Childhood amnesia: Empirical evidence for a two-stage phenomenon

Abstract

The term childhood amnesia refers to the inability of adults to remember events from their infancy and early childhood. If we plot the number of memories that adults can recall as a function of age during childhood, the number of memories reported increases gradually as a function of age. Typically, this finding has been used to argue that gradual changes in memory development contribute to a gradual decline in childhood amnesia during the preschool period. Alternatively, it is possible that pooling data across participants has obscured more abrupt, stage-like changes in the remission of childhood amnesia. In the present study we examined the number and distribution of childhood memories for individual participants. Six adults were repeatedly interviewed about their childhood memories. We found that the distribution of adults' early childhood memories may be less continuous than pooled data suggest. This finding has important implications for current explanations of childhood amnesia.

Manipulating the reported age in earliest memories

“…Finally, the finding that asking about public-event knowledge and self-relevant knowledge had a similar effect on age estimates seems to be at odds with findings that extensive cueing renders earlier memories (Jack & Hayne, 2010). However, our self-relevant questions may have been too generic to provide an advantage over a natural tendency to self-generate cues based on autobiographical knowledge.…”

“…Roughly 40% of participating children (up to 12-13 years old) recalled events from before age 2, compared to 4% of adults. Jack and Hayne (2010) found that even adults can come up with memories from under age 2 when a timeline is combined with exhaustive interviewing.…”

Relearning a context-shock association after forgetting is an NMDAr-independent process

“…Independent samples t-tests revealed that in animals only exposed to the context at P17, MK801 given prior to conditioning at P27 significantly reduced the level of freezing exhibited the following day compared to saline-treated animals, t 10.94 = −3.40, p = .01. 2 This demonstrates that MK801 attenuated the acquisition of context conditioning for the first time. However, there was no effect of MK801 on re-acquisition in animals previously conditioned to the context at P17, t 16 = .22, p = .83.…”

“…For example, most adults do not remember events that occurred before they were 4 years old [1]. This effect is known as infantile (or childhood) amnesia [2]. Importantly, this phenomenon has been demonstrated extensively across species, and is observed even when levels of learning are equated across younger and older animals [3].…”

Ontogeny of memory: An update on 40 years of work on infantile amnesia

“…Subsequent studies that were more methodologically sound have essentially agreed that adults rarely remember events from their childhood that occurred prior to the age of 3,and memories for events that occur between the ages of 3-7 are sparse [10][11][12][13]. In recent years, a number of theories have emerged that attempt to explain infantile amnesia in the context of human cognitive and social developmental milestones.…”