Spanish-English speech perception in children and adults: developmental trends.

This study explored the developmental trends and phonetic category formation in bilingual children and adults. Participants included 30 fluent Spanish-English bilingual children, aged 8-11, and bilingual adults, aged 18-40. All completed gating tasks that incorporated code-mixed Spanish-English stimuli. There were significant differences in performance according to phonotactic construction of the stimuli, with fastest word recognition on words with voiceless initial consonants. Analysis of developmental trends revealed significant differences in children's performance by grade level and fastest recognition on English voiceless initial consonants than Spanish voiceless initial consonants. Differences in voice onset time between English and Spanish may have contributed to quicker recognition of English voiceless consonants than Spanish voiceless consonants. It is also possible that increased exposure to both spoken and written English may account for faster recognition of English voiceless words than Spanish voiceless words. In conclusion, multiple factors may influence perception of a second language.

A Rasch model prototype for assessing vocabulary learning resulting from different instructional methods: a preschool example.

This study explored the effects of using Rasch modeling to analyze data on vocabulary knowledge of preschoolers who participated in repeated read-aloud events and hands-on science activities with their classroom teachers. A Rasch prototype for literacy research was developed and applied to the preschool data. Thirty-one target words were selected for analysis from three children's informational picture books on light and color. After different instructional activities, each child received scores on individual target words measured with a total of six assessments, including free response vocabulary tests and expressive and receptive picture vocabulary tests. Rasch modeling was used to assess the learning difficulty of target words in different instructional settings. Suggestions are made for applying Rasch modeling to classroom studies of instructional interventions.