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.
Reviewed by the BilateralSync clinical team · Updated · 4 min read
Introduction
Horizontal eye movements are the classical bilateral stimulation modality — a target moves side to side and the client tracks it with their eyes. This is the pattern Francine Shapiro described in 1989 and the one used in the majority of EMDR outcome research.
Evidence summary
Experimental studies of horizontal eye movements during recall consistently show reduced memory vividness and emotionality, with effects attributed to working-memory taxation.
Clinical use
Horizontal eye movements online require an appropriately sized target and viewing distance so that the client is actually moving their eyes, not just their attention. Speed is titrated to keep the dual task effortful without becoming overwhelming.
Frequently asked questions
- How is speed measured?
- Typically as cycles per second — one full left-to-right-to-left pass. 1.0–1.5 Hz is common for desensitization.
References
- Shapiro, F. (1989). Efficacy of the eye movement desensitization procedure.
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