NCT06878807

Exploring the Role of Working Memory Saturation in Eye Movement Desensitization and Reprocessing (EMDR) Using the Eye Blink Conditioning Paradigm

Completed NA Last updated 16 September 2025

What this trial tests

NA trial testing eye movement in Eye Movement Desensitization and Reprocessing in 112 participants. Completed in 1 April 2025.

Timeline

1 April 2022

Primary endpoint
1 December 2024

1 April 2025

Quick facts

Lead sponsor	Hospital Clinic of Barcelona
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	single
Primary purpose	treatment
Enrollment	112
Start date	1 April 2022
Primary completion	1 December 2024
Estimated completion	1 April 2025
Sites	1 location across Spain

Drugs / interventions tested

• eye movement
• TMT-B

Conditions studied

• Eye Movement Desensitization and Reprocessing — all drugs for Eye Movement Desensitization and Reprocessing →

Sponsor

Hospital Clinic of Barcelona

Who can join

Adults 18 to 65, any sex, with Eye Movement Desensitization and Reprocessing. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Eye Movement Desensitization and Reprocessing (EMDR) is a well-established, evidence-based treatment for posttraumatic stress disorder (PTSD). It is endorsed by leading organizations such as the American Psychiatric Association and the World Health Organization. During EMDR therapy, patients focus on recalling traumatic events while simultaneously engaging with an external stimulus. Specifically, patients undergo lateral eye movements. This process is believed to reduce the vividness and emotional intensity of traumatic memories by addressing and desensitizing their cognitive, emotional, and physical components. Despite its proven efficacy in treating PTSD, the precise mechanisms underlying these therapeutic effects remain not fully understood.

Several hypotheses have been proposed to explain the efficacy of EMDR. Among them, the working memory hypothesis is particularly influential and is supported by a substantial body of research. This hypothesis suggests that aversive memories and fear, when recalled, occupy limited memory resources. Therefore, performing a task, such as eye movements, during the recall of the traumatic experience would result in a competition for limited memory resources, leading to a decrease in the vividness and emotional intensity of the traumatic memory. Consequently, the dual task inherent in EMDR is thought to facilitate a rapid elimination of the emotional responses triggered by the traumatic memory, allowing patients to alleviate the physical and psychological distress associated with the trauma.

Measuring the effects of an EM intervention through a standardized protocol could clarify the conditions under which the intervention is most effective and elucidate the potential mechanisms of EMDR. In this context, the Eye Blink Conditioning (EBC) task, a well-established and standardized conditioning paradigm, seems relevant for testing the working memory hypothesis.

In the EBC task, eyelid closure is measured in response to a corneal air puff, which acts as the unconditioned stimulus. The unconditioned stimulus is paired with a neutral stimulus, a tone, which becomes a conditioned stimulus by eliciting a conditioned response similar to that produced by the unconditioned stimulus. After the conditioning phase, participants undergo the extinction phase. In this phase, the conditioned stimulus is presented without the unconditioned stimulus for many trials, and the main objective is to measure how many trials it takes for the participants to eliminate the previous associative learning between the aversive stimulus (air puff) and the conditioned stimulus (tone).

This study aimed to explore whether the effectiveness of a straightforward eye movement intervention in accelerating extinction is influenced by the working memory hypothesis. The hypothesis is that the enhancement of extinction learning is dependent on working memory saturation. Understanding the role of working memory saturation in the effectiveness of eye movements during extinction learning could provide critical insights into the working memory hypothesis as a potential key mechanism underlying the efficacy of EMDR therapy.

Publications & conference data

No peer-reviewed publications indexed yet for this trial. Completed trials usually publish results within 12-18 months.