EMDR: A putative neurobiological mechanism of action

Abstract

Numerous studies have provided evidence for the efficacy of eye movement desensitization and reprocessing therapy (EMDR) in the treatment of posttraumatic stress disorder (PTSD), including recent studies showing it to be more efficient than therapist-directed flooding. But few theoretical explanations of how EMDR might work have been offered. Shapiro, in her original description of EMDR, proposed that its directed eye movements mimic the saccades of rapid eye movement sleep (REM), but provided no clear explanation of how such mimicry might lead to clinical improvement. We now revisit her original proposal and present a complete model for how EMDR could lead to specific improvement in PTSD and related conditions. We propose that the repetitive redirecting of attention in EMDR induces a neurobiological state, similar to that of REM sleep, which is optimally configured to support the cortical integration of traumatic memories into general semantic networks. We suggest that this integration can then lead to a reduction in the strength of hippocampally mediated episodic memories of the traumatic event as well as the memories' associated, amygdala-dependent, negative affect. Experimental data in support of this model are reviewed and possible tests of the model are suggested.

The efficacy and psychophysiological correlates of dual-attention tasks in eye movement desensitization and reprocessing (EMDR)

“…Sack et al (2008) argued that the physiological correlates of the EMs were a result of a biphasic reaction in which an OR was first dominant but during ongoing exposure a stress-related psychophysiological response emerged. Based is a complex state without a well defined autonomic profile, and patients are awake in EMDR, thus it cannot be expected that physiological responses in EMDR be identical to those seen in REM-sleep (Stickgold, 2002). In our data, the increase in RR may represent the presence of an induced state similar to REM-sleep.…”

Posttraumatic nightmares and psychopathology in children after road traffic accidents

“…However, a detailed examination of the worst dreams experienced by 13 teenage girls following severe sexual abuse showed a different picture (Garfield, 1987). In this sample, dreams contained no explicit replications but only symbolic references to the traumatic experiences.Several theories propose that posttraumatic nightmares are related to the central pathological mechanism of posttraumatic stress disorder (Kramer, Schoen, & Kinney, 1984;Schreuder, 1995;Stickgold, 2002). For instance, Stickgold (2002) In the first assessment (10 days after the accident) the number of nightmares (introduced as "frightening dreams") since the accident was examined.…”

“…Several theories propose that posttraumatic nightmares are related to the central pathological mechanism of posttraumatic stress disorder (Kramer, Schoen, & Kinney, 1984;Schreuder, 1995;Stickgold, 2002). For instance, Stickgold (2002) In the first assessment (10 days after the accident) the number of nightmares (introduced as "frightening dreams") since the accident was examined.…”

“…For instance, Stickgold (2002) considers replicative posttraumatic nightmares as a psychological correlate of changes in normal brain function during REM sleep due to posttraumatic stress. This assumption is in line with the finding that exact replicative content seems to appear exclusively in posttraumatic dreams (Fosse, Fosse, Hobson, & Stickgold, 2003).…”

Neurobiology and Stochastic Resonance: Going Deeper

“…It is postulated that a related surge in acetylcholine (a neurotransmitter) is created as a consequence of DAS/BLS, which can then facilitate rapid eye movement (REM)-like physiological systems. This REM-like state is proposed to be capable of decreasing the strength of hippocampally mediated episodic memories and amygdaloid-mediated negative affect, which we see in PTSD (Stickgold, 2002). Sleep researchers at Harvard Medical School explored this area of overlap.…”