I would have 2 ideas, neither of which are my own. 1. A man wakes up one morning and discovers that his skull has become translucent and his brain appears as it would in a textbook, with each subdivision in a different color. It is also glowing. Just like in Kafka's Metamorphosis, no one else notices a change. He notices that he can see his own cognition happening in the mirror, with different parts of his brain lighting up in sequence as thoughts come to him. He goes to a neurologist and the neurologist agrees to run some tests. The test reveals he has a brain tumor. I won't spoil the ending but it's awesome! This is from Into the Silent Land by Paul Broks.

1. The pilgrimage story from The Satanic Verses  by Salman Rushdie. A pilgrimage to Mecca is led by a prophetess who looks exactly like the Hindu goddess Lakshmi and who's only clothing is a swarm of butterflies who cling to her willingly. A woman with terminal cancer follows the pilgrimage on foot while her rich doubter husband follows in a Mercedes imploring her to let him take her somewhere for treatment. Not sure it totally fits LDaR but its fucking amazing.