Manas describes the higher mind which is beyond distraction and is both discerning and reflective. Tra means the tool or instrument of expression or emanation of manas. Mantrā is the vibrational generation of sound which works towards stilling and distilling of the thought patterns of the mind.
The pranava of Aum [Ōṃ], the primordial vibration of the universe, illustrates the effect of mantrā. Aum is the source of everything - it is an all encompassing sound, vibration and consciousness. Within Aum is the entire universe which is characterised as having five states or avastha.
1. Jagrat : waking and being awake conscious state in which there is attunement to the 5 senses. The principle of Creation is activated by the Rajas Guṇa through "Aaa" and it represents the pure creative energy of Brahma.
2. Svapna : dreaming and the dream state of liminal consciousness in which the dreamer sees the manas. The principle of Preservation is initiated by the Sattva Guṇa through "Uuu" which represents the pure balanced energy of Viṣṇu.
3. Sushupti : dreamless and deep sleeping unconscious state in which there is nothingness and prajñā [wisdom]. The principle of Dissolution is held by the Tamas Guṇa through "Mmm" which represents the energy of Śiva.
4. Turiya : silence of infinite state or absolute consciousness which invites witnessing of the Ātman, the transcendental Self.
5. Turyatita (that which is beyond) : maya or the illusion that denies and prevents manifestation and liberation of the infinite state of true awareness
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