A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve.

An abnormality of the functioning of the vestibular apparatus.

Inability to see well at night or in poor light.

Diminished clarity of vision.

An absolute or relative reduction in the extent of the normal field of vision.

An inherited retinal disease subtype in which the rod photoreceptors appear to be more severely affected than the cone photoreceptors. Typical presentation is with nyctalopia (due to rod dysfunction) followed by loss of mid-peripheral field of vision, which gradually extends and leaves many patients with a small central island of vision due to the preservation of macular cones.