Mechanisms of EMDR and Bilateral Stimulation

Eye Movement Desensitisation and Reprocessing (EMDR) with bilateral stimulation is a revolutionary therapeutic approach that has gained widespread recognition for its remarkable efficacy in treating trauma and various mental health disorders. The treatment involves several key elements, including specified target identification, bilateral stimulation, and installation of positive beliefs.

Bilateral stimulation, a cornerstone of EMDR, is achieved through rhythmic activation of both hemispheres of the brain. We use eye movements, tapping, or auditory tones to facilitate this process. The mechanisms underlying EMDR with bilateral stimulation have been subject to various theories, below are the most evidence based hypotheses.

1. Working Memory Theory: The working memory theory suggests that bilateral stimulation disrupts the normal cognitive processing of traumatic memories by taxing the working memory. As a result, the distressing emotional charge associated with the memories is reduced. The rhythmic bilateral stimulation helps the brain to reprocess these memories in a way that is less emotionally charged and more adaptive.

2. Orienting Response Theory: The orienting response theory posits that the rhythmic bilateral stimulation used in EMDR captures the individual's attention and directs it externally. This orienting response helps to divert the focus away from distressing memories, reducing the emotional charge associated with them. By drawing attention to the external stimulus, the orienting response theory complements the dual attention mechanism in EMDR, aiding in the reprocessing of traumatic memories.

3. Neurobiological Changes: Studies indicate that bilateral stimulation activates specific brain regions involved in emotional processing and memory consolidation. The rhythmic sensory input triggers neurobiological changes, facilitating the integration of traumatic memories into a broader cognitive framework. This process enables the brain to create new associations, leading to adaptive responses and reduced emotional distress.
   

4. REM Sleep Theory: EMDR with bilateral stimulation has been likened to the eye movements that occur during Rapid Eye Movement (REM) sleep, a phase associated with dreaming and memory consolidation. It is suggested that bilateral stimulation may activate similar brain processes, facilitating the reprocessing and integration of traumatic memories during wakeful states. This phenomenon aids in reducing the emotional intensity of distressing memories and promotes adaptive responses.

5. Mindfulness: One of the key components of EMDR with bilateral stimulation is the incorporation of one's ability to remain present and mindful. During the processing sessions, clients are encouraged to stay grounded in the present moment while simultaneously engaging with distressing memories. This ability to hold one foot in the present and another in the memory helps clients develop a sense of safety and control during the therapeutic process. This ability promotes self-awareness, emotional regulation, and non-judgmental observation of thoughts and sensations, which are essential for the successful reprocessing of traumatic memories.

While research into the mechanisms of bilateral stimulation is still emerging, its effectiveness in treating trauma and mental health disorders is well-established. As our understanding continues to evolve, further insights into these mechanisms will enhance our therapeutic approach and technique. It is likely that the effectiveness of bilateral stimulation stems from a combination of these theories, suggesting how much is unknown about the complexities of our neurobiology.

Katerina Nemcova

Clinical Psychologist