Does infant memory expression reflect age at encoding or age at retrieval?

Kristin Hartshorn; Carolyn Rovee-Collier

doi:10.1002/dev.10101

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Does infant memory expression reflect age at encoding or age at retrieval?

Kristin Hartshorn·Carolyn Rovee-Collier

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Abstract

Do human infants express a memory acquired earlier in ontogeny in a manner appropriate to their age at encoding or their age at the time of retrieval? To answer this, we exploited the fact that retention is highly context dependent at 6 months but not at 8-9 months of age. Six-month-olds learned an operant response in one context, and their memory was maintained by monthly reinstatements in the original context. At 8 or 9 months of age, 1 month after the last (or only) reinstatement, infants were tested in either the same or a different context. During testing, infants' retention was no longer context dependent; rather, they responded robustly in both test contexts. These results revealed that infants expressed a memory acquired when they were younger in a manner appropriate to their test age. They were interpreted in terms of changes in the functional significance of context before and after infants self-locomote.

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Age Factors Child Development Conditioning, Operant Female Humans Infant Male Memory Reinforcement, Psychology Journal Article Research Support, U.S. Gov't, P.H.S.

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Kristin Hartshorn, Carolyn Rovee-Collier. 2003. Does infant memory expression reflect age at encoding or age at retrieval?. https://doi.org/10.1002/dev.10101

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