This is an excerpt of the original blog, edited to pertain primarily to Brainspotting
This can be confused by even certified Brainspotting therapists, but there is a difference....
Bi-lateral music is used as a part of Eye Movement Desensitization Reprocessing (EMDR) therapy. The sound alternates between the left and right sides of the head in a steady, rhythmic pattern. The rhythmic shift is predictable and can be alerting to some.
BIO-lateral music was created by Dr. David Grand, the developer of Brainspotting (BSP), and is used as a part of Brainspotting therapy. It is hand panned to increase in volume in the left ear then decrease in volume before slowing increasing in volume in the right ear then decreasing, back and forth…rocking gently between the left and right hemispheres of the brain. It is intended to be played through headphones at a very low, almost imperceptible volume. Many people find it calming while also deepening access to the midbrain for deeper processing.
Bilateral and Biolateral music can be found readily online and through popular music platforms; however, it is always recommended that you try it first in the presence (physical or via Telehealth) of an attuned therapist to determine how your brain is likely to respond. If you and your therapist believe it fits for your process, you may use them at other times during your week or you may only use these types of music while working with your therapist. While the two can easily be confused, they are different. I recommend searching for “David Grand” or “Brainspotting” if you are looking for biolateral music, although other options do exist. I believe these free options qualify as biolateral.