title: The ontogeny of long-term memory over the first year-and-a-half of life.
abstract: This research documents the development of long-term memory in human infants from 2 months through the end of the first year-and-a-half of life. In the initial study phase, we trained 6- to 18-month-old human infants in an operant task and tested them after increasing delays until they exhibited no retention for 2 successive weeks. In the second phase, their data were combined with data previously obtained from 2- to 6-month-olds in an equivalent task. The resulting function revealed that the duration of retention increases monotonically between 2 and 18 months of age. This increase was not due to age differences in original learning. This is the first systematic analysis of the course of long-term memory across an extended period of infant development that is based on standardized parameters of training and testing. It provides a reference function against which measures of retention from infants of different ages that are obtained in different memory tasks with different parameters can be meaningfully compared.
authors.affiliation: Department of Psychology, Rutgers University, New Brunswick, NJ 08903, USA.
authors.forename: K
authors.initials: K
authors.lastname: Hartshorn
authors.forename: C
authors.initials: C
authors.lastname: Rovee-Collier
authors.forename: P
authors.initials: P
authors.lastname: Gerhardstein
authors.forename: R S
authors.initials: RS
authors.lastname: Bhatt
authors.forename: T L
authors.initials: TL
authors.lastname: Wondoloski
authors.forename: P
authors.initials: P
authors.lastname: Klein
authors.forename: J
authors.initials: J
authors.lastname: Gilch
authors.forename: N
authors.initials: N
authors.lastname: Wurtzel
authors.forename: M
authors.initials: M
authors.lastname: Campos-de-Carvalho
mesh_terms: D000367:Age Factors; D003216:Conditioning, Operant; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011939:Mental Recall; D002666:Psychology, Child; D012016:Reference Values; D012153:Retention, Psychology