Bilateral Stimulation

Visual Bilateral Stimulation

Visual bilateral stimulation is the classical BLS modality in EMDR — a moving target the client tracks with their eyes. Learn how it is used and configured.

Reviewed by the BilateralSync clinical team · Updated · 5 min read

Introduction

Visual bilateral stimulation asks the client to follow a moving target with their eyes while holding a distressing memory in mind. It is the original modality Francine Shapiro described in 1989 and remains the default in most EMDR training and protocols.

Evidence summary

Experimental studies on eye movements during recall show consistent reductions in memory vividness and emotionality — an effect attributed to working-memory taxation. Comparative studies between visual, auditory and tactile BLS have not shown one modality to be universally superior; visual BLS remains the most widely trained modality.

Clinical use

Clinicians configure visual BLS around three parameters: pattern (horizontal, infinity, circular, pendulum), speed (typically 1–1.5 cycles per second for desensitization) and amplitude (wide enough to require actual eye movement, not just gaze shift). Online, the client's screen distance and size affect effective amplitude — BilateralSync exposes speed, size and pattern controls so the therapist can adjust on the fly.

Frequently asked questions

How wide should the eye movements be?
Wide enough that the client is genuinely moving their eyes, not just their attention. The client's screen size and viewing distance affect the setting online.
Can clients close their eyes and still do EMDR?
Yes — that's when auditory or tactile BLS is used instead of visual.

References

  1. Shapiro, F. (2018). EMDR Therapy, 3rd ed.