What is Bilateral Stimulation?
Bilateral stimulation, or BLS, is perhaps the most famous component of EMDR. It is literally in the name (EM for Eye Movement, the original form of BLS).
Simply put, BLS is the method by which we repeatedly shift the brain’s attention across the midline of the body. The most notable methods are eye movements, physical touch (often on the outside of the knees) and audio tones.
Why do it?
By shifting the brain’s attention in this way, we are able to activate a normally dormant mechanism in the brain. Basically, we are adding a tremendous amount of horsepower to the brain. This allows the brain to process and resolve difficult material.
How it works.
How this works is currently up for debate, but here’s Adam’s theory:
Sleep researchers have long theorized that, during REM (or Random Eye Movement…did you catch that?) sleep, the brain is analyzing, sorting, and storing information. The argument is rather simple: people wake up with a clear head! (so to speak…cups of coffee not withstanding)
By intentionally engaging in the same eye movements present in REM sleep, we effectively “trick” the brain into turning on this usually dormant information processing mechanism. Once we switch it on, then we aim it at whatever we are trying to process, and, while continuing BLS, let the brain do its thing.
What is it like?
For the client, BLS is…weird. Having someone tap on your knees or wave their fingers in front of your eyes is not a common experience for most people.
Before engaging in BLS, the client will be instructed to fill their mind with a target memory. Once the client has the memory in mind (including images, emotions, beliefs, and even physical or sensory experiences), BLS will begin. The client will be instructed to allow the brain to process this memory. Once experiencing BLS, the client will notice various images, emotions, sensations and thoughts pass through their mind. One instructor uses the metaphor of riding on a train: you simple watch the scenery go by. No interpretation, correction, filtering or effort required.
Once undergoing BLS, one can think of the brain like a windup toy. Wind it up (preparation), point it in the general direction you want it to go (target acquisition), and then let go (reprocessing)! It is this last letting go part that is usually the most difficult for people. It is also the most critical.
For more information on EMDR and how it works, click here: What is EMDR?