The Sound Barrier: Two-Year-Old Children's Use of Newly Acquired Words to Describe Preverbal Memories

Abstract

One of the proposed causes of childhood amnesia, the relative paucity of adults' memories for events occurring before the age of four, is the inability to verbally access preverbal memories. Although recent findings by Simcock and Hayne (2002) are consistent with this possibility, other researchers (Peterson & Rideout, 1998; Bauer, Wenner, & Kroupina, 2002) report some verbal access to memories acquired before the onset of productive language. The present research used the paradigm of color naming to further examine whether 2-year-old children can use newly acquired words to describe their preverbal memories. The method extended previous work by directly examining the acquisition of verbal labels and providing contextual support for memory performance. Participants learned a task requiring selecting a specific color. Those without color labels were taught them through eight structured sessions of age-appropriate color learning activities. After two months, the children's memory for the event was assessed verbally, then with visual cues, and finally through re-enactment. There were no group differences in implicit memory for the event (Fisher's Exact Test, p=0.31); children who knew the target label at encoding (n=20, mean age at recall 31.2 months), who acquired the label only after the intervention (n=8, M = 31.3 months), and who lacked the label at both pretest and posttest (n=9, M= 29.1 months) performed comparably in the re-enactment condition. Although 12 of 20 children who knew their target color word at the time of encoding could verbally access the memory at the time of recall, only one of 8 children who did not know their target word at encoding but learned it before recall could access the verbal label. However, this child incorrectly re-enacted the event. This research suggests that children cannot independently translate preverbal memories into words even with extensive task support. Therefore, language acquisition may indeed play an important role in the offset of childhood amnesia.