImRs does not even impair memory performance when the quality of the original memory is poor and when the production of sensory-rich images is specifically encouraged. Our results question current practices employed to assess witness statement credibility, which are partly based on concerns that trauma-focused interventions like ImRs undermine memory accuracy.

Effects of imagery rescripting and imaginal exposure on voluntary memory.

Trauma-focused imagery-based interventions, such as Imagery Rescripting (ImRs) and Imaginal Exposure (ImE), are effective in reducing involuntary re-experiencing in PTSD. However, it has been suggested that they may impair voluntary memory. This study investigates whether ImRs and ImE distort voluntary memory of an analogue trauma. We presented a trauma film to N = 120 healthy participants (Session 1) and randomly allocated them to one of two intervention conditions (receiving one session of ImRs or ImE) or to a no-intervention control condition (NIC) afterwards (Session 2). Voluntary memory was assessed using a free recall (Sessions 2 and 3), and a cued recall as well as a recognition task (both Sessions 3 and 4). The ImRs and ImE groups did not differ from NIC in the cued recall task and the recognition task. However, ImE (compared to ImRs and NIC) led to an increase in correct reported details in the free recall. In sum, the current findings do not suggest that ImRs or ImE impair voluntary memory.

The dilemma of trauma-focused therapy: effects of imagery rescripting on voluntary memory.

Trauma-focused imagery-based interventions are suspected to alter or even distort declarative voluntary memory of a traumatic event, especially if they involve the active modification of imagery, e.g., as used in imagery rescripting (ImRs). However, systematic research is lacking so far. To investigate whether ImRs modifies voluntary memory of a standardized autobiographical aversive event (Trier Social Stress Test) (Session 1), healthy participants (N = 100) were randomly assigned to either an intervention condition receiving one session of ImRs or to a no-intervention control condition (NIC) (Session 2). Voluntary memory was examined using a free recall (Sessions 2 and 3) and a cued recall (Sessions 3 and 4). Although voluntary memory tended to deteriorate over time, contrary to expectations, this effect was not associated with ImRs. Remarkably, the number of correct details in free recall even improved in ImRs but not in NIC. This challenges the view that ImRs alters voluntary memory.

Amelioration of cognitive control in depression by transcranial direct current stimulation.

BACKGROUND: Deficient cognitive control over emotional distraction is a central characteristic of major depressive disorder (MDD). Hypoactivation of the dorsolateral prefrontal cortex (dlPFC) has been linked with this deficit. In this study, we aimed to enhance the activity of the dlPFC in MDD patients by anodal transcranial direct current stimulation (tDCS) and thus ameliorate cognitive control. METHODS: In a double-blinded, balanced, randomized, sham-controlled crossover trial, we determined the effect of a single-session tDCS to the left dlPFC on the cognitive control in 22 MDD patients and 22 healthy control subjects. To assess the cognitive control, we used a delayed response working memory task with pictures of varying content (emotional vs. neutral) presented during the delay period. RESULTS: Emotional pictures presented during the delay period impaired accuracy and response time of patients with MDD, indicating an attentional bias for emotional stimuli. Anodal tDCS to the dlPFC was associated with an enhanced working memory performance both in patients and control subjects. Specifically in subjects with MDD, the attentional bias was completely abolished by anodal tDCS. CONCLUSIONS: The present study demonstrates that anodal tDCS applied to the left dlPFC improves deficient cognitive control in MDD. Based on these data, tDCS might be suitable to support the effects of behavioral training to enhance cognitive control in MDD.