I read in the SREE LALITHA SAHASRANAMA STOTRAM:
Muladharaika nilaya bramhagrandhi vibhedini
Manipurantarudita vishnugrandhi vibhedine
Aagyna-chakrantaralasdha rudra-grandhi vibhedini
What is the exact purpose of Bramha-grandhi , Vishnu-grandhi and Rudra-grandhi?
https://www.prana-sutra.com/post/the-three-granthis-yoga-brahma-vishnu-rudra
granthi = "knot".
Brahma Granthi is located between the Root and Sacral Chakra. It sits at the base of the spine, functioning as a primitive brain to guarantee survival. When the Brahma Granthi obstructs Kundalini energy, the mind becomes attached to mundane things.
Vishnu Granthi is located between the Sacral and Heart Chakra – two energy centers concomitant to emotional bondage, attachment, and psychic abilities. It keeps a person tied to self-cherishing his/her accumulations in a never-ending quest for power.
Rudra Granthi is located in the region of the Ajña (Third-Eye) chakra. The knot of Rudra is the final hurdle to overcome for a yogi. It resides in the Ajna Chakra, where the Ida, Pingala, and Sushumna merge to enter the Crown Chakra. It inhibits Kundalini from entering the highest self by binding it to mental attachments.
Reference to the 7 chakras in Hinduism
has direct scriptural citations.
