Which of the following is TRUE regarding coical blindness?
Blindness that is the result of destruction of both visual and adjacent regions of the occipital lobes is termed coical or cerebral blindness. Normally the pupil constricts under a bright light (direct reflex), and the other unexposed pupil also constricts (consensual reflex). With complete or nearly complete interruption of the optic nerve, the pupil will fail to react to direct light stimulation; however, the pupil of the blind eye will still show a consensual reflex. Contrariwise, lack of direct and consensual light reflex with retention of the consensual reflex in the opposite eye places the lesion in the efferent limb of the reflex arc. A lesion of the afferent limb of the light reflex pathway will not affect the near responses of the pupil, and lesions of the visual pathway caudal to the point where the light reflex fibers leave the optic tract will not alter the pupillary light reflex. Ref: Ropper A.H., Samuels M.A. (2009). Chapter 14. Disorders of Ocular Movement and Pupillary Function. In A.H. Ropper, M.A. Samuels (Eds), Adams and Victor's Principles of Neurology, 9e.
Direct and consensual reflexes arc present in both the eyes
Direct and consensual reflexes absent in both the eyes
Direct reflex is present and consensual absent on the normal side
Direct reflex is absent on normal side and consensual reflex present