Does the Direction of Eye Movements Matter in EMDR?

Does the Direction of Eye Movements Matter in EMDR?

Short Answer: Probably not in the simple way you might expect. Eye Movement Desensitization and Reprocessing (EMDR) traditionally uses horizontal, side-to-side eye movements, and that remains the most familiar approach. However, research has found that vertical eye movements can also reduce the vividness and emotional intensity of unpleasant memories. This suggests that the effect may depend more on performing an attention-demanding task while recalling a memory than on moving the eyes specifically from left to right. Researchers are still studying exactly which features of eye movements matter most.

Key Takeaways

• EMDR traditionally uses horizontal, left-to-right eye movements.
• Research has found similar memory effects from horizontal and vertical eye movements.
• There is not strong evidence that left-to-right movement is uniquely necessary for EMDR to work.
• One leading explanation is that eye movements compete with memory recall for limited working-memory resources.
• The speed, difficulty, and attention required by the movement may matter more than the exact direction.
• Eye movements are only one part of the larger EMDR process.

Why Does EMDR Usually Use Side-to-Side Eye Movements?

Horizontal eye movements are strongly associated with EMDR because they were part of the method's original development and remain widely used.

During a typical visual bilateral stimulation set, you follow a target moving from one side to the other while briefly keeping a memory, thought, feeling, image, or body sensation in mind.

Because this pattern alternates between the left and right sides of your visual field, it is often described as bilateral stimulation.

That does not necessarily mean the horizontal direction itself is the reason eye movements have an effect.

Researchers have tested that question directly.

What Happens With Vertical Eye Movements?

In experimental research, participants have been asked to recall unpleasant memories while moving their eyes either horizontally or vertically.

One study found that horizontal and vertical eye movements produced equivalent reductions in memory vividness and emotionality.

That finding is important because it challenges the idea that moving the eyes specifically from the left side to the right side is required.

If horizontal movement were uniquely necessary because of the way it alternates between the two sides of the brain, vertical movements would be expected to work differently.

Instead, both directions produced similar effects in that experiment. Distressing memories may also be part of what someone works on when dealing with PTSD.

Does This Mean Direction Does Not Matter at All?

Not necessarily.

Research supports saying that horizontal direction does not appear to be uniquely required, but that is different from saying every possible eye movement has been proven identical.

Eye-movement direction is only one variable.

Other factors may include:

• How quickly the eyes move
• How much attention the task requires
• How long each set lasts
• How easy or difficult the movement is to follow
• Whether the person is recalling a memory at the same time

Research into working memory suggests that the mental demand created by the eye-movement task may be particularly important.

What Does Working Memory Have to Do With Direction?

Working memory is the limited mental space you use to temporarily hold and work with information.

Recalling a vivid memory requires some of this capacity.

Following a moving visual target also requires attention and working-memory resources.

When you do both at the same time, the two tasks may compete for those limited resources. That competition may make the recalled memory temporarily feel less vivid or emotionally intense.

Studies supporting this explanation have found that eye movements can tax working memory and that more demanding eye-movement tasks can sometimes produce larger changes in memory vividness and emotionality.

This helps explain why the mental demand of the task may matter more than whether the eyes move horizontally or vertically. Similar memory and fear responses may also be relevant when someone is working with phobias.

Does EMDR Work by Activating the Left and Right Sides of the Brain?

You may encounter explanations claiming that horizontal eye movements work because they alternately activate the left and right sides of the brain.

That explanation has been proposed, but research does not support presenting it as the established reason EMDR works.

The finding that vertical eye movements can produce effects similar to horizontal movements is one reason researchers have questioned explanations based specifically on left-right brain communication.

Research has also found effects from attention-demanding tasks that do not involve horizontal eye movements at all.

For that reason, the working-memory explanation has received substantial attention.

What About Diagonal Eye Movements?

Diagonal eye movements have received less direct research attention than the traditional horizontal movements and the horizontal-versus-vertical comparisons.

Because the evidence is more limited, it would be too strong to claim that diagonal movements have been shown to work exactly the same way.

What the existing evidence does suggest is that the precise horizontal direction is not the only feature capable of producing memory-related effects.

The broader task—maintaining memory recall while performing another attention-demanding activity—may be more important.

Does the Direction Need to Alternate?

Traditional EMDR commonly uses repeated back-and-forth movement.

For example:

• Left to right, then right to left
• Up to down, then down to up

But researchers have also tested other dual-attention tasks that do not depend on bilateral or alternating eye movements.

A review of experimental findings described evidence that moving the eyes vertically can produce similar effects to horizontal movements and that entirely different attention-demanding tasks can also affect recalled memories.

This does not mean that the traditional EMDR procedure should be reduced to any random distracting activity. EMDR is a structured process, and eye movements are used within that larger framework.

It does mean that the exact left-right direction may not be the essential ingredient once thought.

Is Horizontal Movement Still the Standard Approach?

Horizontal eye movements remain one of the most recognizable and commonly used forms of bilateral stimulation in EMDR.

So if you have seen EMDR demonstrated with a dot, light, hand, or other target moving from left to right, that is normal.

The research on vertical movements does not mean horizontal movements are incorrect or outdated.

Instead, it tells us something about why the technique may work: the benefit does not appear to depend entirely on the eyes traveling specifically across the horizontal plane.

Can Eye-Movement Direction Be Different in Online or Self-Guided EMDR?

Yes. Visual bilateral stimulation can be delivered digitally, so the movement of the visual target can be controlled by software rather than by a therapist's hand.

With the Virtual EMDR self-guided program, bilateral stimulation is built into the online experience, and users can adjust available stimulation settings themselves.

The same broader principle applies in therapist-guided, online, and self-guided EMDR: the visual task needs to hold your attention while you remain engaged with the material you are working on.

The research does not support treating one particular horizontal direction as a magic ingredient.

Conclusion

EMDR traditionally uses horizontal, side-to-side eye movements, but research suggests that the exact direction is not the critical factor it may appear to be.

Experiments comparing horizontal and vertical eye movements have found similar reductions in the vividness and emotional intensity of unpleasant memories.

This finding supports the idea that the effect may come partly from dividing attention between memory recall and another mentally demanding task rather than from a unique left-to-right movement or a simple left-brain/right-brain mechanism.

Horizontal eye movements remain a standard and familiar part of EMDR, but the available evidence suggests that what your attention is doing may matter more than the precise direction your eyes travel.