(a) Role of the eye:

In japah, eyes are voluntarily fixed at the mid-point between the eye brows. The eye movements are controlled by three pairs of muscles:

    (i) The medial and lateral recti
    (ii) The superior and inferior recti
    (iii) The superior and inferior obliques

The medial and lateral recti contract reciprocally to move the eyes from side to side. The superior and inferior recti contract reciprocally to move the eyes upward and downward.

The nuclei of III, IV and VI cranial nerves (CN) and their innervations of the ocular muscles have inter connections through the medical longitudinal fascicular. Either through the fasciculus or by other associated pathways, each of the 3 set of muscles to each eye is reciprocally innervated so that one muscle of the pair relaxes while the other contracts.

Cortical control of the oculomotor apparatus spreads signals from the occipital visual areas through occipitotectal and occipitocollicular tracts into the pretectal and superior colliculus areas of the brain stem. In addition, a prefontal tract passes from the frontal cortex into the pretectal area.
 

In japah, superior rectus, inferior, oblique and medial rectus are the muscles which brings about the eye movement upwards and 45 degrees inwards from the vertical axis. This fixation also reflexly stimulates recticiular activating system which, in turn, activates the psyche of the practitioner and keeps him alert during japah.

Concentration in japah is directly proportionate to the prolonged intense fixation of gaze and the activation of praanan. Energy flowing outwards will gradually be turned inwards and upwards, thereby eliminating external disturbance-causing stimuli.

In the later and higher stages of japah and tapah following events can take place through the fixed gaze (fixed gaze = dristhi):

The opening of upanayana, the third eye of yoga. Dristhi targets the pineal gland, the III and the IV ventricles, hypothalamus and the limbic systems. In fact it plays very significant role in the progress of yoga.

The release, within the body, of enormous energy both electromagnetic and atomic where the gaze acts as detonator.

The rising of the internal sun, which shines for the aatman.

During the travel of aatman (Vishnu) beyond the human confinement of the body, praanan acts as the vehicle (Garuda) and the gaze acts as an accelerator.