Mentioned in the Upanishads, specially in the Taittiriya, Chandogya and Mandukya Upanishads.
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In Jainism, Om is regarded as a condensed reference to the pancha paramedhi (A+A+A+U+M).Easoteric Buddhists place Aum at the beginning of their Vidya-Sadaksari (Om mani padme hum) as well in as most other mantras and dharanis. Ik Onkar, iconically represented in the Guru Granth Sahib, and is commonly translated ‘one God’ The Brahmi script Om ligature has become widely recognised in western counterculture since the 1960s.

Tibetan handicrafts made in India tend to use the Devanagari version.Om beach, located 6 km from Gokarna, a small temple town in the Uttara Kannada district of Karnataka, is so named because it is shaped like the holy, Hindu symbol.

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In music, the symbol is displayed on the cover of heavy metal band Soul fly’s third album.

What’s with the Om? The symbol embodies all three sound elements that go into the mystic, Hindu sound: the 3-shaped aa, the tail for oh and the bindi and half-moon for the mm, extended sonorously in intonation till it fades into its fourth sound element—a silence representative of inner silence. Om is placed at the beginning, and often, end, of Hindu prayers and texts, chanted in invocation, meditated upon through mindful chanting in the mind’s ear. In India it’s ubiquitous—seen in lockets, tattoos, posters, at, on and upon temples, homes, hospitals and businesses, heard on Om-chanting cassettes and CDs, ringtones and caller tunes. This mystic formula—first said to have cropped up in the Upanishads as “the quintessence of the essences”—is related in Hinduism to creation, to the Atma (individual soul) and the Brahman (world soul) realised as sound, to their union through yogic prac­tice, and to the third eye or crown chakra (associated with the pineal gland).
If there’s considerable debate over the Narendra Modi government’s vaunted success at getting the UN to declare June 21 International Yoga Day and the government keeping the associated literature and notices Om-free to avoid religious controvery, there has been much jubilation among those who believe there’s something mind- and body-changing about the pleasant feelings experienced on chanting Om. After all, they can now say there’s science to back what they knew all along: three scientists at the Centre of Biomedical Research of the Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, have taken ‘Om-ing’ a step further by studying the effects of listening to the mystic sound on the neural cortex of the brain. They did this by taking MRI and other images of brain activity of those who chant Om and comparing them with images from those who chanted other numinous sounds. The results, apparently, have been positive. Says Dr C.L. Khetrapal, the chief researcher, who is a distinguished professor at the institute and obtained his PhD in nuclear magnetic resonance back in 1965, “The findings of the present study specifically associating a neural region with emotional empathy, improvement of attention and motor skills is important. But further research is critical to establish the universal appeal of Om.” That’s putting it rather drily, but he emphasises that more social, cognitive and clinical scientists should be roped in to validate the findings of his team.
But the other two younger scientists on the project are extremely enthusiastic about the new findings. Dr Uttam Kumar, a social scientist who joined the centre in 2010, is convinced that Om is the best sound to make while meditating. “It activates areas of the bilateral cerebellum, left middle frontal gyrus and right precuneus….” That’s the drift. And Dr Anupam Guleria, a dynamic 31-year-old researcher who completed her PhD from IIT Kanpur three years ago, is working on yoga, meditation and functional magnetic resonance imaging with Om as one of the centrepieces of her research.
Their experiment aimed at demystifying Om had 21 participants from Lucknow, randomly selected from the age group 20-40 years. Their brains were scanned when they were instructed to passively listen to three randomly selected stimuli. The testing included three scanning sessions, each lasting 216 seconds. Everyone was made to listen to an arbitrary sound—Tom, acoustically matching Om. “But that didn’t do anything to relax them,” says Dr Uttam Kumar. “Since chanting Om has shown activation in the region involved in the regulation of emotion, we hypothesised that it triggers deep emotional empathy and its influence will be observed in the frontal region of the cortex that sparks off pleasant emotions.”
What’s better, their findings have been published in the reputed Cognition and Emotion Journal. In recent times, there has been an increasing tendency to offer scientific evidence to demonst­rate the beneficial effects of meditat­ion and yoga using modern tech­­nologies. Researchers at the Boston University School of Medicine have been using magnetic resonance spectroscopic imaging to show how meditation should be investigated as a complementary treatment for depression and anxiety disorders. And scientists at Harvard Medical School have reported how many traditional practices help tackle disorders and diseases.

Is Om the best sound to make while meditating? Those who believe so now have some science to feel good about.
So the functional neuroimaging study by the three Indian scientists has struck a chord. The 550-acre Lucknow institute they work in was set up in 1983 and has ample parks, an artificial lake, spacious sports complex and playgrounds. It also has sophisticated imaging equipment with computerised controls and recording instruments to observe what happens in the brain when various activities are undertaken.
Peter Diehl, former professor of physics at the University of Basel in Switzerland, says, “It’s interesting to note the influence of meditation on the brain through the MRI images. The quantitative comparisons are important, and the effects could be particularly interesting if applied in the cases of mentally depressed persons.” Still, some experts feel there’s much to be proved before the results can be said to be conclusive.
Prof Narayan Srinivasan, head and professor at the Center of Behavioral and Cognitive Sciences in Allahabad, says the Lucknow experimentations are a preliminary scratching of the surface. He speaks of the cultural conditioning and the expectations and beliefs it produces in Hindus that could significantly affect the results. Om may have such effects on those who share such beliefs but those who do not, such as people from a tribe in Africa, for instance, may remain unaffected by the chanting. It is also important, he says, to look at how age difference, gender difference, religious difference and differences in expectations about meditation in subjects can affect the results. Prof R.P. Tripathi, former head of the Center for Advanced Studies in Psychology, Allahabad, feels that a lot of questions remain unanswered. “We know that a large number of people have benefited from chanting Om, but one has to nuance it further and say how it produces substantial neurological, psychological and chemical changes over time.” Clearly, he wants more research—and more rigorous research—before any grand claims are made about Om being better than any other sound or mantra for meditation.
But for now, the three scientists from Lucknow feel that the biggest highlight of their experiment is the relationship of Om with emotional empathy, and producing changes in the brain that are critical for certain cognitive functions. Says Dr Uttam Kumar, “We used the most sophisticated methodology of brain mapping to see how the chant functionally activates different neural regions inside the brain. We wanted to see if we could apply this knowledge to treat various disorders and diseases.” It’s true that further studies are required, but Dr Khetrapal is optimistic that India could give a lead to the rest of the world in this direction.

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