詳しいガイド（英語）
Meaning and tradition
Hakini is the name of a goddess in tantric tradition associated with the ajna (brow) chakra, the center of command and insight. Hakini Mudra is therefore linked with the mind, and it is also called the Mudra of the Mind or Brain Mudra. It belongs to the hasta mudra systems popularized in modern yoga and tantric-influenced manuals, and is not a gesture described in the classical hatha yoga texts.
The five fingertips each carry an element: thumb is fire, index is air, middle is space, ring is earth, little is water. Touching every fingertip to its mate is read as bringing all five elements into balance.
How to practice
Sit in Easy Pose or Staff Pose with a tall spine. Lift the hands in front of the chest with the palms facing each other. Touch each right fingertip to its left partner: thumb to thumb, index to index, and so on. Keep the palms apart so the hands form a dome.
Hold the shape at chest height or, if the arms are comfortable, in front of the forehead. Box Breathing gives the mind a steady count, and Nadi Shodhana can be practiced before holding the gesture. Stay for 2 to 10 minutes, then release.
Tips and common mistakes
Keep the fingertip contact light; pressing hard cramps the hands.
Leave a gap between the palms. Unlike Anjali Mudra, where the palms press flat together, here only the fingertips touch and the palms stay apart. Unlike Padma Mudra, where the heel of the hand, the thumbs and the little fingers touch while the other three fingers open, here all five fingertips touch and nothing opens outward. Unlike Yoni Mudra, the fingers are not interlaced or pointing downward into a triangle; they meet tip to tip as a dome.
Keep the shoulders down and let the elbows float, supported by a cushion if needed.
Tradition vs. evidence
Claims that this gesture improves memory or brain function are traditional and have no solid research support. What is defensible is that a precise, symmetric shape held in front of you gives attention something to rest on, and that slow counted breathing helps most people feel calmer.