"Why don't we have any memories of our very first years of life?" Justine Meier asks us this question on our Facebook page. It's our reader question of the week. Thank you all for your participation.
We generally have no memory of our early years due to a phenomenon called infantile amnesia. For a long time, scientists thought the problem stemmed from the hippocampus, a brain region essential for episodic memory—that is, the memory of our personal experiences. The idea was that this "archivist" of the brain was not yet sufficiently developed in babies to properly record memories.
Memories are well preserved…
However, a study conducted by researchers at Yale University (United States), published in 2025 in the magazine ScienceThis hypothesis is called into question. Using MRI scans of 26 infants aged 4 to 25 months, researchers have shown that babies' hippocampi are capable of forming memories as early as one year old. To verify this, they used a method called "preferential looking": when a baby recognizes an image they have already seen, they look at it longer than a new image. The results show that the memories are indeed stored.
… but they are not “recovered”
So why don't we remember them later? According to researchers, the problem doesn't lie in the storage of memories, but in their retrieval. As we grow, our brains profoundly change the way they process sensory information. The "cues" that once allowed us to access these memories may no longer correspond to those used by the adult brain. In other words, the memories would still be there, but we would have lost the right keywords to find them.
Read alsoWhy do some memories remain, and others fade away?
Scientists are now continuing their research to understand more precisely how these early memories evolve during childhood and why they become so difficult to access in adulthood.
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