Darkness Therapy In Treatment of Visual Brain Disorders Like Amblyopia

Depriving normal visual experience in one eye early in life produces a reduction in visual acuity (amblyopia) for that eye (blue circles) while the acuity of the other eye is normal (red). The visual acuity of the amblyopic eye remains low compared to the fellow eye, but after immersion in complete darkness the amblyopic eye very quickly recovers to match the visual acuity attained by the normal eye.
Credit: Current Biology, Duffy et al.

Researchers at Dalhousie University in Canada are using total immersion in darkness in the treatment and therapy for visual brain disorders such as amblyopia.

Amblyopia, also known as 'lazy eye', is a condition when one eye does not develop a proper nerve pathway to the brain. The other eye is unaffected by this and sends stronger neuro-electrical signals than the weaker one. This confuses the brain and eventually it ignores the signals coming from the weaker eye. This results in damaged and impaired vision.

Usual treatment for Amblyopia is to cover the stronger eye with an eye patch to force the weaker eye to strengthen and stimulate impulses for that eye. This allows the person to restore normal vision.

Treating Amblyopia during early childhood, especially before the age of 5, increases the chance of successfully treating it. The earlier it is detected, and the underlying cause corrected with spectacles and/or surgery, the more successful the treatment in equalizing vision between the two eyes.

Kevin Duffy and Donald Mitchell of Dalhousie University believe that darkness therapy, where the patient is immersed in total darkness is another way of treating amblyopia and other visual brain disorders without the use of surgery, drugs, and other procedures.