The Case Study of H.M.

HENRY MOLAISON • WHEN HE WAS 7 YEARS OLD HE SUFFERED A BICYCLE ACCIDENT RESULTING IN HIM HAVING INTRACTABLE EPILEPSY.

• AT AGE 27 HE UNDERWENT SURGERY IN ORDER TO REDUCE THE SEVERITY OF HIS EPILEPSY.

• HE LOST HIS MEMORY ON AN OPERATING TABLE IN AUGUST OF 1953.

THE OPERATION • CONSISTED OF REMOVING HIS HIPPOCAMPUS AND PARTS OF HIS TEMPORAL LOBE.

• HE WAS ABLE TO RECALL MEMORIES OF HIS CHILDHOOD, BUT NO LONGER REMEMBER ANYTHING OF HIS PAST CLOSE TO THE OPERATION.

• HE HAD ALSO SUFFERED A RETROGRADE MEMORY LOSS (A LOSS OF MEMORY PRIOR TO BRAIN DAMAGE) FOR ELEVEN YEARS BEFORE HIS OPERATION.

THE EXPERIMENTS • FOR 55 YEARS HENRY PARTICIPATED IN NUMEROUS EXPERIMENTS, MAINLY AT MASSACHUSETTS INSTITUTE OF TECHNOLOGY (MIT)

• PROFESSOR SUZANNE CORKIN AND HER TEAM EXAMINED HIM. • HE WAS ABLE TO LEARN AND REMEMBER A SET OF NUMBERS, BUT THIS MEMORY WOULD ONLY LAST FOR A SHORT PERIOD OF TIME. HE WAS STILL CAPABLE OF LEARNING NEW MOTOR SKILLS.

HIS DEATH • HENRY DIED ON DECEMBER 2, 2008, AT THE AGE OF 82. • THE STUDY OF MOLAISON CHANGED THE UNDERSTANDING OF HUMAN MEMORY. • UP UNTIL THEN IT WAS NOT KNOWN THAT THE HIPPOCAMPUS WAS ESSENTIAL FOR MAKING MEMORIES, AND IF WE LOOSE BOTH OF THESE PIECES OF OUR BRAIN IT CAN LEAD TO GLOBAL AMNESIA

• ONE THIS WAS REALIZED, THE FINDINGS WERE WIDELY PUBLICIZED SO THAT THIS OPERATION TO REMOVE BOTH HIPPOCAMPUS WOULD NEVER BE DONE AGAIN.

SOURCES • Memory - body, The Strange Case of H.M.. (n.d.). Retrieved from http://www.humanillnesses.com/Behavioral-Health-Fe-Mu/Memory.html • Jenni, Ph.D., O. (2012, January 16). HM, the Man with No Memory. Retrieved from http://www.psychologytoday.com/blog/trouble-in-mind/201201/hm-theman-no-memory • Newhouse, B. (2007, February 24). H.m.'s brain and the history of memory. Retrieved from http://www.npr.org/templates/story/story.php?storyId=7584970