Drums can be used to trigger FREQUENCY FOLLOWING responses in the brain in the same way as Shamans have done so throughout the ages. The brain's frequency following response can be activated using repetitive drum beats to facilitate brainwave entrainment ( synchronization) to slower brainwave and patterns and states of consciousness. A repetitive drum rhythm of 8 beats per second for instance can be used to facilitate a brain wave pattern of around 8 hertz found in Alpha/ theta states. Drumming has been shown to be effective in reducing levels of anxiety if used in the right way. Jeff Strong, founder and director of REI, (RYTHM ENTRAINMENT INTERVENTION) institute, whose pioneering rhythm- based therapy is used in thousands of homes, schools and institutions recommends a minimum of 12 minutes of drumming to bring about changes in state. I sometimes use drumming within my sessions and generally at the end of sessions to help to ensure the client feels grounded before leaving, using a less repetitive rhythm when using it for for grounding purposes.