You Must Remember This: What Makes Something Memorable?

07 Sep

One of the signature discoveries of cognitive neuroscience is that a structure called the hippocampus, deep within the brain, is intimately involved in creating memories. This fact was dramatically illustrated by a singular patient, Henry Molaison, who experienced severe epileptic seizures. In 1953, when Molaison was 27, doctors removed his hip­pocampus and nearby areas on both sides of his brain. The operation controlled his epilepsy, but at a price--from that time on, he was unable to remember the things that happened to him. He could learn skills, such as mirror writing, but would be puzzled by his expertise, because he could not recall having acquired it.

H.M., as he was known during his lifetime to protect his privacy, taught scientists three lessons. First, certain brain structures--the hippocampus and the amygdala, the brain’s emotion center--specialize in remembering. Second, there are different kinds of memory--the ability to recall facts, or personal experiences, or physical skills like riding a bike--each with its own properties. Third, memory is distinct from the brain’s intellectual and perceptual abilities.