The first question I get when I talk about EMDR Therapy at a party is, “How does it work?” I must confess this topic always seemed above my pay grade, but recently I took a look at some of the answers to the question as I prepare to deliver Basic EMDR training to a group of new therapists. Here for your reading enjoyment are a number of theoretical possibilities about how EMDR Therapy might work. None of these possibilities has been proven. And remember, it took 40 years to figure out exactly how penicillin works too.
- Francine Shapiro, the creator of EMDR Therapy, at first thought something like Rapid Eye Movement sleep was at work. Our eyes refocus left to right during sleep, making it look like they are moving beneath our eyelids. She thought the fact that muscles in the eye relax during REM sleep, and the fact that EMDR seemed to mimic REM sleep, might mean that a relaxation response was being induced during the therapy. Inducing that response paired with trauma memory retrieval, she thought, might account for the resolution of trauma memories. Other researchers pursued this idea and suggested that various REM-like neurobiological mechanisms could facilitate activation of episodic memories and the integration of those memories into cortical semantic memory. But this explanation doesn’t account for how tones and tapping seem to work, judging from clinical practice, in addition to eye movements during EMDR Therapy.
- Another thesis suggests that the part of the brain that performs working memory (i.e. our cognitive system with limited capacity responsible for temporarily holding information available for processing, like memory in a personal computer) gets overtaxed in EMDR Therapy. Pairing inner attention to the target memory and external attention to the bilateral eye movements has the effect of disrupting working memory, impairing the target visual memory, and reducing the vividness and emotionality of the traumatic memory.
- The Orienting Response theory is another possible explanation of how EMDR Therapy works. The orienting response is something we all have that occurs when our attention is drawn to something of interest, a new stimulus. The theory goes that since the orienting response in EMDR Therapy is elicited by the alternating eye movements or tones at a time when there is no real danger, the ordinarily alarming reflex is then followed by relaxation. This makes it possible for the person to access and process traumatic memories without avoidance.
- One intriguing theory comes from Ulrich Lanius and Uri Bergmann in Ulrich F. Lanius, Sandra L. Paulsen, and Frank M. Corrigan,Neurobiology and Treatment of Traumatic Dissociation: Toward an Embodied Self (2014). They propose that the sensory stimulation and sensory awareness built into EMDR (Eye movements, tapping, and sound tones) directly affect activity of the part of the limbic brain known as the thalamus. The thalamus consists of 50 groupings of nerve cells, neural tissue, and fibers in the limbic brain. It is the main source for the external stimulation of the cortex, i.e. it is the sensory gateway to the cortex. Lanius and Bergman note that the thalamus acts as a relay station mediating processing from the top down, i.e. information from the cortex, and from the bottom-up, i.e. information from the brainstem. And they note the thalamus plays a key role in the integration of information across the three main parts of the brain. Lanius and Bergman suggest that the sensory stimulation and sensory awareness of EMDR Therapy affect thalamic activity, thus enabling the passing of previously dissociated, unprocessed memory material to the cortex for processing and formation of narrative memory.
- Shapiro in her 2017 book, Eye Movement Desensitization and Reprocessing [EMDR] Therapy, Third Edition, notes these other factors of healing, which while not detailed neurobiological explanations, are important too:
- Small amounts of exposure to a past traumatic memory, carefully managed, have long been proven to facilitate healing from trauma
- The perceived mastery of repeatedly evoking and dismissing a memory improves self-efficacy
- Attending to somatic experience in the EMDR Therapy protocol creates an awareness of the changeability of experience. It creates some distance from the experience and so also increases self-awareness and self-efficacy.
- The cognitive reframing implicit in naming the negative cognition allows for an awareness of the impact of a memory and the irrationality of some beliefs
- By asking specific questions about the memory, the person is helped in reconnecting behavior, affect, sensation, and knowledge about an event.
- Free association elicited by the repeated question “What’s coming up now” gives access to aspects of experience not yet fully in consciousness and allows for possible integration
- The mindfulness instruction “Just notice” after each set helps counteract the fear of inner experience by encouraging people to notice their experience
Stay tuned as the search goes on to understand what effective mechanisms of EMDR Therapy are at work as we “Go with that” and “Just notice.”