Too Little Memory - Loss of memory
The patient named H.M. (Henry Gustav Molaison, February 26, 1926 – December 2, 2008) who lost his ability to remember new things
For a fascinating discussion of memory, it is helpful to look at the famous patient referred to as H. M. who has been studied for more than 40 years by Brenda Milner, a psychologist.
H.M., born in 1926, suffered a severe head injury that left him with epileptic seizures, which got worse with age, culminating in one major seizure and 10 blackouts every 7 days. In 1942, H.M. at age 16 had his first major seizure, and by his late 20s, H.M. was dysfunctional, of great harm to himself, and in need of dramatic intervention.
In 1953, the famed neurosurgeon William Scoville removed the inner surface of the temporal lobe (brain region located right behind eras) on both sides of the brain. This greatly helped the epilepsy, but left H.M. with catastrophic memory loss.
Following the surgery, H.M. lost the ability to convert a new short-term memory into a long-term memory. He could not encode new information. H.M. could meet you twice in two hours, with no recall of the first meeting. He lost the conversion ability Ebbinghaus described 50 years before.
Additionally, he could no longer recognize his own face in the mirror. Why? As he aged, the physical appearance of his face changed, but he could not process the new information and convert it into long-term memory. He was locked into a single idea about his appearance, and when he looked in the mirror, he could not identify to whom the aging image actually belonged.
Where Memories Go -- John Medina, author, Brain Rules, describes what was learned about memory from the removal of "H.M.'s" hippocampus.
H.M.s’ brain after the operation by Dr. William Beecher Scoville. In 1953, the majority of H.M.'s hippocampus, along with some surrounding neuronal tissue, was surgically removed from both hemispheres of his brain (area in red). Because of H.M., it is known that memory function originates in this region.
For additional insights into H.M.’s life, read the interesting October 2010 article in Esquire magazine. When a surgeon cut into Henry Molaison's skull to treat him for epilepsy, he inadvertently created the most important brain-research subject of our time — a man who could no longer remember, who taught us everything we know about memory. Six decades later, another daring researcher is cutting into Henry's brain.
Read more: http://www.esquire.com/features/henry-molaison-brain-1110#ixzz13rtps0w9