Ajna Chakra is situated within the Sushumna Nadi and its corresponding centre in the physical body is at the space between the two eye-brows. This is known as Trikuti. The presiding deity, Paramasiva (Shambhu), is in the form of Hamsa. There is Goddess Hakini (Sakti). Pranava (Om) is the Bijakshara for this Chakra. This is the seat of the mind.
There are two petals (Yoga Nadis) on each side of the lotus (Chakra) and the vibrations of these Nadis are represented by the Sanskrit letters:- (Ham) and (Ksham). This is the Granthi Sthana (Rudra Granthi). The Chakra is of pure white colour or like that of the full moon (on the Purnima day). Bindu, Nada and Sakti are in this Chakra. This Chakra corresponds to Tapo-Loka. The corresponding centre in the physical body is at the Cavernous Plexus.
He who concentrates at this centre destroys all the Karmas of the past lives. The benefits that are derived by meditation on this Chakra cannot be described in words. The practitioner becomes a Jivanmukta (liberated man while living). He acquires all the 8 major and 32 minor Siddhis. All Yogis and Jnanis too concentrate to this centre on the Bijakshara, Pranava!(OM). This is called Bhrumadya Drishti (gaze at the space between the two eye-brows).
When the Yogi reaches the Ajna Chakra or the centre between the two eyebrows he attains Samadhi and realises the supreme Self or Brahman. There is a slight sense of separateness between the devotee and Brahman.
Lalana Chakra is situated at the space just above Ajna and below Sahasrara Chakra. Twelve Yoga Nadis emanate from this centre. The vibrations that are made by the 12 Nadis are represented by the Sanskrit letters: (Ha, Sa, Ksha, Ma, La, Va, Ra, Ya, Ha, Sa, Kha and Phrem). It has OM as its Bija. At this centre the Yogi concentrates on the form of his Guru and obtains all knowledge. This has control over the 12 pairs of nerves that proceed from the brain to the different sense-organs.