You might think you remember taking a trip to Disneyland when you were 18 months old, or that time you had chickenpox when you were 2—but you almost certainly don’t. However real they may seem, your earliest treasured memories were probably implanted by seeing photos or hearing your parents’ stories about waiting in line for the spinning teacups. Recalling those manufactured memories again and again consolidated them in your brain, making them as vivid as your last summer vacation.
People generally remember nothing from before age 3, and children’s memory abilities don’t fully mature until about age 7. “It’s a paradox in a sense,” says neuroscientist Flavio Donato of the University of Basel. “In the moment that the brain is learning at a rate it will never show again during the whole lifetime, those memories seem not to stick in the brain.”
For many years, researchers assumed babies’ brains are simply not mature enough to form lasting memories. Theories have abounded as to whether this is a biological immaturity or something more psychological, such as a lack of a sense of oneself as an individual or the ability to use language. Sigmund Freud, however, believed infants do form memories, but the brain suppresses them so we forget the psychosexual experience of birth. He called the process “infantile amnesia.”