________________
Samana
Physical level: Samana is the third prana. It operates between the navel and the diaphragm. The word samana is derived from the root saman, meaning 'equal' or 'balanced'. Thus it acts as a balancer or equalizer for the two opposite forces of prana and apana. Samana activates and maintains the digestive organs and their secretions, and is responsible for metabolism. It is associated with the digestive fire, jatharagni. Samana is experienced as a sideways movement of light, like the swinging of a fast pendulum, from right to left and left to right. It is responsible for the manipura experience of vitality and dynamism.
There are six major organs of digestion: liver, stomach, duodenum, spleen, and the small and large intestines, and all fall within the field of samana. The body receives its life support and healthy nourishment by the agency of samana. The distinctive feature of samana is that although it is a single force, it is capable of different activities in all these different organs.
Subtle level: Samana maintains the cohesion and balance between the koshas. It is subtle in comparison to apana and gross in comparison to prana. Just as it helps digest food, samana is also responsible for digesting the mind-stuff.
Indications of imbalance: Samana, the equalizer, is disturbed whenever one's mental peace and harmony are disturbed. Whenever there is turbulence in the body and the senses, samana becomes agitated and causes disorders. Poor assimilation of food is a result of samana imbalance, causing build-up of toxins as well as psychological blockage.
Udana
Physical level: Udana is the fourth manifestation, which operates in the extremities: the arms, legs, neck and head. This prana is responsible for all the sensory organs,jnanendriyas, and the organs of action, karmendriyas. It coordinates and controls the movements of the legs, arms and neck and directs the activities of the brain and sensory organs that are situated in the head region. These include: eyes, vision; ears, hearing;
5