Early Word Learners' Ability to Access Phonetic Detail in Well-Known Words

Abstract

Several recent studies from our laboratory have shown that 14-month-old infants have difficulty learning to associate two phonetically similar new words to two different objects when tested in the Switch task. Because the infants can discriminate the same phonetic detail that they fail to use in the associative word-learning situation, we have argued that this word-learning failure results from a processing overload. Here we explore how infants perform in the Switch task with already known minimally different words. The experiment involved the same phonetic difference as used in our earlier word-learning studies. Following habituation to two familiar minimal pair object-label combinations (ball and doll), infants of 14 months looked longer to a violation in the object-label pairing (e.g., label 'ball' paired with object doll) than to an appropriate pairing. These results using well known words are consistent with the pattern of data recently obtained by Swingley and Aslin (2002) in which it was found that infants of 14 months look longer to the correct object when the accompanying well known word is spoken correctly rather than mispronounced. We discuss how these results are compatible with the limited resource explanation originally offered by Stager and Werker (1997).

The Distribution of Talker Variability Impacts Infants’ Word Learning

“…Research by Gerken et al (2015) suggests that storing two stimulus dimensions is more demanding on infant pattern learning than storing a single dimension. Task demands are also known to impact word learning (Fennell & Werker, 2003;Yoshida et al, 2009). Rost and McMurray (2009) have called task complexity into question as a full explanation of 14-month-olds' word learning performance in the Switch paradigm, since increasing talker variability, which presumably increases task complexity, actually improves word learning.…”

“…Moving objects are commonly used in the Switch paradigm (e.g., Fennell & Werker, 2003). However, it is possible that the use of looming videos here increased the task complexity relative to the task used by Rost and McMurray (2009;.…”

Phonetic Detail in the Developing Lexicon

“…If, for example, the procedure of Stager and Werker (1997, Experiment 2) were not sensitive to subtle differences in the degree to which words are activated, MP effects would not be found. This alternative would be excluded if children in the same procedure did show MP effects on known words; studies of this sort are in progress (see Fennell & Werker, 2003, for a step in this direction).…”

Are U-Shaped Developmental Trajectories Illusory?

“…As a series of elegant studies has shown, the underlying discrimination ability persists, even as task demands determine whether infants can make this ability manifest or not (Fennell & Werker, 2003;Stager & Werker, 1997;Yoshida, Fennell, Swingley, & Werker, 2009). What was a simple discrimination task for an 8-month-old is construed as a wordlearning task by a 14-month-old because the child's relation to the task has changed in a qualitative way; the older child's attention is now focused on creating new mappings.…”