Original sentence: Eye Movement Desensitisation and Reprocessing, also known by its abbreviation EMDR, claims to relieve the symptoms of Post traumatic stress disorder (PTSD) and other mental health problems using (in its orignal form) only movements of the eyes similar to those which occur naturally in REM sleep
Edited sentence: Eye Movement Desensitisation and Reprocessing, also known by its abbreviation EMDR, is purported to relieve the symptoms of Post traumatic stress disorder (PTSD) and other mental health problems using (in its orignal form) only movements of the eyes similar to those which occur naturally in REM sleep