From The Telegraph:
Late in 2005, the writer and neurologist Oliver Sacks, then aged 72, began to notice something odd during his habitual daily swim. While he did the backstroke, a pattern of close-set wavy lines and starry coruscations played on the ceiling above him. Sacks dismissed them as artefacts of his visual cortex, lingering symptoms from his frequent migraines. But a week before Christmas, as he entered a cinema, a more pronounced fluttering started up in his right eye.
By the time the film began, a quivering scotoma, or blind spot, had flared up before him “like a white-hot coal, with spectral colours”. Two days later he was diagnosed with a malignant melanoma behind the retina, and he wrote in his journal: “I am in the best possible hands, but I feel a terrified child, a child screaming for help, inside me.” Sacks’s own adventure at the edges of seeing – the cancer itself proved curable, but his vision was permanently impaired – forms the core of The Mind’s Eye. It is a reflection, in seven essays, on the optical effects of certain neurological disasters and on the response of the brain to partial or complete blindness.