Your Earliest Memories Might Still Exist – Science Just Found the Clues

For years, scientists believed that our first memories vanished because the brain wasn’t developed enough to store them. But groundbreaking Yale research suggests otherwise.

Infants can encode and recall memories—even if we can’t access them later in life. By using brain scans and eye-tracking, researchers found that when an infant’s hippocampus is more active, they are more likely to remember an image. This discovery challenges the idea of “infantile amnesia” and raises a fascinating question: Could our earliest experiences still be hidden deep in our minds, just beyond reach?

Memories from Infancy: A Surprising Discovery

We learn an incredible amount in our earliest years, yet as adults, we struggle to recall specific events from that time. Scientists have long believed this is because the hippocampus, the part of the brain responsible for memory, is still developing throughout childhood and isn’t capable of storing memories in infancy. However, new research from Yale challenges this idea.

In a recent study, researchers presented infants with new images and later tested their recognition. They found that when an infant’s hippocampus was more active upon first seeing an image, the child was more likely to recognize it later.

Published on March 20 in Science, these findings suggest that memories can indeed be encoded in the brain during infancy. The next step for researchers is to explore what happens to these early memories over time.

Infantile Amnesia: The Mystery of Forgotten Early Memories

The inability to recall specific experiences from the first years of life is known as “infantile amnesia,” but studying it presents unique challenges.

“The hallmark of these types of memories, which we call episodic memories, is that you can describe them to others, but that’s off the table when you’re dealing with pre-verbal infants,” said Nick Turk-Browne, professor of psychology in Yale’s Faculty of Arts and Sciences, director of Yale’s Wu Tsai Institute, and senior author of the study.

How Scientists Measure Memory in Babies

For the study, the researchers wanted to identify a robust way to test infants’ episodic memories. The team, led by Tristan Yates, a graduate student at the time and now a postdoctoral researcher at Columbia University, used an approach in which they showed infants aged four months to two years an image of a new face, object, or scene. Later, after the infants had seen several other images, the researchers showed them a previously seen image next to a new one.

“When babies have seen something just once before, we expect them to look at it more when they see it again,” said Turk-Browne. “So in this task, if an infant stares at the previously seen image more than the new one next to it, that can be interpreted as the baby recognizing it as familiar.”

Hippocampal Activity: A Key to Infant Memory

In the new study, the research team, which over the past decade has pioneered methods for conducting functional magnetic resonance imaging (fMRI) with awake infants (which has historically been difficult because of infants’ short attention spans and inability to stay still or follow directions), measured activity in the infants’ hippocampus while they viewed the images.

Specifically, the researchers assessed whether hippocampal activity was related to the strength of an infant’s memories. They found that the greater the activity in the hippocampus when an infant was looking at a new image, the longer the infant looked at it when it reappeared later. And the posterior part of the hippocampus (the portion closer to the back of the head) where encoding activity was strongest is the same area that’s most associated with episodic memory in adults.

These findings were true across the whole sample of 26 infants, but they were strongest among those older than 12 months (half of the sample group). This age effect is leading to a more complete theory of how the hippocampus develops to support learning and memory, said Turk-Browne.

Different Memory Pathways: Statistical Learning vs. Episodic Memory

Previously, the research team found that the hippocampus of infants as young as three months old displayed a different type of memory called “statistical learning.” While episodic memory deals with specific events, like, say, sharing a Thai meal with out-of-town visitors last night, statistical learning is about extracting patterns across events, such as what restaurants look like, in which neighborhoods certain cuisines are found, or the typical cadence of being seated and served.

These two types of memories use different neuronal pathways in the hippocampus. And in past animal studies, researchers have shown that the statistical learning pathway, which is found in the more anterior part of the hippocampus (the area closer to the front of the head), develops earlier than that of episodic memory. Therefore, Turk-Browne suspected that episodic memory may appear later in infancy, around one year or older. He argues that this developmental progression makes sense when thinking about the needs of infants.

“Statistical learning is about extracting the structure in the world around us,” he said. “This is critical for the development of language, vision, concepts, and more. So it’s understandable why statistical learning may come into play earlier than episodic memory.”

What Happens to Early Memories?

Even still, the research team’s latest study shows that episodic memories can be encoded by the hippocampus earlier than previously thought, long before the earliest memories we can report as adults. So, what happens to these memories?

There are a few possibilities, says Turk-Browne. One is that the memories may not be converted into long-term storage and thus simply don’t last long. Another is that the memories are still there long after encoding and we just can’t access them. And Turk-Browne suspects it may be the latter.

In ongoing work, Turk-Browne’s team is testing whether infants, toddlers, and children can remember home videos taken from their perspective as (younger) babies, with tentative pilot results showing that these memories might persist until preschool age before fading.

Could Early Memories Be Retrieved?

The new findings, led by Yates, provides an important connection.

“Tristan’s work in humans is remarkably compatible with recent animal evidence that infantile amnesia is a retrieval problem,” said Turk-Browne. “We’re working to track the durability of hippocampal memories across childhood and even beginning to entertain the radical, almost sci-fi possibility that they may endure in some form into adulthood, despite being inaccessible.”

Explore Further: Scientists Reveal Why We Can’t Remember Our Earliest Years

Reference: “Hippocampal encoding of memories in human infants” by Tristan S. Yates, Jared Fel, Dawoon Choi, Juliana E. Trach, Lillian Behm, Cameron T. Ellis and Nicholas B. Turk-Browne, 20 March 2025, Science.
DOI: 10.1126/science.adt7570

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