This chapter provides an overview of how listeners’ brains process building blocks of speech: phonemes (that is, speech sounds) and word forms. Phonemes are processed bilaterally in posterior portions of the superior temporal sulcus. Compared to isolated phonemes, spoken words are acoustically more complex and associated with both grammatical status and meaning. Spoken word processing relies on bilateral temporal cortex, including portions of the superior temporal gyrus and middle temporal gyrus. The role of acoustic context on word recognition is also covered, including effects of speech rate and how listeners interpret speech sounds in relation to what surrounds them. Theoretical perspectives covered in the chapter include predictive coding (in which unpredicted sounds are associated with increased activity) and lexical competition (in which words with similar-sounding competitors are more difficult to understand). The hemispheric lateralization of these processes is also discussed, including the important historical development of the Wada test.

In this study, segmental and prosodic properties of word-length stimuli were assessed together. Six talkers from 5 L1 backgrounds (American English, Hindi, Korean, Mandarin, and Spanish) were recorded reading English stop-initial trochaic words. The productions were played for 20 monolingual American English-speaking listeners rated the accentedness of each talker. For each token, the deviation from native English productions was determined for segmental (VOT, vowel quality) and three prosodic properties (ratios of duration, intensity, f0 across the two syllables). For each non-native language background, a linear mixed-effects regression model was created to predict accentedness ratings from the phonetic deviations, and the significance of each fixed effect was examined. In each model, the significant predictors included both segmental and prosodic properties. For Hindi and Spanish talkers, the single best predictor was segmental; however, for Korean and Mandarin talkers, the single best predictor was prosodic. Thus, even for short stimuli, both segmental and prosodic information must be considered in accounting for accentedness judgments. We conclude that listeners are sensitive to the different ways that foreign accent may be manifested across different non-native backgrounds.