Infantile Amnesia

Conflict of visions in psychology

• The fragility model tends to emphasize that hurt feelings constitutes real harm, whereas the antifragility model emphasizes that coddling does harm

• This is a conflict of visions even today in psychology and in universities all over the world.

Competing ideas about infantile/childhood amnesia

• Freud thought it was caused by trauma.

• Some Dissociative Identity Disorder theorists have suggested that DID is caused by very severe trauma before the age of 7

  • Blocked via amnesia for that childhood period

Definitions

• Infantile amnesia is the finding that almost all memories are lost before the age of 2 (or 3).

• Partial Childhood amnesia is the finding that adults has very few memories after age 3 to about age 10

Neurogenesis hypothesis - Nadel and Zola Morgan (1984)

• Say neurogenesis (growth of nervous tissue) in the hippocampus causes infantile amnesia

• Experiment on monkeys

  • Showed sudden appearance of certain capabilities before others

  • Shows the gradual emergence of cognitive and then later memory capabilities

Neurogenesis hypothesis - Josselyn & Frankland (2012)

• Study found

  • Rats have high neurogenesis in infancy and young rats don’t remember well

  • Guinea pigs have lower neurogenesis in infancy and young guinea pigs do remember well

• This suggest that neurogenesis has something to do with infantile amnesia

• As guinea pigs hippocampus undergo more neurogenesis in the womb

Dudycha 1941

• Infantile amnesia spans first 3.5 years of life

• Memories before this time may not be true memoires by remembrance of things told to us by others

Sense of self hypothesis - Howe & Courage (1993)

• Argue that infantile amnesia disappears as knowledge of self evolves

• Argue young children do have mature enough memory capability, so infantile amnesia may be due to a lack of sense of self

  • 2-year-old can remember when they were 1 but not then further in the future

• Our sense of self is not developed therefore we don’t remember these memories

• If we don’t have sense of self, we don’t store these memoires very well

• The theory makes sense logically and future research is needed to be researched empirically

Sense of self hypothesis - Howe (2019)

• The self is the glue that binds encoded elements together to create a strong trace for autobiographical memories

• Agrees neurogenesis explanation makes sense suggests it does correlate but not sure if it is causal

• Neurogenesis

  • New neurons overwrite old ones are memory sites

  • Neurogenesis is high during infantile amnesia period

  • Evidence that majority of early memory reports don’t involve emotional or traumatic events.

Summary

• As adults:

  • Almost nobody remembers anything at before age 2

  • Very few remember more than one thing before ages 3 to 6

  • Age 7-10 on average we remember between 1 or 2 things per year

• As children

  • 4 year olds do remember a lot from age 3, etc, but by the age on 20, most of that is lost

• Explanations:

  • Neurogenesis

  • Development of a sense of self

Readings

• universal cross-species phenomenon

• concept of self would help humans encode and store enduring personal memories

  • as infantile amnesia is observed in nonhuman species, it is unlikely that this phenomenon can’t be explained fully using purely human concepts

• Freud believed that our earliest memories were acquired and stored in pristine condition but actively repressed due to their emotionally and sexually charged content

• immature brain theory suggests that infantile amnesia results from the cortex not yet being “online” in infants