The ability of the eye with normal vision to see best a small part of the object it is looking at, while seeing everything else worse is known as the Central Fixation. In abnormal conditions of the eyes, this ability of central fixation is lost.
When the eye possesses the ability of central fixation, the eye has perfect sight and is perfectly at rest without any strain. Dr. W. H. Bates (see, What is Bates method of improving vision?) advised techniques or methods to regain the ability of central fixation. According to Dr. Bates, practicing the technique of regaining central fixation for an adequate period of time increases visual acuity, corrects errors of refraction, and helps in the treatment of functional disturbances of eyes, abnormal organic conditions of eye, inflammatory conditions of eyes and eye infections.