Segmentation is easy. Long-term retention in the service of bootstrapping is hard.

• In Event: 1-153 - Retention of statistical learning

Integrative Statement

We often measure language learning immediately after a single laboratory exposure. However, immediate encoding, what can be studied in a single session, is only one step of the language learning process. Learners, especially very young ones, may require multiple exposures to new information to acquire sufficient knowledge for bootstrapping future learning. We examine these steps in 7.5-month-olds using lexical segmentation.

Infants tend to missegment novel words that go against the metrical pattern of their native language (Jusczyk, Houston, & Newsome, 1999). Known words such as Mommy allow them to overcome this bias and segment novel iambic words correctly (Sandoval & Gómez, 2016). Known lexical information thus contributes to bootstrapping, enabling segmentation of adjacent words (Brent, 1999; Mattys, White, & Melhorn, 2005). We know little about how novel words become known words that can bootstrap segmentation, a topic we investigate here.

In Experiment 1, we familiarized 31 7.5-month-olds with sentences containing a repeated novel name (Lola) followed by novel iambic target words (e.g., ...Lola's beret...). Immediately after familiarization, we used the Head-Turn-Preference Procedure to test infants on iambic targets from the corpus and iambic control words not heard during familiarization. Infants failed to discriminate between the iambic targets and the iambic control words, t(30) = 0.20, p = .84, Mtarget = 9.24s, Mcontrol = 9.16s. Given that known names, enable segmentation of iambic targets (Sandoval & Gómez, 2016), we designed Experiment 2 to facilitate infants' learning of the novel name. Infants listened to an audio-story containing the novel name (Lola) every day for 14 days. Audio-recordings of the story varied across four talkers. Parents played the story before nap-time or bedtime, on average 54 minutes before their infant fell asleep. On the 15th day, the infants underwent the same familiarization and test procedure as in Experiment 1. Unlike Experiment 1, infants in Experiment 2 showed longer listening times to the iambic target words that followed Lola in the familiarization sentences than to the iambic control words they had not heard during familiarization, t(11) = 2.24, p = .046, Mtarget = 8.97s, Mcontrol = 7.91s. In Experiment 3, infants heard the story for 7 days and were tested on the 14th day, introducing a 7-day delay. Infants failed to discriminate between the iambic targets and the iambic control words, t(16) = 0.35, p = .73, Mtarget = 7.89s, Mcontrol = 7.61s. In Experiment 4, for which data collection is ongoing, we investigate whether 14 days of exposure to the story will result in discrimination on the 21st day.

Authors

• Michelle Sandoval, Wenatchee Valley College
  Non-Presenting Author

• Rebecca Gomez, The University of Arizona
  Presenting Author