Bilateral Stimulation (BLS)
Grounding Tool
An evidence-informed resource for nervous system calming and self-regulation. Not EMDR therapy. Designed for between-session grounding, anxiety relief, and daily stress management.
Please read this page before using the tool. It contains important information about what this tool is, who it is appropriate for, and when not to use it.
What is bilateral stimulation?
Bilateral stimulation (BLS) refers to rhythmic sensory input that alternates between the left and right sides of the body or visual field. That alternating rhythm activates both hemispheres of the brain in sequence and has a measurable calming effect on emotional arousal.
Bilateral stimulation is used in EMDR and other trauma-focused therapies, and has a well-supported role for nervous system calming outside of clinical settings. Research published in Frontiers in Psychology found that BLS produced significant reductions in fear expectation and physiological arousal. A 2025 fMRI study validated self-administered BLS, showing real-time quieting of the amygdala and hippocampus, and reactivation of the medial prefrontal cortex, the brain's primary emotional regulation center.
What the evidence supports
Reducing physiological arousal · Calming the amygdala (the brain's fear center) · Supporting emotional regulation between therapy sessions · Pre-event and post-session nervous system settling · General anxiety relief and daily stress management
What BLS in this context is not
EMDR therapy · Trauma processing · Treatment for any diagnosable condition · A replacement for professional care
Before you use this tool
This tool is not psychotherapy, EMDR therapy, medical advice, diagnosis, or treatment, and it is not a substitute for care from a licensed mental health or medical professional.
Do not use this tool to intentionally process traumatic memories. BLS during trauma processing should only occur within the full EMDR protocol under the direct supervision of a trained therapist. Using this tool to deliberately revisit traumatic material without a therapist present carries real risk of destabilization.
If you experience dizziness, disorientation, overwhelm, nausea, flashbacks, dissociation, or increased distress while using this tool, stop immediately, use a grounding technique you already know, and contact your therapist.
Using this tool does not create a therapist-client relationship with Walk of Life Counseling or Jason Fairweather, LPC, CSAC, ICS.
This tool is not appropriate for crisis situations. If you are in crisis, call or text 988 (Suicide and Crisis Lifeline) or contact emergency services (911).
Do not use this tool while driving, operating machinery, or doing anything that requires your full attention. The moving visual stimulus is intended for use in a safe, stationary environment only.
This tool includes a moving light bar (Phaser mode) and an optional RGB color-cycling mode that produce rhythmic, alternating visual patterns. Individuals with photosensitive epilepsy, seizure disorders, or sensitivity to alternating or flashing visual patterns should consult their physician before use.
If you experience dizziness, visual discomfort, nausea, or any unusual sensations, stop immediately. The RGB mode can be disabled using the RGB toggle in the tool.
The bilateral audio offers four sound options: soft click, river, bird call, and singing bowl. Use headphones or earbuds at a low, comfortable volume for the full left-right alternating stereo effect. The visual stimulus is effective on its own without audio.
The Brightness slider dims the stimulus without affecting the background. The Size slider scales the shape. The RGB toggle cycles the color through the visible spectrum. The Blur toggle softens the edges of the shape. All controls can be adjusted before or during use.
Who is this for?
Appropriate for adults who want to
- Calm their nervous system between therapy sessions
- Reduce anxiety before a stressful event
- Support sleep preparation in a calm setting
- Practice a grounding skill discussed with their therapist
- Explore what bilateral stimulation feels like
- Manage daily stress without a clinical intervention
Not appropriate for
- Intentional trauma processing without a therapist
- People currently in mental health crisis
- Active psychotic symptoms
- Photosensitive epilepsy (without physician guidance)
- Children under 18 without parental and clinician guidance
- Use while driving or operating machinery
- Anyone whose clinician has advised against BLS
If we have not discussed bilateral stimulation and how it fits your current treatment plan, bring it up before using this tool. What you practice between sessions matters.
Your privacy
No personal health information is collected
This tool does not ask for, collect, store, or transmit any personal health information. Your browser loads the page and audio files from the website host only. No data is sent to any server, and nothing about your use of this tool is tracked or retained anywhere.
This tool is completely free. There is no premium version, no account required, and nothing to upgrade. It will stay that way.
How to use the tool
- Choose a motion mode: Phaser (sweeping light bar), Sliding (shape glides across the screen), Blinking (shape alternates sides), or Infinity (continuous figure-eight path)
- Select a shape, direction, size, and color that feel comfortable. There is no clinically superior choice. Use what feels calming to you.
- Choose an audio sound if using headphones: click, river, bird call, or singing bowl. Adjust volume as needed.
- Set your speed. The default (Grounded, 0.70 Hz) is appropriate for most self-guided use. Slower speeds are more settling.
- Press Play.
After your session
Sit quietly for a moment and notice how you feel. Ground yourself in the room: five things you can see, four you can feel, three you can hear. If the stimulus brought up any emotional content, that is worth discussing with your therapist.
On the Infinity mode
The figure-eight path is a continuous closed loop with no endpoint. Many people find it particularly settling because there is no anticipation of stopping and restarting. It runs slower than the other modes by default.
Speed reference
The speed slider controls how many times the stimulus travels left-right per second. Stay in the green zone for self-guided use. The default is pre-set to the Grounded range.
| Zone | Speed | Time per sweep | Appropriate for |
|---|---|---|---|
| Deep Calm | 0.30 Hz 3 tenths per second | ~3.3 seconds | Self-guided Sleep prep · Deep settling |
| Relaxed | 0.40–0.60 Hz 4–6 tenths per second | ~1.7–2.5 sec | Self-guided Deep relaxation |
| Grounded default | 0.70 Hz 7 tenths per second | ~1.4 seconds | Self-guided General calming |
| Alert | 0.80–1.00 Hz 8–10 tenths per second | ~1.0–1.25 sec | Use with care Mild anxiety |
| Clinical range | 1.10–1.20 Hz 11–12 tenths per second | < 1 second | Clinician-directed EMDR only |
Two different Hz scales in the tool — not the same thing.
Movement speed (speed slider): 0.30–1.20 Hz — These are fractions of one cycle per second describing how slowly the stimulus sweeps. At 0.30 Hz the stimulus completes one full left-right-left pass every 3.3 seconds.
Audio tone pitch (tone slider): 80–440 Hz — These are sound frequencies. 196 Hz is roughly a G note; 440 Hz is the A above middle C. This controls pitch, not speed. The two sliders are completely independent of each other.
About this tool
This tool was designed and built specifically for Walk of Life Counseling. It is not affiliated with any commercial BLS platform. Every comparable tool in this space either requires a professional subscription or is designed for therapists to use with clients in session. This one is designed for the person sitting alone who needs to settle their nervous system — no barrier, no account, no cost.
If you find it helpful, I hope it is one small part of a larger support system that includes the people in your life and, if you need it, a therapist you trust.
Ready to work with a trauma-informed therapist?
Walk of Life Counseling offers trauma-informed, evidence-based individual therapy for adults across Wisconsin via telehealth.
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By opening the tool, you confirm you have read the disclaimers above, you are not currently in crisis, and this tool is appropriate for your current situation.
Open the BLS Grounding Tool Opens in a new tab · Works on desktop, tablet, and mobileResearch references
- Boukezzi, S., et al. (2017). Bilateral alternating auditory stimulations facilitate fear extinction and retrieval. Frontiers in Psychology, 8. doi:10.3389/fpsyg.2017.00990
- Jarero, I., & Artigas, L. (2024). The Butterfly Hug method for self-administered bilateral stimulation. EMDR Master Class Series.
- Jarero, I. (2025). Technical report on the neurobiology of the Butterfly Hug: fMRI validation study. International Association of Trauma Professionals.
- Shapiro, F. (2018). Eye Movement Desensitization and Reprocessing (EMDR) Therapy: Basic Principles, Protocols, and Procedures (3rd ed.). Guilford Press.
- Amano, T., & Toichi, M. (2016). The role of alternating bilateral stimulation in establishing positive cognition in EMDR therapy. PLOS ONE, 11(10).
- World Health Organization. (2013). Guidelines for the management of conditions specifically related to stress. WHO Press.
- Kumpulainen, V., et al. (2025). Enhancing psychophysiological well-being through nature-based soundscapes. Psychophysiology. doi:10.1111/psyp.14760
- Deng, L., et al. (2025). Effects of nature sounds at different sound levels on recovery from noise-induced stress. Building and Environment.