Does infant memory expression reflect age at encoding or age at retrieval?
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.
Hartshorn
Kristin
K
Department of Psychology, Rutgers University, Piscataway, NJ 08854-8020, USA.
Rovee-Collier
Carolyn
C
D000367:Age Factors; D002657:Child Development / Q000502:physiology*; D003216:Conditioning, Operant / Q000502:physiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008568:Memory / Q000502:physiology*; D012054:Reinforcement, Psychology