Bilateral Stimulation (BLS) in EMDR
A key component of Eye Movement Desensitization and Reprocessing (EMDR) is bilateral stimulation (BLS). BLS involves alternating stimulation of both sides of the body, activating the left and right hemispheres of the brain. This can be done through various sensory inputs, including:
- Visual – The therapist moves their finger back and forth, or a light bar is used, with the client’s eyes following the movement.
- Tactile – Gentle, rhythmic tapping alternates between the left and right sides of the body, such as tapping on the knees or shoulders.
- Auditory – Sounds, tones, or beeps alternate between the left and right ears via headphones.
Trauma and the Brain
Traumatic memories often become “stuck” in the brain’s emotional and memory-processing centers:
- Amygdala – The part of the brain responsible for processing fear and emotional responses.
- Hippocampus – The brain’s organizer of memories, which helps distinguish past from present.
When trauma occurs, these memories remain unprocessed, leading to heightened emotional reactivity whenever they are consciously or subconsciously triggered.
How BLS Helps Process Trauma
BLS is thought to engage both hemispheres of the brain, allowing traumatic memories to be processed in the prefrontal cortex (PFC)—the area responsible for rational thinking, decision-making, and emotional regulation.
Through BLS, the brain reprocesses distressing memories, shifting them from an emotionally charged and “stuck” state in the nervous system to a neutral, less distressing form. This process allows individuals to gain clarity, reframe past events, and reduce emotional reactivity.
Effects of Bilateral Stimulation
- Reduces the emotional intensity of distressing memories.
- Supports cognitive shifts, helping replace negative beliefs with more adaptive, positive ones.
- Promotes relaxation and desensitization to trauma triggers.
By facilitating these changes, BLS plays a key role in EMDR, helping individuals heal from past trauma and develop healthier emotional responses.
If you think that certain traumatic incidents might be impacting your responses to certain situations, relationships or experiences today, EMDR might be a fit for you. Call us today for a free consultation.
