- Even babies as young as 3 months show hippocampal activation tied to memory processing.
- Infant fMRI studies reveal babies recognize and remember repetitive patterns visually.
- Early non-declarative memory drives face recognition, routine tracking, and emotional bonding.
- Childhood amnesia stems from slow hippocampal maturation and limited verbal encoding.
- New technologies enable safe, accurate fMRI scans of awake, alert infants—transforming baby brain research.
If you can’t recall being a baby, you’re not alone. Most people experience “childhood amnesia,” a phenomenon where memories formed before the age of three are lost—or at least inaccessible—to conscious recall. But significant progress in infant fMRI now demonstrate the baby brain is more actively engaged in memory-making than previously considered. Scans of infants as young as 3 months old show notable activity within the hippocampus, the location of memory, challenging old assumptions and offering new comprehension into how babies start forming the basic elements of thought, learning, and emotion.
Why It’s Hard to Study Baby Brains
Studying the complex inner workings of a baby’s brain has always presented difficulties. The main tool for tracking brain activity—functional Magnetic Resonance Imaging (fMRI)—requires the subject to lie very still for long periods inside a loud, enclosed tube. For obvious reasons, this method doesn’t work well with the natural wiggling and unpredictability of infants.
Therefore, most infant brain scans for decades were done while babies slept. While this gave researchers a glimpse into resting-state connectivity and structural development, it didn’t answer more active questions, like: What parts of a baby’s brain activate when they process faces, songs, or parental voices? How does an infant’s brain respond to repeated stimuli—or new ones?
Infants don’t just passively exist in the world. They’re constantly taking in, reacting, and learning from their surroundings. To get a real picture of how baby brain development occurs, scientists needed ways to study the infant mind while it’s awake and alert.
Progress in Infant fMRI Technology
Now, a new period of innovation has arrived: researchers have spent the last ten years redesigning how fMRI studies are conducted, making it not only possible but safe to scan awake babies.
Here are some of the technological and methodological improvements making this change possible
- Shorter Scan Durations: Sessions are now divided into smaller parts to match infant attention spans and reduce stress.
- Sensory Adjustment: Scanners and labs are changed to lower loud noises, use soft lighting, and show baby-friendly visuals.
- Motion Compensation Algorithms: Even with trained technicians, babies will move. Advanced software helps adjust and re-align brain imaging quickly to reduce motion artifacts.
- Custom Head Stabilization: Comfortable positioning technologies allow babies’ heads to stay stable without feeling restricted.
- Parent Involvement: Babies are often with a parent nearby, offering comfort and support while the scan happens.
The outcome? For the first time ever, neuroscientists can observe real-time neural activity in infants actively interacting with stimuli—opening new paths in baby brain development research.
The Hippocampus Starts Working Early
One of the most interesting understandings from these infant fMRI studies is how early the hippocampus—important for memory—begins working.
Located in the inner folds of the temporal lobe and shaped like a seahorse (hence its name), the hippocampus has a key role in encoding and retrieving episodic memories. It acts like the brain’s filing cabinet, helping to package and store experiences for later use.
In the past, many neuroscientists thought the infant hippocampus was too undeveloped to support memory formation in any significant way. Structural growth of the hippocampus continues well into childhood, leading to assumptions that babies simply weren’t able to form memories—only simple reflexes or associations.
But new research is changing this idea.
According to recent data using infant fMRI, the hippocampus shows task-based activation in babies as young as three months. This means that although still developing, the hippocampus is already starting to process information related to memory formation, much earlier than expected.
What Babies Are Really Processing
A significant study published in Cell showed just how much infants are processing and remembering. Researchers showed awake infants sequences of visual images—some repeating, some new—and measured hippocampal activity using fMRI.
The results were surprising: when babies saw familiar images reappear in a controlled sequence, hippocampal activity significantly increased. What this indicates is that babies don’t just passively view the world—they are actively tracking patterns, recognizing recurring visuals, and encoding them.
This behavior is known as statistical learning, a basic form of learning that allows even very young infants to detect patterns in language, social behavior, and more. Hippocampal involvement suggests that babies aren’t just reacting in real-time but building internal models of their world based on gathered experience.
In short, the baby brain is not a blank slate. It’s an active, pattern-seeking machine—already forming the basis of infant memory.
What Kind of Memories Can Babies Form?
One important point is the type of memory infants are encoding. Adults rely heavily on declarative memory—explicit, verbally-reportable memories of events and facts. This includes episodic memory (e.g., “my birthday party last year”) and semantic memory (e.g., “Paris is the capital of France”).
Babies, however, mainly form non-declarative (implicit) memories, such as
- Recognition Memory: Identifying a caregiver’s face or a familiar toy.
- Procedural Memory: Learning routines or responses, such as expecting a bottle when hearing feeding sounds.
- Associative Learning: Linking cause and effect, like recognizing that a certain scent means bedtime is near.
Infant fMRI studies suggest that these implicit memory types are strong from an early age. Activation of memory-related structures supports the idea that infants are consistently remembering more than what we previously imagined—even if those memories aren’t accessible to them (or us) in adulthood (Riggins & Spencer, 2020).
This might explain why babies quickly learn and adjust to routines or show clear preferences for familiar faces, songs, or voices.
Why Don’t Adults Remember Being Babies?
If the infant brain can form memories from as early as three months, why can’t adults remember their infancy?
The reason for this is explained by the theory of childhood amnesia—the common inability to recall personal events from early childhood, especially before age 3 or 4. Several factors add to this phenomenon
- Incomplete Hippocampal Development: While active, the hippocampus continues maturing through early and middle childhood. Key substructures like the dentate gyrus and CA3 region are undeveloped in infancy.
- Lack of Language Encoding: Without expressive language, babies can’t name or describe experiences the way older children or adults can. This limits how memories are stored and later retrieved.
- Absence of Autobiographical Self: Infants lack the self-awareness needed to place events within a personal timeline. Memory without identity is harder to anchor in long-term recall (Bauer, 2007).
- Memory Format Mismatch: Early memories are likely stored in basic sensory or emotional formats, not matching the verbal, symbolic forms that adults use to remember.
So while the baby brain is busy creating experience-based memory traces, the inability to retrieve these as verbal narratives in adulthood contributes to the idea that infancy is a memoryless time.
Basic Elements for Thought and Emotion
Memory making isn’t just about storing facts. It has a key role in forming the baby’s emotional and cognitive basis.
Here’s how early memories affect long-term development
- Emotion Regulation: By learning that certain routines or objects are calming, infants begin developing internal regulation strategies.
- Attachment Styles: Babies form links between caregiver responsiveness and feelings of safety, which shape future relationship models.
- Expectation Formation: Recognizing patterns helps babies expect what comes next, reducing stress and encouraging learning about their world.
- Executive Function: Early prediction and memory skills improve attention control, decision-making, and problem-solving later in life.
In short, baby brain development isn’t just about storing memories—it’s about creating the mental structure that supports identity, learning, and well-being.
How the Infant Brain Grows Over Time
The hippocampus and surrounding brain regions continue developing well into adolescence, but the early years are especially active.
Structural MRI studies show the following milestones
- 0–12 Months: Fast increase in hippocampal volume and synaptic density. Neural circuits begin forming basic memory pathways.
- 1–2 Years: Increased connection between the hippocampus and prefrontal cortex, important for decision-making and memory consolidation.
- 3–6 Years: Development of more complex, narrative memory abilities and growing capacity for autobiographical recall.
This ongoing maturation supports the step-by-step change from implicit, sensory-driven memories to more complex, factual and episodic memory systems.
Language and Learning: It Starts With Memory
Even before infants can speak, their brains are busy making necessary connections between sound, meaning, and social context.
Early recognition memory helps babies
- Identify frequently heard words (e.g., their names).
- Link vocal tones with emotional cues.
- Recognize speech rhythms and native language structure.
- Learn through statistical parsing, where the brain figures out word boundaries by tracking which syllables tend to occur together.
Language, then, doesn’t come from nowhere—it’s built on repeated, remembered experiences. Memory is not just a tool for recalling the past; it’s the basis for future learning.
A New Era of Infant Neuroscience
Infant fMRI is changing developmental neuroscience in exciting and potentially significant ways.
Future implications include
- Early Detection of Neurodevelopmental Disorders: Unusual patterns in early hippocampal activity may indicate risks for conditions like autism, ADHD, or language delays.
- Predictive Modeling via AI: Machine learning algorithms trained on early fMRI data may help predict developmental outcomes based on early brain activity.
- Customized Interventions: Personalized learning or behavioral therapies may one day be designed to fit a child’s early neural profile.
But this exciting future is not without complexity.
Keeping Ethics Front and Center
As imaging technologies advance, ethical safeguards must keep pace. Working with infants demands a “do no harm” research model that places comfort, safety, and consent first and foremost.
Key ethical practices include
- Using infant-safe scanning protocols with low noise and reduced session length.
- Making sure caregivers are present and fully informed.
- Only continuing with the scan when the infant is alert, comfortable, and calm.
- Storing brain data securely, with strict confidentiality measures.
- Seeking approval from medical ethics boards and institutional review committees.
Respecting the dignity and developmental needs of infant participants ensures the field grows responsibly, with children’s well-being at its core.
What Parents and Educators Should Know
You don’t need lab equipment to support the complex work your baby’s brain is doing.
Everyday actions that help infant memory and cognitive development include
- Talking Early and Often: Describe daily activities. Your words help develop pattern recognition and language associations—even before baby talks back.
- Consistent Routines: Predictability builds memory reinforcement and gives babies a secure structure to expect and interact with their world.
- Repetition with Variation: Repeating songs, storybooks, and phrases helps reinforce recognition memory while adding small changes helps learning.
- Emotional Responsiveness: Warm, consistent interaction enables babies to build positive emotional associations—and powerful implicit memories.
By considering baby brain development understandings from infant fMRI, caregivers and educators can recognize every giggle, gaze, and cuddle as part of an ongoing neurological masterpiece.
Rethinking What Babies Really Remember
Infant fMRI is changing how we think about memory. The idea that infants as young as 3 months show hippocampal activity—reacting to patterns, encoding repeated visuals, and building rich internal maps—redefines what we thought possible.
Your baby may not be able to recount their early days, but their brain is still remembering—constructing the essential structure of trust, rhythm, identity, and knowledge.
And with this understanding, we ask: How can we shape those earliest memories—wordless but powerful—in a way that builds curious learners, emotionally grounded individuals, and compassionate hearts?
