The frontal bone is a very large domed shaped bone at the forehead. It is shaped like a shield and is rounded like a moon. It is part of the eye socket and forms part of the anterior fontanelle. Its interior concave surface houses the prefrontal lobes of the brain. Along this interior surface attaches the falx cerebri, the sheathing of connective tissue that supports and separates the two hemispheres of the brain.
The frontal bone has two very large sinuses, the frontal sinuses. These play an important role in sound production, and give a feeling of lightness to the anterior skull. These air pockets are critical for the sonar communication in cetacean’s underwater communication.
The frontal bone is home of the sixth chakra, the Ajna Chakra. This is the epicenter for inner knowing within the yoga system. The Ajna Chakra is on the central axis, relating to the Governing Vessel in Chinese Medicine. The Ajna relates to the fore-brain and the attachment site of the falx at the crista galli of the ethmoid bone. The Ajna Chakra relates to the pulsing secretions of the pituatary gland and the hypothalmus located just above it.
In meditation reflect on broadening the frontal bone by relaxing the skin at the center brow. Relax this skin both width wise and length wise. There should be a feeling of dilation at the center brow. Allow the skin covering the frontal bone to flow from the hair line down to the bridge of the nose.
Visualize the anterior portion of the frontal widening where the frontal lobes of the cortex lodge, packed tightly against the interior skull. Try and feel release in the left side of the frontal area. The meditation masters from Tibet insist that if the left frontal lobe slows in activity, profound relaxation ensues.