1)      Migraine

2)      Refractory errors -

3)      Hyperventilation

4)      Amblyopia – a unilateral or bilateral decrease of vision, 2-line difference of visual acuity between the 2 eyes, higher visual acuity with single letters than with a line of letters, difficulty in assessing the depth, amblyopia may be caused by squint, myopia, hypermetropia or astigmatism.

5)      Myopia – onset in childhood, progressive,