Amazing story of Clive Wearing aflicted with 'memento' syndrome.

On March 29, 1985, Wearing, then an acknowledged expert in early music at the height of his career with BBC Radio 3, contracted herpes encephalitis. Normally causing only cold sores, in Wearing's case the virus attacked his brain. Primarily it damaged the hippocampus, which plays a major role in the handling of long term memory formation. Additionally, he sustained marginal damage to the temporal and frontal lobes. The former houses the amygdala, a component implicated in the control of emotions and associated memories.

Wearing developed a profound case of total amnesia as a result of his illness. Because the part of the brain required to transfer memories from the 'working' to the 'long term' area is damaged, he is completely unable to encode new memories. He spends every day 'waking up' every few minutes, 'restarting' his consciousness once the time span of his short term memory elapses. He remembers little of his life before 1985; he knows, for example, that he has children from an earlier marriage, but cannot remember their names. His love for his second wife Deborah, whom he married the year prior to his illness, is undiminished. He greets her joyously every time they meet, believing he has not seen her in years, even though she may have just left the room to fetch a glass of water.

http://en.wikipedia.org/wiki/Clive_Wearing