Friday, December 04, 2009

Memorial For A Brain


When I was in medical school I was fascinated by neuroanatomy and neuroscience. I enjoyed reading popular science books like Broca's Brain and The Three Pound Universe. I liked reading about the classic clinical cases studies that taught us a lot about how the brain works---cases like Phineas Gage, the Nineteenth Century railroad foreman whose brain injury revealed the purpose of frontal lobes, or the case of H.M., the man whose temporal lobectomy taught us about the how memory works.

Patient H.M. had parts of both his temporal lobes removed in order to treat a seizure disorder. After the surgery he was unable to form new memories at all, and he became one of the most-studied subjects in the field of neuropsychology. From H.M. we learned that there are two types of memory, declarative and procedural memory. Declarative memory is the what we use when we learned facts. Procedural memory is what we use when we learn how to do things, like brush our teeth or ride a bike. H.M's temporal lobectomy destroyed his declarative memory, but his procedural memory was left intact.

I'm bringing this up now because of an article in Wednesday's New York Times, "Dissection Begins on Famous Brain". Patient H.M., whose name we now know is Henry Molaison, died last year and donated his brain to a neuroscience project at M.I.T. They are in the process of sectioning his brain to learn more about what went wrong with it. There is even a web site, the Brain Observatory, where you can watch the sectioning as it happens.

I read the story and checked out the sectioning web site, but my reactions are mixed. As a psychiatrist it's fascinating to see that we can study a lesion from an individual patient all the way down to the microscopic level, but as a human being it leaves me feeling rather sad for this guy. It was noble of him to donate his brain, and years of his life, to science but on the other hand I can't help wondering if he ever just wished people would leave him alone.