Yoga nidra aka yogic sleep is tangible for all levels of students.

Each brain state we travel through during our wake/sleep cycles correlates to specific experiences. 

These sessions can be in a reclined position or a supported seated position.

Yoga nidra works with the autonomic nervous system. The autonomic nervous system regulates processes of the body that take place without a conscious effort (heartbeat, breathing, digestion and blood flow).

Extra meditations, book references and some of my other favorites:)