Kundalini Rising

Kundalini — Sanskrit कुण्डलिनी (kuṇḍalinī, 'coiled one') — is a concept from the tantric, yogic, and Śakta traditions of India describing a form of divine feminine energy (śakti) said to lie dormant at the base of the spine, coiled like a sleeping serpent, and to rise — under the influence of specific practices, spontaneously through spiritual experience, or occasionally as a crisis — up through the central channel (suṣumnā nāḍī) of the subtle body, activating the chakras in sequence, until it reaches the crown sahasrāra chakra, where its union with the transcendent consciousness Śiva constitutes enlightenment.

The phenomenology of kundalini rising is remarkably consistent across the practitioner literature. Experiencers commonly describe: intense heat or cold rising along the spine; involuntary body movements (kriyā); spontaneous vocalisations, including bīja mantras and glossolalia-like sounds; sensations of electrical current, vibration, or unfolding within the body; unusual perceptual openings (visions of light, auditory OM, geometric visuals); waves of ecstatic bliss or terror alternating unpredictably; and (in classical descriptions) the emergence of siddhis — psychic abilities such as clairvoyance, precognition, or telepathy. The classical texts warn that unprepared or premature kundalini activation can produce lasting difficulties (the kundalini syndrome recognised in some contemporary transpersonal-psychology literature).

Kundalini imagery appears widely in world mystical traditions, though under different names. The Chinese Taoist qi rising through the microcosmic orbit; the Christian mystical accounts of the Holy Spirit descending or ascending with fire and wind; the Sufi latā'if system; the Kabbalistic ascent through the sefirot: all describe closely related energetic phenomenology. Comparative-religion scholars — Mircea Eliade, Ken Wilber, Stanislav Grof — have argued that the underlying phenomenon is unitary, described differently by different traditions.

In contemporary psychedelic experience, kundalini-like activations are widely reported, particularly on MDMA (which produces the emotional-opening quality without the visionary intensity), on high-dose psilocybin (which more often produces the full visionary version), and on ayahuasca (which frequently produces the vomiting, shaking, and prophetic-vision phenomenology of a classical kundalini crisis). The tradition's standard advice — appropriate teacher, appropriate preparation, appropriate integration afterwards — has been adopted by much of the contemporary psychedelic-therapy field for precisely these reasons.

Sources:
Wikipedia — Kundalini
Wikipedia — Chakra