What the tradition describes
Kuṇḍalinī is described as a specific energy resident at the base of the spine — at the mūlādhāra chakra — that, when awakened, ascends through the central energy channel (the suṣumnā nāḍī) piercing each successive chakra on its way to the crown. The arrival at the crown (sahasrāra) is associated with the experience of unity with consciousness — the same state Patañjali calls samādhi.
First-person reports
Gopi Krishna's 1967 account is the most useful in English because it is candid about both the visionary content and the physical disruption. He describes years of disorientation, heat in the spine, and shifts in perception that he eventually integrated into a stable continuous awareness. Subsequent first-person accounts (Bonnie Greenwell's clinical research, Jana Dixon's compilations) document a recognisable pattern across many practitioners.
Honest cautions
The tradition itself has always treated kundalini activation as a serious matter best undertaken with a teacher who has been through it. Spontaneous activations — usually in people who have not been doing the formal practice — are well-documented and can be destabilising for months or years. Kundalini syndrome is recognised in transpersonal psychiatry; specialists including Lee Sannella have written useful clinical material. The energy itself is not pathological; what is pathological is having no map and no support.
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