posted on 2017-11-15, 21:17authored byLakshmi Gogate, Madhavilatha Maganti
Purpose: This experiment examined English- or Spanish-learning preverbal (8–9 months, n = 32) and postverbal (12–14 months, n = 40) infants’ learning of word–action pairings prior to and after the transition to verb comprehension and its relation to naturally learned vocabulary.
Method: Infants of both verbal levels were first habituated to 2 dynamic video displays of novel word–action pairings, the words /wem/ or /bæf/, spoken synchronously with an adult shaking or looming an object, and tested with interchanged (switched) versus same word–action pairings. Mothers of the postverbal infants were asked to report on their infants’ vocabulary on the MacArthur–Bates Communicative Development Inventories (Fenson et al., 1994).
Results: The preverbal infants looked longer to the switched relative to same pairings, suggesting word–action mapping, but not the postverbal infants. Mothers of the postverbal infants reported a noun bias on the MacArthur–Bates Communicative Development Inventories; infants learned more nouns than verbs in the natural environment. Further analyses revealed marginal word–action mapping in postverbal infants who learned fewer nouns and only comprehended verbs (post–verb comprehension), but not in those who learned more nouns and also produced verbs (post–verb production).
Conclusions: These findings on verb learning from inside and outside the laboratory suggest a developmental shift from domain-general to language-specific mechanisms. Long before they talk, infants learning a noun-dominant language learn synchronous word–action relations. As a postverbal language-specific noun bias develops, this learning temporarily diminishes.
Supplemental Materials S1, S2, and S3. Eight dynamic video displays of four handheld objects—a fish, a dragonfly, a squiggly, or a lamb chop—looming or shaking in synchrony with a spoken word, /wem/ or /bæf/, were used. These displays were presented to English- and Spanish-learning infants in an identical manner in the experiment. On each display, a native speaker of Standard American English spoke one of the words once every 3 s while her visible hand (and forearm) held and moved one object each time she spoke the word. The words were elongated and exaggerated as in infant-directed speech and inflectionless akin to infants’ earliest spoken verbs.
Gogate, L., & Maganti, M. (2017). The origins of verb learning: Preverbal and postverbal infants' learning of word–action relations. Journal of Speech, Language, and Hearing Research, 60, 3538–3550. https://doi.org/10.1044/2017_JSLHR-L-17-0085
This research was conducted at Florida Gulf Coast University. It was supported in part by grants from the March of Dimes Birth Defects Foundation (12-FY08-155), the National Science Foundation (NSF, BCS 1123890) to Lakshmi Gogate, and the Department of Science and Technology (SR/WOS/-A/ET-143/2011), Government of India to Madhavilatha Maganti.