Gravity relaxes the brain

When the abandonment to gravity comes into action, resistance ceases, fear vanishes, order is regained, nature starts again to function in its natural rhythm and the body is able to blossom fully, allowing the river of life to flow freely through all its parts.
Scaravelli p.115

Gravity relaxes the brain.  This will be possible only if you let the pull of gravity reach the top of your skull.
In this process the many nerves along the channel of the spinal cord will also find relief.
p.123