Patient H.M.
By Luke Dittrich
Random House

You may already know the story of Henry Molaison, whose memory was removed by mistake in an experiment. But this retelling, by the grandson of the quick-to-cut surgeon who performed the operation, will still exercise your brain, as it has those of generations of psychology students. His identity guarded for decades, the 27-year-old patient was already absent, but in a different way, before treatment in 1953 to try to alleviate epilepsy that caused daily seizures.

In addition, his surgeon, William Beecher Scoville (whose own wife endured horrific treatments at a mental institution), believed the operation might provide insight into some of the more puzzling structures in the brain. Which is probably why, equipped with a suction catheter, Luke Dittrich’s grandfather vacuumed out bits of the medial temporal lobe (including the hippocampus), whose functions were a mystery. Gone for Molaison was much of the past and his future: he was now unable to form new memories. Dittrich’s book twists and turns with a little more flourish than is needed for this remarkable story. But even the excessive use of supposi­tion (“maybe” peppers the pages) cannot dull this disturbing tale about the author’s grandparents and Molaison’s grey matter.