Eye Movement Desensitization and Reprocessing (EMDR) is a treatment option initially designed to alleviate trauma-related distress by reducing physiological arousal. EMDR is a structured and interactive process that requires you to focus briefly on the traumatic memory. At the same time, your therapist utilises rapid eye movement technique by moving their finger back and forth in front of your face – asking you to follow these motions with your eyes to change the way the brain stores the particular memory.
Further information about EMDR is available here
https://www.apa.org/ptsd-guideline/treatments/eye-movement-reprocessing