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Dvādaśānta ( Sanskrit: द्वादशान्त) or the Brahmarandhra, meaning – having an end or limit of twelve, it is the twelve fingers’ breath, the 12th centre (or śakti in an individual) identified by some with the pituitary gland, there being six centers in the brain and six below the brain. This term refers to – a) externally to the place where the breath dies away, b) internally to the crown of the skull and known as brahmarandhra, and c) above the skull to the dvādaśānta which is twelve fingers breadth away from the brahmarandhra, and when no longer identified with the body but with the all-pervading Shiva it is the Cosmic dvādaśānta, a wheel with a thousand spokes, eternally present. Dvādaśānta is like the triśūla signifying three kinds of energy – of the will, of knowledge and of activity. The initial extremity (ādi-koti) is the heart (whence the breath rises) but the final extremity (anta-koti) is the dvādaśānta (where the breath finally dies away or rests).
Abhinavagupta tells us that Shiva makes the sādhaka seek a worthy teacher and makes that teacher take up that task with extra responsibility and lead his śiśya towards liberation. The ānavopāya ('atomic') method utilises the creative functions of Shiva and raises the sādhaka to śaktopāya ('method of power') that employs the cognitive functions of the Lord. In this and other two succeeding methods mantra transmitted by the teacher to the śiśya plays a vital role. According to the Devyā-yāmala- tantra, the subtle breath composed of sound rising from the former’s heart moves through a series of centers to rest in the dvādaśānta which is the terminal point where the suśumnā ends and the central pathway of the three paths. Vijñānabhirava ( Dhāraṇā 28 shloka 51) states:-
यथा तथा यत्र तत्र द्वादशान्ते मनः क्षिपेत् | प्रतिक्षणं क्षीणवृत्तेर्वैलक्षण्यं दिनैर्भवेत् ||which statement means that the ānavopāya involves fixation of the mind again and again at ūrdhava dvādaśānta or bāhya dvādaśānta or āntara dvādaśānta which is the incomparable and ineffable state of Bhairava (an aspect of Shiva). This text had earlier in shloka 28 explained that meditation on prāṇaśakti arising from the mūladhārā chakra getting subtler and subtler dissolves in dvādaśānta to manifest Bhairava.
When the apāna remains in the dvādaśānta, it is known as the external kumbhaka (retention of breath as in a pot). When the '' prāṇa '' moves up to the nose-tip it is known as recaka and when it moves up to the extent of the dvādaśānta it is called external-recaka. The apāna moving inwards without the prāṇa is the internal-kumbhaka, and the apāna rising in the dvādaśānta attaining internal expansion is the internal-pūraka. According to Yoga Vasiśtha, the one who knows (experienced) these kumbhakas becomes liberated from the cycle of birth and rebirth; dvādśānta represents the highest seat of God in the body, the seat of the vibrating Self.