Praxis Blog

Using the Flash Technique to Support EMDR Treatment

EMDR, EMDR training, EMDR blog, therapy, trauma blog

Author: Philip Manfield, PhD

The flash technique (FT) was introduced in 2017 (Manfield et al.) to solve the problem of how to help clients tolerate disturbing memories that they find overwhelming. 

Most trauma treatment approaches require clients to think about their traumatic memories as a prerequisite to resolving them, but our most difficult clients are either unable or unwilling to focus on memories so severe as to be destabilizing. 

Originally the flash technique started as a form of extreme titration, slicing and dicing the trauma memory so finely that the client would be able to address even the most painful memories one little piece at a time. But, when clients were instructed to address the memory so rapidly and peripherally that no disturbance was felt, dramatic processing effects were observed. As the flash technique evolved, client’s conscious exposure to the memory was eventually restricted to an initial brief discussion of it, and a periodic check-in to see if anything about the memory was changing. During most of the process clients are asked to think of a positive engaging focus (PEF) to help prevent them from thinking about the disturbing memory.

Although not the original inspiration for the technique, the research of Paul Siegel, et al., (2011, 2017) has suggested a possible way of understanding the mechanism of action of the flash technique. Siegel and his associates published a series of studies examining the impact of “non-reportable” exposure. They recruited subjects with spider phobias and exposed half of them to a clearly visible image of a tarantula. The other half saw the same image flashed on a screen so briefly that they did not know they had seen a tarantula. The phobias of both groups were reduced by their exposure to the tarantula, but, surprisingly, the group with the non-reportable exposure benefited significantly and maintained those benefits at one year follow-up. One of Siegel’s studies involved the use of fMRI images to understand the reason for this outcome. The fMRI showed that two parts of the brain instrumental in the processing of fear, the ventral medial prefrontal cortex and the dorsal lateral prefrontal cortex, became relatively inactive when the subject was reacting to the fearful stimulus of the tarantula image, but were extremely active when the subject was unaware of having been exposed to a fearful stimulus.

It is very possible that FT utilizes a similar mechanism. By preventing clients from focusing on their disturbing memories, FT prevents the client from going into a traumatized state in which important parts of the brain necessary for resolving the memories are relatively unavailable.  The results have been startling. Earlier this year a study was published in which FT was used effectively with highly dissociative subjects in a group setting in a homeless shelter (Wong, 2019). Most recently, a research paper submitted for publication in June, 2019 reported the results of four almost identical studies involving totally 813 flash “sessions” of less than 15 minutes in duration conducted in a group format in which participants were given instructions that assisted them in performing the technique on themselves. Two of these studies were conducted in the United States, one in Australia, and one in Uganda. In the two U.S. studies, the mean disturbance level, measured on an 11 point 0 to 10 subjective units of disturbance scale (SUDS; Wolpe, 1958) where 0 represented “no disturbance at all” and 10 represented “the worst the subject could imagine,” was reduced by over two thirds. In the other two studies, the reduction was over 80%. In all four studies, the results were highly significant (p<.001) and effect sizes were large. In all four studies mean benefits of FT were sustained or improved at four week follow-up. Moreover this technique has been shown to be extremely safe. In the four studies reported, only two sessions out of 813 reflected an increase, however slight, in SUDS. Both of these subjects then did a second session in which disturbance was reduced. 

In less than two years since FT was introduced, over 4000 therapists have been trained in this technique, and a lively listserv with over 1000 members has developed. As new ideas emerge for executing the technique more effectively, results continue to gradually improve.

See also: How EDMR Can Work for You: Adapt to the Needs of Your Client

To date, FT has been used exclusively in the preparation phase of Eye Movement Desensitization and Reprocessing (EMDR). With FT, clients’ readiness to process memories which would otherwise cause them to dissociate or defend, is substantially increased, allowing some trauma memories to be “targeted” that would normally require extensive preparation before being treated. It is hoped that the role that FT plays in the preparation phase of EMDR, however, is equally suited for prolonged exposure, cognitive behavioral therapy, and virtually all treatments of trauma. 

Learn How Using the Flash Technique Can Transform the Lives of Your Clients!


Manfield, P., Lovett, J., Engel, L., & Manfield, D. (2017). Use of the flash technique in EMDR therapy: Four case examples. Journal of EMDR Practice and Research, 11(4), 195–205.

Siegel, P., Anderson, J. F., & Han, E. (2011). Very brief exposure II: The effects of unreportable stimuli on phobic behavior. Consciousness and Cognition, 20(2),181–190.

Siegel, P., Warren, R., Wang, Z., Yang, J., Cohen, D., Anderson, J. F., … Peterson, B. S. (2017). Less is more: Neural activity during very brief and clearly visible exposure to phobic stimuli. Human Brain Mapping, 38(5), 2466–2481.

Wolpe, J. (1958). Psychotherapy by reciprocal inhibition. Stanford, CA: Stanford University Press.

Wong, Sik-Lam. (2019). Flash technique group protocol for highly dissociative clients in a homeless shelter: A clinical report. Journal of EMDR Practice and Research, 13(1), 20–31.