Why don’t we remember being a baby? (Miramiska/Shutterstock)
Babies do form memories — they just can’t be retrieved later on
In a nutshell
- Babies do form memories. Brain scans show that by around 12 months, infants’ hippocampus — the brain’s memory center — is active during learning and linked to later recognition, suggesting babies can encode memories earlier than previously believed.
- The memories may not be lost, just inaccessible. The study supports the idea that “infantile amnesia” isn’t due to a failure to form memories, but rather a later inability to retrieve them.
- Different memory systems develop at different times. Even younger babies (as young as 3 months) show signs of statistical learning — recognizing patterns — while episodic memory (specific events) seems to emerge closer to the end of the first year.
NEW HAVEN, Conn. — Have you ever wondered why you can’t remember being a baby? This blank space in our memory, known as “infantile amnesia,” has puzzled scientists for years. Most of us can’t recall anything before age three or four. Until recently, researchers thought baby brains simply couldn’t form memories yet, that the memory-making part of our brain (the hippocampus) wasn’t developed enough.
But it turns out babies might remember more than we thought. Research just published in the journal Science shows that babies as young as one year old can actually form memories in their hippocampus. The study, led by researchers at various American universities, suggests our earliest memories aren’t missing, we just can’t access them later.
How Do You Study Memory in Babies Who Can’t Talk?
You can’t exactly ask a baby, “Do you remember this?” The researchers came up with a clever solution. They showed 26 babies (ages 4 months to 2 years) pictures of faces, objects, and scenes while scanning their brains. Later, they showed each baby two pictures side by side, one they’d seen before and one new one, and tracked where the babies looked.
“When babies have seen something just once before, we expect them to look at it more when they see it again,” says lead study author Nick Turk-Browne from Yale University, in a statement. “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.”
Getting babies to lie still in a brain scanner is no small feat. The research team has spent years developing special techniques to make this possible. They made the babies comfortable and only scanned them when they were naturally awake and content.
The Big One-Year Memory Milestone
The brain scans showed that when a baby’s hippocampus was more active while seeing a picture for the first time, they were more likely to stare at that same picture later, showing they may have remembered it.
This ability to remember showed a clear age pattern. Babies younger than 12 months didn’t show consistent memory signals in their brains, but the older babies did. And the specific part of the hippocampus that lit up, the back portion, is the same area adults use for episodic memories.
The researchers had previously discovered that even younger babies (as young as three months) can do a different kind of memory called “statistical learning.” This is basically spotting patterns across experiences rather than remembering specific events.
“Statistical learning is about extracting the structure in the world around us,” says Turk-Browne. “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.”
These different memory types use different pathways in the brain, with pattern learning developing earlier than specific event memory. This makes good developmental sense because babies need to learn how the world works before focusing on individual events.
So What Happens to Our Baby Memories?
This new research flips our understanding of infantile amnesia. The problem isn’t that babies can’t make memories; they clearly can. The mystery is what happens to those memories afterward. The researchers propose two possibilities.
“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,” says Turk-Browne.
The team is now testing whether kids can remember videos taken from their perspective when they were babies. Early results hint that these memories might stick around until preschool age before fading away.
“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,” says Turk-Browne.
Your baby brain was busy making memories long before you could talk about them. Those formative experiences might still be stored somewhere in your brain, you just can’t get to them. Though we’ll never consciously recall those first years, this research suggests those experiences weren’t lost to an undeveloped brain but encoded somewhere in our hippocampus, potentially shaping us in ways we’re only beginning to understand.
Paper Summary
Methodology
The researchers adapted memory research methods for infants who cannot verbally report memories or follow explicit instructions. Using a modified MRI setup with specialized equipment for infant comfort and safety, they scanned 26 infants aged 4.2 to 24.9 months while awake. Each infant viewed novel images (faces, objects, scenes) for 2 seconds during “encoding” trials. After a delay of 20-100 seconds, they were shown a “test” trial featuring the previously seen image alongside a new one, while eye-tracking technology measured which image they looked at longer. This visual paired comparison test uses infants’ natural looking behavior to assess memory without requiring verbal responses.
Results
The study revealed that when infants showed a familiarity preference (looking longer at the previously seen image), researchers could trace this back to higher hippocampal activity during the initial encoding phase. This effect was present across all participants but was most robust in infants older than 12 months. Memory effects were strongest in the posterior hippocampus—the same region heavily involved in episodic memory in adults. Memory signals were clearer for objects and scenes than for faces, and stronger for shorter versus longer delays between encoding and testing.
Limitations
Despite its groundbreaking nature, the study’s sample size of 26 infants, while substantial for challenging infant neuroimaging research, is relatively small. The fixed stimulus duration during encoding may not have given younger infants sufficient processing time. The single brief exposures to stimuli likely created relatively weak memory traces that may differ qualitatively from richer autobiographical memories. The research also can’t determine whether infant hippocampal encoding extends beyond simple recognition to include contextual information central to full episodic memories.
Discussion and Takeaways
This study provides the first direct neural evidence that infants can encode individual memories using the hippocampus beginning around one year of age. The findings contradict theories that infantile amnesia stems primarily from encoding deficits due to hippocampal immaturity. Instead, post-encoding mechanisms related to memory storage, consolidation, or retrieval may be responsible. The developmental emergence of hippocampal memory around 12 months corresponds with behavioral changes in infant memory abilities noted in previous research. The research suggests early experiences may influence development even if not consciously remembered later and raises questions about whether techniques might someday access these seemingly lost early memories.
Funding and Disclosures
The research was supported by several funding sources, including a National Science Foundation Graduate Research Fellowship to Tristan Yates, internal funding from Yale University’s Department of Psychology and Faculty of Arts and Sciences, support from the Canadian Institute for Advanced Research, and a grant from the James S. McDonnell Foundation. The researchers declared no competing interests.
Publication Information
The paper titled “Hippocampal encoding of memories in human infants” was authored by Tristan S. Yates, Jared Fel, Dawoon Choi, Juliana E. Trach, Lillian Behm, Cameron T. Ellis, and Nicholas B. Turk-Browne. It was published in the journal Science on March 21, 2025. Raw data and analysis code were made publicly available through repositories linked in the paper.
