OM meditation, also called praṇava upāsana, is the practice of mentally or audibly repeating the syllable OM (also written AUṂ) as the object of attention. The textual basis is in the Mandukya Upanishad (which devotes its full 12 verses to OM) and in Yoga Sutras 1.27 to 1.28, where Patanjali identifies OM as the name of Īśvara and prescribes its repetition along with reflection on its meaning. A daily session typically runs 15 to 30 minutes, seated upright, with the chant moving from audible to whispered to mental over the course of the session.
What the syllable contains
OM is written in Sanskrit as a single character but the Mandukya Upanishad analyses it as three sounds plus a silent fourth. Verse 8 names them:
- A: the waking state (jāgrat), the gross body, the syllable produced at the back of the open mouth.
- U: the dreaming state (svapna), the subtle body, the syllable produced as the mouth rounds.
- M: the deep-sleep state (suṣupti), the causal body, the syllable produced with closed lips and the resonance in the nasal cavity.
- The silence: the fourth (turīya), the awareness that contains the other three, the pause after the M dies away.
The meditation works by passing through the three audible parts and resting in the silence. The Mandukya Upanishad verse 12 says: “The fourth has no part, is beyond expression, the ending of phenomena, peaceful and non-dual. This is the Self, this is to be known.”
Patanjali’s prescription
Yoga Sutras 1.27 reads tasya vācakaḥ praṇavaḥ — “His [Ishvara’s] designation is the praṇava [OM]”. The next sutra, 1.28, prescribes taj-japas tad-artha-bhāvanam — “Repetition of it, and reflection on its meaning”. The instruction is doubly specified: chant the syllable, and contemplate what it stands for. The two together constitute the practice; either one alone is incomplete in Patanjali’s reading.
The technique step by step
- Sit in padmasana, siddhasana or sukhasana. Spine upright, hands in chin mudra or jnana mudra on the knees, eyes lightly closed.
- Settle the breath through 2 to 3 minutes of natural slow breathing.
- Begin audibly. On a slow exhalation, chant OM with the three sounds clearly articulated: A from the back of the throat (about a fifth of the exhale), U as the mouth rounds (about a fifth), M as the lips close (about three-fifths). The M is the longest portion.
- Pause in silence after each OM. The silence is the practice, not the interval between chants.
- Continue audibly for 10 to 20 rounds (5 to 10 minutes).
- Shift to whispered chanting for the next 5 to 10 minutes. The syllable is produced softly, almost inaudibly.
- Shift to mental chanting for the remaining time. The syllable is heard internally, without lip movement.
- End by sitting quietly for 2 to 3 minutes, allowing the resonance to settle, before opening the eyes.
Why the audible-to-mental progression
The Sanskrit term for the three modes is vācika (audible), upāṃśu (whispered) and mānasika (mental). The texts say mental chanting is the most powerful, but only after the gross modes have done their work; starting at mental chant tends to drift into thought rather than into the syllable. The audible chant gives the body something to anchor on (the breath, the throat, the vibration in the chest); the whispered chant tightens the focus; the mental chant releases the body and leaves the attention on the syllable alone.
Documented physical effects
Published EEG and functional imaging studies on OM chanting report:
- Vagal stimulation: the M sound, like other prolonged hum vibrations, stimulates the vagus nerve, shifting heart-rate variability toward parasympathetic dominance.
- Limbic deactivation: a 2011 fMRI study at AIIMS Delhi (Kalyani et al.) showed reduced activity in limbic structures (amygdala, hippocampus) during OM chanting, comparable to the deactivation seen with vagus-nerve stimulation in depression treatment.
- EEG alpha enhancement: increased alpha rhythm in posterior regions, consistent with a relaxed-but-aware state.
A practical observation
For what it’s worth, the most underrated part of OM meditation is the silence after the chant. Most practitioners chant briskly and rush to the next OM; the texts are explicit that the practice is the resting in the silence, with the chanted syllable as a periodic re-orientation. Sitting with the pause for as long as the chant itself doubles the value of the session. A 20-minute practice that is 7 minutes chant and 13 minutes pause produces a different state than 20 minutes of unbroken chanting.
Common questions
Is it OM or AUM?
Linguistically the same syllable, written one way and analysed the other. Sanskrit phonetics treats the syllable as a single sound (praṇava) that, when slowed, reveals the A-U-M structure. The Mandukya Upanishad does both: it speaks of OM as one and of A-U-M as three. The chanting practice uses the slowed form, the casual reference uses the contracted form.
Should the eyes be open or closed?
Both are traditional. Closed eyes are easier for beginners and during the mental-chant phase. Open eyes with a soft gaze ahead (or at a small altar) are recommended by some teachers for the audible-chant phase, since closed eyes during sustained loud chanting can produce drowsiness. Either is acceptable; pick the one that keeps you alert.
Is OM only for Hindus?
The syllable is shared across Hindu, Buddhist (where it is the first syllable of oṃ maṇi padme hūṃ) and Sikh traditions (the Mool Mantar opens with ik onkar, which is a related but distinct form). Its Vedic and Upanishadic roots are specifically Hindu, but the practice is not gated by religious affiliation in the source texts; Patanjali’s prescription in Yoga Sutra 1.28 is open to any practitioner of the sutras.
One limitation worth noting
The strongest claims about OM chanting (specific brainwave entrainment frequencies, gland activation, DNA effects) outrun the published evidence. The vagal-tone and limbic-deactivation findings are real and modest; the molecular-biology claims are not currently supported. The traditional benefits are framed in terms of consciousness and quietening of mind, which is the framing the source texts use and the one the modern evidence broadly supports.
For the textual sources see the Mandukya Upanishad and Patanjali’s Yoga Sutras, chapter 1, verses 27 to 28.
