Try recalling your earliest memory. If you’re like most of the population, it is likely that your earliest memory is between the ages of 2 and 3 years old. Although for some individuals it is possible to recall memories from as young as 5 months old. This form of memory loss is termed ‘infantile amnesia’.
So why do we have no recollection of our lives before this time? Freud originally postulated that this was as a result of some memory suppression, but his theory has since been discredited. Instead, the leading theory appears to be that a baby is lacking in self-perception, self-awareness, language, and other mental abilities required to encode memory. As a baby, you don’t know you are you.
Frankland and Josselyn, from the Hospital for Sick Children in Toronto, have theorised that the rapid birth of many new neurons in quick succession that occurs during early childhood, could block the ability to access old memories.
The brain’s ability to retain autobiographical information is attributed to the hippocampus. By manipulating the growth rate of hippocampal neurons, Frankland and Josselyn showed that young mice with a slowed rate of neuronal growth have a stronger ability to retain memory, than older mice with an increased amount of growth, who exhibited memory loss.
Is there any advantage to infantile amnesia? It’s likely. This time of early childhood is dedicated to building foundational knowledge before it attempts to create long-term memories, which is important to develop a healthy adult brain.
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