Research: Chanting Om Shown to Deactivate the Limbic System—a Known Treatment for Depression
In a study conducted at the National Institute of Mental Health and Neuroscience in India, chanting Om was found to have a similar effect as the implantation of a vagus nerve stimulator (VNS). The VNS, which requires invasive surgery and affects the vocal chords, has been shown to be beneficial in the treatment of both epilepsy and depression. But the same areas of the brain are affected with the chanting of “Om.” Both implantation of the VNS and ‘OM’ chanting produce limbic deactivation, the opposite of what happens when we are depressed or fearful or traumatized.
The researchers compared 15 seconds of “OM” (5 – O; 10 – m) to 15 seconds of the sound “Ssssss…” and to 15 seconds of rest. Using fMRI, as well as other measuring methods, the researchers found significant deactivation in the amygdala, anterior cingulate gyrus, hippocampus, insula, orbitofrontal cortex, parahippocampal gyrus and thalamus during ‘OM’ chanting. The “ssss” task did not produce any significant activation/deactivation in any of these brain regions. It is theorized that like the VNS, ‘Om’ chanting creates a vibration sensation around the ears that is transmitted through the auricular branch of the vagus nerve. This transmission would then deactivate the limbic system.
Bangalore G Kalyani, Ganesan Venkatasubramanian, Rashmi Arasappa, Naren P Rao, Sunil V Kalmady, Rishikesh V Behere, Hariprasad Rao, Mandapati K Vasudev, and Bangalore N Gangadhar “Neurohemodynamic correlates of ‘OM’ chanting: A pilot functional magnetic resonance imaging study” International Journal of Yoga. 2011 Jan-Jun; 4(1): 3–6.