Categorization of Sounds

This is the author's accepted manuscript. This article may not exactly replicate the final version published in the APA journal. It is not the copy of record. The original publication can be found at http://psycnet.apa.org/index.cfm?fa=search.displayrecord&uid=2006-08586-015.The authors conducted 4 experiments to test the decision-bound, prototype, and distribution theories for the categorization of sounds. They used as stimuli sounds varying in either resonance frequency or duration. They created different experimental conditions by varying the variance and overlap of 2 stimulus distributions used in a training phase and varying the size of the stimulus continuum used in the subsequent test phase. When resonance frequency was the stimulus dimension, the pattern of categorization-function slopes was in accordance with the decision-bound theory. When duration was the stimulus dimension, however, the slope pattern gave partial support for the decision-bound and distribution theories. The authors introduce a new categorization model combining aspects of decision-bound and distribution theories that gives a superior account of the slope patterns across the 2 stimulus dimensions

The Effect of Instructed Second Language Learning on the Acoustic Properties of First Language Speech

This paper reports on a comprehensive phonetic study of American classroom learners of Russian, investigating the influence of the second language (L2) on the first language (L1). Russian and English productions of 20 learners were compared to 18 English monolingual controls focusing on the acoustics of word-initial and word-final voicing. The results demonstrate that learners’ Russian was acoustically different from their English, with shorter voice onset times (VOTs) in [−voice] stops, longer prevoicing in [+voice] stops, more [−voice] stops with short lag VOTs and more [+voice] stops with prevoicing, indicating a degree of successful L2 pronunciation learning. Crucially, learners also demonstrated an L1 phonetic change compared to monolingual English speakers. Specifically, the VOT of learners’ initial English voiceless stops was shortened, indicating assimilation with Russian, while the frequency of prevoicing in learners’ English was decreased, indicating dissimilation with Russian. Word-final, the duration of preceding vowels, stop closures, frication, and voicing during consonantal constriction all demonstrated drift towards Russian norms of word-final voicing neutralization. The study confirms that L2-driven phonetic changes in L1 are possible even in L1-immersed classroom language learners, challenging the role of reduced L1 use and highlighting the plasticity of the L1 phonetic system

Perception and production of Mandarin-Accented English: The effect of degree of Accentedness on the Interlanguage Speech Intelligibility Benefit for Listeners (ISIB-L) and Talkers (ISIB-T)

Previous research on the Interlanguage Speech Intelligibility Benefit (ISIB) indicates nonnative listeners may have an advantage at understanding nonnative speech of talkers with the same first language (L1) due to shared interlanguage knowledge. The present study offers a comprehensive analysis of various factors that may modulate this advantage, including the proficiency of both the listeners and the talkers, the mapping of phonemes between the L1 and second language (L2), and the acoustic properties of the phones. Accuracy scores on a lexical decision task were used to investigate both native English listeners’ and native Mandarin learners’ of English perception of native English and Mandarin-accented English speech. Results show clear ISIB-L and ISIB-T effects and demonstrate the dynamic nature of ISIB effects, with both being modulated by speaker and listener proficiency. More striking ISIB effects typically occur at the most extreme ends of accentedness. Additionally, an advantage for common-phoneme over unique-phoneme words in nonnative speech was observed. While nonnative productions of common-phoneme words are more accurate than those of unique-phoneme words, for the most accented productions, nonnative listeners are faster to respond to these unique, often mispronounced, productions. The nonnative listener advantage at perceiving nonnative speech depends on various factors, including listener proficiency, speaker proficiency, phoneme characteristics, and the acoustics of specific speech tokens

fMRI evidence for cortical modification during language learning

This is the publisher's official version, which the author has permission to share.Functional magnetic resonance imaging was employed before and after six native English speakers completed lexical tone training as part of a program to learn Mandarin as a second language. Language-related areas including Broca’s area, Wernicke’s area, auditory cortex, and supplementary motor regions were active in all subjects before and after training and did not vary in average location. Across all subjects, improvements in performance were associated with an increase in the spatial extent of activation in left superior temporal gyrus (Brodmann’s area 22, putative Wernicke’s area), the emergence of activity in adjacent Brodmann’s area 42, and the emergence of activity in right inferior frontal gyrus (Brodmann’s area 44), a homologue of putative Broca’s area. These findings demonstrate a form of enrichment plasticity in which the early cortical effects of learning a tone-based second language involve both expansion of preexisting language-related areas and recruitment of additional cortical regions specialized for functions similar to the new language functions

fMRI evidence for cortical modification during learning of Mandarin lexical tone

Functional magnetic resonance imaging was employed before and after six native English speakers completed lexical tone training as part of a program to learn Mandarin as a second language. Language-related areas including Broca's area, Wernicke's area, auditory cortex, and supplementary motor regions were active in all subjects before and after training and did not vary in average location. Across all subjects, improvements in performance were associated with an increase in the spatial extent of activation in left superior temporal gyrus (Brodmann's area 22, putative Wernicke's area), the emergence of activity in adjacent Brodmann's area 42, and the emergence of activity in right inferior frontal gyrus (Brodmann's area 44), a homologue of putative Broca's area. These findings demonstrate a form of enrichment plasticity in which the early cortical effects of learning a tone-based second language involve both expansion of preexisting language-related areas and recruitment of additional cortical regions specialized for functions similar to the new language functions

Speaker Sex Influences Processing of Grammatical Gender

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author’s publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Spoken words carry linguistic and indexical information to listeners. Abstractionist models of spoken word recognition suggest that indexical information is stripped away in a process called normalization to allow processing of the linguistic message to proceed. In contrast, exemplar models of the lexicon suggest that indexical information is retained in memory, and influences the process of spoken word recognition. In the present study native Spanish listeners heard Spanish words that varied in grammatical gender (masculine, ending in -o, or feminine, ending in -a) produced by either a male or a female speaker. When asked to indicate the grammatical gender of the words, listeners were faster and more accurate when the sex of the speaker “matched” the grammatical gender than when the sex of the speaker and the grammatical gender “mismatched.” No such interference was observed when listeners heard the same stimuli, but identified whether the speaker was male or female. This finding suggests that indexical information, in this case the sex of the speaker, influences not just processes associated with word recognition, but also higher-level processes associated with grammatical processing. This result also raises questions regarding the widespread assumption about the cognitive independence and automatic nature of grammatical processes

The Role of Surface and Underlying Forms When Processing Tonal Alternations in Mandarin Chinese: A Mismatch Negativity Study

This work is licensed under a Creative Commons Attribution 4.0 International License.Phonological alternation (sound change depending on the phonological environment) poses challenges to spoken word recognition models. Mandarin Chinese T3 sandhi is such a phenomenon in which a tone 3 (T3) changes into a tone 2 (T2) when followed by another T3. In a mismatch negativity (MMN) study examining Mandarin Chinese T3 sandhi, participants passively listened to either a T2 word [tʂu2 je4] /tʂu2 je4/, a T3 word [tʂu3 je4] /tʂu3 je4/, a sandhi word [tʂu2 jen3] /tʂu3 jen3/, or a mix of T3 and sandhi word standards. The deviant in each condition was a T2 word [tʂu2]. Results showed an MMN only in the T2 and T3 conditions but not in the Sandhi or Mix conditions. All conditions also yielded omission MMNs. This pattern cannot be explained based on the surface forms of standards and deviants; rather these data suggest an underspecified or underlying T3 stored linguistic representation used in spoken word processing

The role of linguistic experience in the hemispheric processing of lexical tone

This is the publisher's version, made available with the permission of the publisher.This study investigated hemispheric lateralization of Mandarin tone. Four groups of listeners were examined: native Mandarin listeners, English–Mandarin bilinguals, Norwegian listeners with experience with Norwegian tone, and American listeners with no tone experience. Tone pairs were dichotically presented and listeners identified which tone they heard in each ear. For the Mandarin listeners, 57% of the total errors occurred in the left ear, indicating a right-ear (left-hemisphere) advantage. The English– Mandarin bilinguals exhibited nativelike patterns, with 56% left-ear errors. However, no ear advantage was found for the Norwegian or American listeners (48 and 47% left-ear errors, respectively). Results indicate left-hemisphere dominance of Mandarin tone by native and proficient bilingual listeners, whereas nonnative listeners show no evidence of lateralization, regardless of their familiarity with lexical tone

Acoustic analyses and perceptual data on anticipatory labial coarticulation in adults and children

This is the published version, also available here: http://dx.doi.org/10.1121/1.394917.The present study investigated anticipatory labial coarticulation in the speech of adults and children. CV syllables, composed of [s], [t], and [d] before [i] and [u], were produced by four adult speakers and eight child speakers aged 3–7 years. Each stimulus was computer edited to include only the aperiodic portion of fricative‐vowel and stop‐vowel syllables. LPC spectra were then computed for each excised segment. Analyses of the effect of the following vowel on the spectral peak associated with the second formant frequency and on the characteristic spectral prominence for each consonant were performed. Perceptual data were obtained by presenting the aperiodic consonantal segments to subjects who were instructed to identify the following vowel as [i] or [u]. Both the acoustic and the perceptual data show strong coarticulatory effects for the adults and comparable, although less consistent, coarticulation in the speech stimuli of the children. The results are discussed in terms of the articulatory and perceptual aspects of coarticulation in language learning