Eyes are recognizable as bulges in an 18 days old embryo. These develop into optic pits a few days later. Retina starts differentiating at the fetal age of about 2 months. 4 months before birth, an immature fovea establishes at an absolute distance from the optic nerve head. This forms the basis for retinomotor functions. Vestibular system, which is very important for ocular movement development, is operational at 4 months of gestational age. Slow eye movements are present at this time, which become rapid and more frequent as the fetus grows. The peripheral retina in a new born is well developed as compared to the central area. Foveal acuity develops along with neurological development in a child. Improper anatomical development leads to defective visual functioning. If the retina is not developed, then it will lead to inappropriate signal transduction from retina onwards. Similarly, deficits lead to development of heterotropia, which is a big hindrance to binocularity. Anatomical development of all the structures is important.
Visual development occurs as the neurological development is taking place at prenatal as well as infancy stages. A child experiences and undergoes a number of primitive survival reflexes during this process of development. These primitive reflexes cease to persist after the required development has taken place. These reflexes are directed from the brainstem. These reflexes are closely linked to the vestibular system which is fully myelinated in utero.