The engram is a transient or permanent mark of a memory on the brain. The concept was developed by Karl Lashly in 1950, in a classic paper entitled "In Search of the Engram," but it had previously been proposed by the German student of memory Richard Semon. Neuroscientists today believe that the brain records an event by strengthening the connections between groups of neurons that participate in encoding the experience. A new pattern of connections between different parts of the brain constitutes the brain's record of the event -- the engram. This idea was first suggested by the Canadian psychologist Donald Hebb, and has come to be known as "Hebbian Learning." (see Daniel L. Schachter, Searching for Memory, pp 57-59.)