FEATURE · VISUAL STIMULATION · F2
A high-refresh target, right on the client's screen.
Visual bilateral stimulation with the same precision as an in-room light bar, delivered through the browser.
DEFINITION
Visual stimulation renders a smoothly moving target on the client's device that the client tracks with their eyes during EMDR reprocessing.
What it is
A canvas-rendered target that moves in one of seven configurable patterns at a speed the therapist sets. Colour, size and pattern update in real time.
Why it matters clinically
Visual BLS is the classical, most-studied form of EMDR bilateral stimulation. Smoothness, low latency and a distraction-free display preserve the oculomotor task and the therapeutic frame.
How BilateralSync implements it
The renderer runs on the client device at the display's native refresh rate. Pattern, speed, colour and size adjustments made by the therapist propagate to the client screen with sub-100 ms latency.
Frequently asked questions
How is the visual target rendered?＋
On an HTML canvas at the client device's native refresh rate. Motion runs through requestAnimationFrame so the animation stays smooth on desktop, tablet and phone.
Can I change speed and pattern during a set?＋
Yes. Every control on the therapist's side is reflected on the client screen with sub-100 ms latency, so mid-set adjustments are essentially instantaneous.
Does visual BLS work in fullscreen for the client?＋
Yes. The client can enter fullscreen for a distraction-free display. All chrome and controls are hidden on the client view by default.
Related reading
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.
Bilateral Stimulation
Bilateral Stimulation Patterns
An overview of common bilateral stimulation patterns used in EMDR — horizontal, infinity, circular and pendulum — and when clinicians choose each.
Bilateral Stimulation
Horizontal Eye Movements
Horizontal eye movements are the classical bilateral stimulation modality in EMDR. Learn why they are the default and how to configure them online.