Eye movement desensitization and reprocessing

Eye movement desensitization and reprocessing (EMDR) is a form of psychotherapy that is a recommended treatment for post-traumatic stress disorder, but remains controversial within the psychological community. It was devised by Francine Shapiro in 1987 and originally designed to alleviate the distress associated with traumatic memories such as post-traumatic stress disorder (PTSD).

EMDR involves focusing on traumatic memories in a manner similar to exposure therapy while engaging in side-to-side eye movements or other forms of bilateral stimulation. It is also used for some other psychological conditions.

EMDR is recommended for the treatment of PTSD by various government and medical bodies citing varying levels of evidence, including the World Health Organization, the UK National Institute for Health and Care Excellence, the Australian National Health and Medical Research Council, and the US Departments of Veteran Affairs and Defense. The US National Institute of Medicine found insufficient evidence to recommend EMDR. The American Psychological Association suggests EMDR may be useful for treating adult PTSD. Treatment guidelines note EMDR effectiveness is statistically the same as trauma-focused behavioral therapy, and the Australian National Health and Medical Research Council notes that this may be due to including most of the core elements of cognitive behavioral therapy (CBT).

There is debate about how the therapy works and whether it is more effective than other established treatments. The eye movements have been criticized as having no scientific basis. The founder promoted the therapy for the treatment of PTSD, and proponents employed untestable hypotheses to explain negative results in controlled studies. EMDR has been characterized as a pseudoscientific purple hat therapy (i.e., only as effective as its underlying therapeutic methods without any contribution from its distinctive add-ons).

Classification and technique
EMDR adds a number of non-scientific practices to exposure therapy. EMDR is classified as one of the "power therapies" alongside thought field therapy, Emotional Freedom Techniques and others – so called because these therapies are marketed as being superior to established therapies which preceded them.

EMDR is typically undertaken in a series of sessions with a trained therapist. The number of sessions can vary depending on the progress made. A typical EMDR therapy session lasts from 60 to 90 minutes.

Trauma and PTSD
The person being treated is asked to recall an image, phrase, and emotion that represent a level of distress related to a trigger while generating one of several types of bilateral sensory input, such as side-to-side eye movements or hand tapping. The 2013 World Health Organization practice guideline says that "Like cognitive behavioral therapy (CBT) with a trauma focus, EMDR aims to reduce subjective distress and strengthen adaptive beliefs related to the traumatic event. Unlike CBT with a trauma focus, EMDR does not involve (a) detailed descriptions of the event, (b) direct challenging of beliefs, (c) extended exposure or (d) homework."

Training
Shapiro was criticized for repeatedly increasing the length and expense of training and certification, allegedly in response to the results of controlled trials that cast doubt on EMDR's efficacy. This included requiring the completion of an EMDR training program in order to be qualified to administer EMDR properly after researchers using the initial written instructions found no difference between no-eye-movement control groups and EMDR-as-written experimental groups. Further changes in training requirements and/or the definition of EMDR included requiring level II training when researchers with level I training still found no difference between eye-movement experimental groups and no-eye-movement controls and deeming "alternate forms of bilateral stimulation" (such as finger-tapping) as variants of EMDR by the time a study found no difference between EMDR and a finger-tapping control group. Such changes in definition and training for EMDR have been described as "ad hoc moves [made] when confronted by embarrassing data".

Medical uses
EMDR is controversial within the psychological community. It is used by some practitioners for trauma therapy and in the treatment of complex post-traumatic stress disorder.

Effectiveness
A Cochrane systematic review comparing EMDR with other psychotherapies in the treatment of Chronic PTSD found EMDR to be just as effective as TF-CBT and more effective than the other non-TF-CBT psychotherapies. Caution was urged interpreting the results due to low numbers in included studies, risk of researcher bias, high drop-out rates, and overall "very low" quality of evidence for the comparisons with other psychotherapies. A 2016 systematic review and meta-analysis found that the effect size of EMDR for PTSD is comparable to other evidence-based treatments, but that the strength of evidence was of a low quality, indicating that the effect sizes achieved are associated with substantial uncertainty. A 2018 systematic review found moderate strength of evidence supporting the effectiveness of EMDR in reducing symptoms of PTSD and depression, as well as increasing the likelihood of patients losing their PTSD diagnosis.

Many randomized trials of EMDR have been criticized for poor control groups, small sample sizes, and other methodological flaws. It has been called a purple hat therapy because any effectiveness is provided by the underlying therapy (or the standard treatment), not from EMDR's distinctive features.

There is some evidence that EMDR can be as effective as trauma focused cognitive behavioral therapy (TF-CBT) for treating PTSD, though concerns have been raised about the poor quality of the underlying studies. In a 2021 systematic review of 13 studies, clients had mixed perceptions of the effectiveness of EMDR therapy.

Medical guidelines

 * The World Health Organization's 2013 report on stress-related conditions found insufficient evidence to support EMDR for acute symptoms of traumatic stress. Its 2023 guideline for mental, neurological and substance use disorders recommended EMDR with moderate evidence for adults and children in treating PTSD.
 * The 2018 International Society for Traumatic Stress Studies practice guidelines "strongly recommend" EMDR as an effective treatment for post-traumatic stress symptoms.
 * As of 2017, the American Psychological Association "conditionally recommends" EMDR for the treatment of PTSD in adults, meaning its use is suggested rather than recommended.
 * The UK National Institute for Health and Care Excellence's 2018 PTSD guidelines found low-to-very-low evidence of efficacy for EMDR in treating PTSD, but what was available justified recommending it for non combat-related trauma.
 * A 2017 joint report from the US Departments of Veterans Affairs and Defense describes the evidence for EMDR in the treatment of PTSD as "strong."
 * The Australian 2013 National Health and Medical Research Council guidelines recommends EMDR for the treatment of PTSD in adults with its highest grade of evidence, noting that "EMDR now includes most of the core elements of standard trauma-focussed CBT (TF-CBT)" and "the two variants of trauma-focussed therapy are not statistically different."
 * The Institute of Medicine's 2008 report on the treatment of PTSD found insufficient evidence to recommend EMDR, and criticized many of the available studies for methodological flaws including allegiance bias and insufficient controls.
 * The Dutch National Steering Committee on Mental Health Care has released multidisciplinary guidelines which describe "insufficient scientific evidence" to support EMDR in the acute period following a stressful event (2008), but recommend EMDR's use in chronic PTSD (2003).

Other conditions
EMDR has been tested on a variety of other mental health conditions with mixed results.
 * A 2021 systematic review and meta-analysis found EMDR to have a moderate benefit in treating depression, but the number and quality of the studies were low.
 * Positive effects have also been shown for certain anxiety disorders, but the number of studies was low and the risk of bias high. The American Psychological Association describes EMDR as "ineffective" for the treatment of panic disorder.
 * EMDR has been found to cause strong effects on dissociative identity disorder patients, leading to recommendations for adjusted use.
 * A 2023 systematic review of evidence found EMDR's effectiveness in treating mental health conditions of children and adolescents who have been sexually abused is limited.

Incomplete processing of experiences in trauma
Many proposals of EMDR efficacy share an assumption that, as Shapiro posited, when a traumatic or very negative event occurs, information processing of the experience in memory may be incomplete. The trauma causes a disruption of normal adaptive information processing, which results in unprocessed information being dysfunctionally held in memory networks. According to the 2013 World Health Organization practice guideline: "This therapy [EMDR] is based on the idea that negative thoughts, feelings and behaviours are the result of unprocessed memories." This proposed mechanism has no known scientific basis.

Other mechanisms
Several other possible mechanisms have been proposed:
 * EMDR may impact working memory. If a patient performs bilateral stimulation task while remembering the trauma, the amount of information they can recall is thought to be reduced, making the resulting negative emotions less intense and more bearable. This is seen by some as a "distancing effect". The client is then believed to re-evaluate the trauma and process it in a less-harmful environment. This explanation is plausible, given research showing that memories are more modifiable once recalled.
 * Horizontal eye movement is thought to trigger an "orienting response" in the brain, used in scanning the environment for threats and opportunities.
 * The idea that eye movement prompts communication between the two sides of the brain. This idea is not grounded in accepted neuroscience.

Bilateral stimulation, including eye movement
Bilateral stimulation is a generalization of the left and right repetitive eye movement technique first used by Shapiro. Alternative stimuli include auditory stimuli that alternate between left and right speakers or headphones and physical stimuli such as tapping of the therapist's hands or tapping devices.

Most meta-analyses have found that the inclusion of bilateral eye-movements within EMDR makes little or no difference to its effect. Meta-analyses have also described a high risk of allegiance bias in EMDR studies. One 2013 meta-analysis with fewer exclusion criteria found a moderate effect.

Pseudoscience
EMDR has been characterized as pseudoscience, because the underlying theory and primary therapeutic mechanism are unfalsifiable and non-scientific. EMDR's founder and other practitioners have used untestable hypotheses to explain studies which show no effect. The results of the therapy are non-specific, especially if directed eye movements are irrelevant to the results. When these movements are removed, what remains is a broadly therapeutic interaction and deceptive marketing. According to Yale neurologist Steven Novella:

"[T]he false specificity of these treatments is a massive clinical distraction. Time and effort are wasted clinically in studying, perfecting, and using these methods, rather than focusing on the components of the interaction that actually work."

EMDR has been characterised as a modern-day mesmerism, as the therapies have striking resemblances, from the sole inventor who devises the system while out walking, to the large business empire built on exaggerated claims. In the case of EMDR, these have included the suggestions that EMDR could drain violence from society and be useful in treating cancer and HIV/AIDS. Psychology historian Luis Cordón has compared the popularity of EMDR to that of other cult-like pseudosciences, facilitated communication and thought field therapy.

A parody website advertising "sudotherapy" created by a fictional "Fatima Shekel" appeared on the internet in the 1990s. Proponents of EMDR described the website as libelous, since the website contained an image of a pair of shifting eyes following a cat named "Sudo", and "Fatima Shekel" has the same initials as EMDR's founder, Francine Shapiro. However, no legal action took place against the website or its founders, who are likely protected by American First Amendment protections.

History
EMDR was invented by Francine Shapiro in 1987.

Fuelled by marketing hype, EMDR was taken up enthusiastically by therapists even while scientists remained skeptical. By 2012 more than 60,000 therapists had been trained in its use.

Society and culture

 * Sandra Bullock used EMDR following a home invasion by a stalker in 2014.
 * In 2019 Jameela Jamil said she partook in EMDR therapy to treat her post traumatic stress disorder.
 * In 2021 Prince Harry took a course of EMDR and filmed a session for Oprah Winfrey during a mental health television documentary.
 * In 2022 BBC war correspondent Fergal Keane, who suffered from PTSD, credited his EMDR therapist with helping save his life.