Why You Can't Remember Being a Baby

Scientific Concepts, Discoveries, and Nature/Biological Phenomena

Infantile amnesia (what it is and why it’s named)

• Infantile amnesia: the inability to recall events from early childhood, even though infants can form memories.
• Freud’s contribution (1905): the phenomenon was first named and described by Sigmund Freud.

Evidence that infants can form and recall memories (Rutgers experiment)

• Conditioning/associative learning with a mobile:
  • Experimenter Carolyn Rovee-Collier (Rutgers University) tied a ribbon from a baby’s ankle to a mobile above the crib.
  • Babies learned that kicking moved the mobile and showed engagement/pleasure.
  • Later testing after delays showed babies remembered the association:
    • ~2-month-olds: memory lasting a couple of days
    • 6-month-olds: memory lasting weeks
• Conclusion: infant brains can learn, store, and retrieve—but this memory doesn’t persist into adulthood.

Brain structures involved in adult vs. infant memory

• Hippocampus: a key structure for forming/encoding episodic memories—turning experiences into replayable “episodes.”
• Adult network coordination: the hippocampus works with the prefrontal cortex to tag, store, and retrieve episodes.
• Immature infant circuitry:
  • Connections between the hippocampus and cortex are still developing.
  • The dentate gyrus (a “gateway” for new memories) is not fully wired until roughly ages 2–4.
• Takeaway: infants may form memories, but they cannot reliably consolidate them into long-term storage in the adult manner.

Neurogenesis as a memory “overwriting” mechanism (Toronto/SickKids work)

• Neurogenesis: production of new neurons, especially in the hippocampus early in life.
• Josselyn & Frankland hypothesis (2014):
  • The same growth process that builds circuits may also disrupt existing connections that hold memories.
• Mouse experiments:
  • Increasing neurogenesis in adult mice led to forgetting of previously learned tasks.
  • Slowing neurogenesis in infant mice helped them retain memories longer than normal.
• Publication: findings reported in Science.
• Counterintuitive conclusion: early-life forgetting may occur because the brain is too busy building itself—not because it cannot store information at all.

Role of self-recognition in autobiographical memory

• Autobiographical memory: memories where “you” are the main subject of the experience.
• Self-concept as a prerequisite: developmental psychologists Mark Howe and Mary Courage argued that a critical missing component is the sense of self.
• Mirror + rouge test:
  • A dot of rouge is placed on a baby’s nose and a mirror is shown.
  • < ~18–24 months: babies treat the reflection as another child and don’t touch the mark on their own face.
  • > ~18–24 months: babies recognize the reflection as themselves and reach for the mark.
• Claim: self-recognition emerges alongside the onset of autobiographical memory formation.
• Interpretation: difficulty remembering early childhood may relate to the absence of a stable “narrator-self” during that period.

Language as an organizing scaffold for lasting memory

• Catherine Nelson’s view: language doesn’t just describe memories—it structures them.
• Proposed mechanism:
  • Before speech: experiences are stored as raw sensory impressions (sound, texture, emotion, light) without an organizing framework.
  • With language—especially conversation about past events (e.g., “Remember when we went to the park?”)—children become better at forming memories that last.
• Metaphor: language gives memory a “skeleton,” helping convert fleeting impressions into organized, durable representations.

Cultural variation in earliest memory age

• Qi Wang (Cornell) reported that the age of earliest memories varies across cultures.
  • Western cultures: earliest memories often around 3.5 years, supported by frequent parental narration and personal storytelling.
  • Maori (New Zealand): earliest memories average around 2.5 years, supported by oral traditions emphasizing personal history.
  • Some East Asian cultures: earliest memories closer to age 4+, where early childhood narratives focus less on the individual.
• Conclusion: cultural storytelling practices can shift how far back memory reaches.

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Methodologies / Experimental Approaches Mentioned

• Mobile ribbon learning (Rovee-Collier):
  • Ribbon from ankle → mobile above crib
  • Measure kicking behavior and retention after delays (days/weeks)
• Rodent neurogenesis manipulation (Josselyn & Frankland):
  • Increase or slow hippocampal neurogenesis in adult vs. infant mice
  • Assess retention/forgetting of learned tasks
• Self-recognition mirror test (Howe & Courage):
  • Rouge mark on baby’s nose
  • Use mirror observation to test whether babies recognize the mark as on themselves

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Researchers / Sources Featured

• Sigmund Freud
• Carolyn Rovee-Collier (Rutgers University)
• Sheena Josselyn (Hospital for Sick Children, Toronto)
• Paul Frankland (Hospital for Sick Children, Toronto)
• Mark Howe
• Mary Courage
• Catherine Nelson
• Qi Wang (Cornell University)
• Journal source: Science (for the neurogenesis findings)