title: Development of long-term event memory in preverbal infants: an eye-tracking study.
abstract: The development of long-term event memory in preverbal infants remains elusive. To address this issue, we applied an eye-tracking method that successfully revealed in great apes that they have long-term memory of single events. Six-, 12-, 18- and 24-month-old infants watched a video story in which an aggressive ape-looking character came out from one of two identical doors. While viewing the same video again 24 hours later, 18- and 24-month-old infants anticipatorily looked at the door where the character would show up before it actually came out, but 6- and 12-month-old infants did not. Next, 12-, 18- and 24-month-old infants watched a different video story, in which a human grabbed one of two objects to hit back at the character. In their second viewing after a 24-hour delay, 18- and 24-month-old infants increased viewing time on the objects before the character grabbed one. In this viewing, 24-month-old infants preferentially looked at the object that the human had used, but 18-month-old infants did not show such preference. Our results show that infants at 18 months of age have developed long-term event memory, an ability to encode and retrieve a one-time event and this ability is elaborated thereafter.
authors.affiliation: Graduate School of Frontier Biosciences, Osaka University, Osaka 5650871, Japan.|Graduate School of Medicine, Osaka University, Osaka 5650871, Japan.|Precursory Research for Embryonic Science and Technology (PREST), Japan Science and Technology (JST), Tokyo 1020076, Japan.
authors.forename: Tamami
authors.initials: T
authors.lastname: Nakano
authors.affiliation: Graduate School of Frontier Biosciences, Osaka University, Osaka 5650871, Japan.|Graduate School of Medicine, Osaka University, Osaka 5650871, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kitazawa
mesh_terms: D002657:Child Development; D002675:Child, Preschool; D053483:Eye Movement Measurements; D005133:Eye Movements; D005260:Female; D005403:Fixation, Ocular; D006801:Humans; D007223:Infant; D008297:Male; D057567:Memory, Long-Term; D002666:Psychology, Child