Within EMDR, the speed, rhythm, and modality of bilateral stimulation (BLS) are adjusted in response to the client’s presentation and therapeutic aims (Shapiro, 2018). In clinical practice, slower forms of bilateral stimulation may be used within preparation-phase interventions to support stabilisation, including containment, affect regulation, and the strengthening of adaptive associations (Parnell, 2013).
This distinction is clinically important. Slower bilateral stimulation is generally used with the intention of supporting regulation and resourcing, rather than activating traumatic memory networks for reprocessing. EMDR literature consistently emphasises the importance of adapting bilateral stimulation parameters according to therapeutic need (Shapiro, 2018).
Some authors have also highlighted the broader application of modified bilateral stimulation within complex presentations. For example, Hase (2021) discusses flexibility in the use of bilateral stimulation across different phases of therapy. In addition, approaches such as Constant Installation of Present Orientation and Safety (CIPOS) utilise slower, carefully titrated bilateral stimulation to maintain present orientation and safety, sitting at the interface between stabilisation and trauma processing in EMDR (Knipe, 2018).
It is important to note that the empirical evidence base specifically examining slow bilateral stimulation in isolation remains limited (you can read a fuller discussion of the evidence here). The following discussion therefore reflects current clinical practice, theoretical understanding, and practice-informed application within trauma-focused work.
When Slow Bilateral Auditory Stimulation May Be Helpful
Slow bilateral auditory stimulation may be helpful in several clinical contexts, particularly where the aim is to support regulation and stabilisation.
It may be used to:
- support nervous system regulation when clients present with overwhelm or heightened stress
- provide a grounding anchor between sessions, particularly where clients notice a return of anxiety after initial therapeutic gains in session
- enhance resourcing work, supporting the development and strengthening of internal stabilisation strategies such as peaceful place
- support preparation for trauma processing in EMDR, including strengthening associations between positive affect and adaptive beliefs about the self
- support a reduction in general anxiety, both within sessions and between sessions
Important Clinical Boundaries
Slow bilateral auditory stimulation should be used within clear clinical boundaries and with appropriate clinical formulation. It is important to emphasise that:
- it is not intended for trauma processing/reprocessing outside of therapy sessions
- it should be used as an adjunct to therapy, not a replacement for it
- pacing is essential, with careful attention to the client’s window of tolerance (Siegel, 1999)
- therapist guidance is often needed, particularly where clients are developing regulation skills for the first time
In addition, clinicians should remain mindful that:
- slow BLS may not be appropriate in the presence of significant dissociative instability without adequate containment strategies
- clients should be supported to maintain dual awareness when using any form of bilateral stimulation
Situations Requiring Caution
Clinical judgement is particularly important in the following contexts:
- Dissociation – refers to experiences of disconnection, whereas structural dissociation describes how this disconnection may be organised into distinct parts of the personality following trauma (van der Hart et al., 2006). Use outside of sessions may not be appropriate initially until stabilisation has been established.
- Autonomic instability – for some individuals, states of calm may feel unfamiliar or unsafe. Shifts towards relaxation may increase anxiety and should be approached gradually
- Chronic hyperarousal or performance anxiety – clients who feel pressure to “get it right” may experience increased distress when engaging with structured exercises outside of sessions
- Pregnancy and specific clinical presentations – while trauma-focused therapies such as EMDR and CBT have not been shown to be harmful in pregnancy, clinical judgement should guide the use of any adjunctive tools
When It Should Not Be Used
Slow bilateral auditory stimulation should not be used:
- in the presence of acute dissociative destabilisation
- where clients are unable to maintain dual awareness
- as a means of engaging with traumatic material outside of therapy sessions
Clinical Implications
Slow bilateral auditory stimulation is best understood as a supportive, stabilisation-focused tool within trauma-informed therapy. It may contribute to regulation, grounding, and resourcing when used appropriately, but it does not replace the need for careful formulation, pacing, and therapeutic presence. Use should be guided by the clinician’s formulation, including assessment of stability, dissociation, and readiness for resourcing work. This is particularly relevant in early-phase trauma work, where maintaining stability and dual awareness is essential.
Audio Resources for Clinical Practice
In practice, many clients struggle most with maintaining regulation between sessions—particularly following difficult or activating work.
To support this phase of therapy, I’ve developed clinician-designed bilateral audio resources for stabilisation and nervous system regulation between sessions.
• Explore the full audio library → Willow Tree Wellbeing Audio Library
• Or try a short stabilisation audio → Access a Free Stabilisation Audio Sample
About the Author
Donna Dickinson is a BABCP-accredited CBT therapist and EMDR-trained psychotherapist with over 19 years of NHS experience in trauma-focused work. Her clinical interests include nervous system regulation and stabilisation in therapy. She develops clinically informed audio resources to support stabilisation and regulation within EMDR-informed practice.
References
Hase, M. (2021). The use of slow bilateral stimulation in EMDR therapy: A review of clinical practice and emerging perspectives. Frontiers in Psychology, 12, 742. https://doi.org/10.3389/fpsyg.2021.742
Knipe, J. (2018). EMDR Toolbox: Theory and Treatment of Complex PTSD and Dissociation. New York: Springer Publishing.
Shapiro, F. (2018). Eye Movement Desensitization and Reprocessing (EMDR) Therapy: Basic Principles, Protocols, and Procedures (3rd ed.). New York: Guilford Press.
Parnell, L. (2013). Attachment-Focused EMDR: Healing Relational Trauma. New York: W. W. Norton & Company.
Siegel, D. J. (1999). The Developing Mind: How Relationships and the Brain Interact to Shape Who We Are. New York: Guilford Press.
van der Hart, O., Nijenhuis, E. R. S., & Steele, K. (2006). The Haunted Self: Structural Dissociation and the Treatment of Chronic Traumatization. New York: W. W. Norton & Company.