Kiwako Ito

Prosody in First Language Acquisition – Acquiring Intonation as a Tool to Organize Information in Conversation

Recent research on children’s acquisition of prosody, or the rhythm and melody in language, demonstrates that young children use prosody in their comprehension and production of utterances to a greater extent than was previously documented. Spoken language, structured by prosodic form, is the primary input on which the mental representations and processes that comprise language use are built. Understanding how children acquire prosody and develop the mapping between prosody and other aspects of language is crucial to any effort to model the role of prosody in the processing system. We focus on two aspects of prosody that have been shown to play a primary role in its use as an organizational device in human languages, prosodic phrasal grouping, and intonational prominence.

Using Interactive Tasks to Elicit Natural Dialogue

Basic research into the relationship between intonation and speaker’s intentions about syntax and information structure addresses whether, when, and how speakers use prosodic information to signal linguistic and paralinguistic meaning. Speakers use prosody for a range of functions in communication: to mark the difference between immediately relevant vs. background information; to express contrast, contradiction, and correction; and to indicate the intended syntax of ambiguous utterances. In this paper, we review the methodologies used to examine intonation and sentence and discourse structure in language production studies. We focus on design conflicts that arise when experimental techniques need to generate a sufficient number of items for analysis, while simultaneously eliciting utterances that are representative of natural, conversational speech. We discuss the advantages and disadvantages inherent in (1) using spontaneous speech vs. various textbased elicitation techniques, (2) the effect of different levels of detail in instructions to speakers, and (3) the effects of manipulating the experimental environment. In the final sections, we present details of the method used in our own ‘tree decoration project’ as well as some preliminary cross-linguistic speech production data. These data include evidence for regularities in the realization of pitch accent placement and type in English discourse structure, and phonetic evidence for the intonational marking of discourse information status for accented and unaccented lexical items in Japanese.

Interpretation of Contrastive Pitch Accent in Six- to Eleven-Year-Old English-Speaking Children (and Adults).

Both off-line and on-line comprehension studies suggest not only toddlers and preschoolers, but also older school-age children have trouble interpreting contrast-marking pitch prominence. To test whether children achieve adult-like proficiency in processing contrast-marking prosody during school years, an eye-tracking experiment examined the effect of accent on referential resolution in six- to eleven-year-old children and adults. In all age groups, a prominent accent facilitated the detection of a target in contrastive discourse sequences (pink cat → green cat), whereas it led to a garden path in non-contrastive sequences (pink rabbit → green monkey: the initial fixations were on rabbits). While the data indicate that children as young as age six immediately interpret contrastive accent, even the oldest child group showed delayed fixations compared to adults. We argue that the childrens slower recovery from the garden path reflects the gradual development in cognitive flexibility that matures independently of general oculomotor control.

Semantically-Independent but Contextually-Dependent Interpretation of Contrastive Accent

A pair of eye-tracking experiments compared the effect of prominent pitch accent on pre-nominal intersective color adjectives and subsective size adjectives. Because subsective size adjectives are inherently contrastive, they may prompt comparison among a subset of referents regardless of the presence of prominent accent. In contrast, intersective color adjectives may require prosodic marking in order to be interpreted contrastively. Accent-driven contrast interpretation was tested within a real-world object manipulation paradigm, where participants followed pre-recorded instructions to decorate holiday trees. In both the Color and the Size experiments, a prominent accent (L + H*) on the adjective facilitated the detection of a contrastive target (e.g., Hang a red/medium star. → Next, hang a YELLOW/LARGE star.). When L + H* was infelicitously used in non-contrastive sequences (e.g., Hang a red/medium tree. → Next, hang a YELLOW/LARGE ball.), a reliable ‘garden-path’ increase in fixations to the incorrect contrastive competitor (e.g., yellow/large tree) was found in the Size but not in the Color experiment. As a result, the fixations to the correct target were visibly delayed in the Size experiment. In the Color experiment, the bias toward a contrastive interpretation was found regardless of accent type on the adjective. We argue that this was due to differences in the salience of visual contrast. While the present results confirm that L + H* on pre-nominal modifiers evokes an anticipatory contrast interpretation, they also suggest that the effect of accentual prominence is modulated by the discourse and referential context, rather than by the inherent semantics of accented words.

Do syllable-specific tonal probabilities guide lexical access? Evidence from Mandarin, Shanghai and Cantonese speakers

An eye-tracking study investigated how the interaction between syllable frequency and syllable-specific tonal probability guides online lexical access in speakers of mutually unintelligible Chinese dialects with three disparate tonal systems. Mono-dialectal Mandarin speakers, bi-dialectal Shanghai–Mandarin speakers and bi-dialectal Cantonese–Mandarin speakers searched for target Mandarin syllable–tone combinations while their eye movements and mouse clicks were recorded. The results showed dialectal differences in online eye fixation patterns but not in offline mouse responses. For all groups, mouse clicks were fastest for infrequent syllables with most probable tones and slowest for infrequent syllables with least probable tones. In online eye movement responses, only mono-dialectal Mandarin speakers showed an interaction between syllable frequency and tonal probability. Mono-dialectal Mandarin speakers’ fixations were fastest for infrequent syllables with probable tones and slowest for infrequent syllables with improbable tones. Mono-dialectal speakers also showed a greater amount of competition from the more probable segmental competitor when hearing improbable tones. Bi-dialectal speakers showed different timing in their integration of tonal probabilities. These findings suggest that highly bilingual speakers track and use Mandarin tonal probabilities, but their sensitivity to L2 tonal information may lag behind monolinguals for online word recognition.

Prominence perception is dependent on phonology, semantics, and awareness of discourse

ABSTRACT The perception of prosodic prominence is thought to be influenced by multiple competing factors. Three experiments tested the effects of phonological salience, discourse context and listener’s knowledge about the discourse on prosodic prominence judgements, using short adjective–noun phrases extracted from a corpus of spontaneous speech. These phrases had either a prominent L + H* 0 or a less prominent H* !H* pitch accent contour. The phrases were presented in a discourse context which either supported or did not support a contrastive interpretation of the adjective. Effects of the contrastive context to increase the perception of prominence only emerged for the phrases with the phonologically prominent L + H* 0 pitch accent sequence. Additionally, the magnitude of the contrast effect was correlated with the listener’s awareness of the discourse context, suggesting an ample interplay between linguistic context, pragmatic context, and phonology in prominence perception.

Linguistics in a Science Museum: Integrating Research, Teaching, and Outreach at the Language Sciences Research Lab

We describe the mission and practices of the Language Sciences Research Lab, a fully functional research lab embedded within a science museum. Within this environment, we integrate cutting-edge research, formal instruction, informal learning, and outreach to the public so that our work in each domain interacts with and enriches the others. We are guided by core concepts from the field of informal science education, and we strive to inspire excitement and expand both scholarly and public knowledge about the language sciences.

Contrast-marking prosodic emphasis in Williams syndrome: results of detailed phonetic analysis.

BACKGROUND Past reports on the speech production of individuals with Williams syndrome (WS) suggest that their prosody is anomalous and may lead to challenges in spoken communication. While existing prosodic assessments confirm that individuals with WS fail to use prosodic emphasis to express contrast, those reports typically lack detailed phonetic analysis of speech data. The present study examines the acoustic properties of speech prosody, aiming for the future development of targeted speech interventions. AIMS The study examines the three primary acoustic correlates of prosodic emphasis (duration, intensity, F0) and determines whether individuals with WS have difficulty in producing all or a particular set of the three prosodic cues. METHODS & PROCEDURES Speech produced by 12 individuals with WS and 12 chronological age (CA)-matched typically developing individuals were recorded. A sequential picture-naming task elicited production of target phrases in three contexts: (1) no contrast: gorilla with a racket → rabbit with a balloon; (2) contrast on the animal: fox with a balloon → rabbit with a balloon; and (3) contrast on the object: rabbit with a ball → rabbit with a balloon. The three acoustic correlates of prosodic prominence (duration, intensity and F0) were compared across the three referential contexts. OUTCOMES & RESULTS The two groups exhibited striking similarities in their use of word duration and intensity for expressing contrast. Both groups showed the reduction and enhancement of final lengthening, and the enhancement and reduction of intensity difference for the animal contrast and for the object contrast conditions, respectively. The two groups differed in their use of F0: the CA group produced higher F0 for the animal than for the object regardless of the context, and this difference was enhanced when the animal noun was contrastive. In contrast, the WS group produced higher F0 for the object than for the animal when the object was contrastive. CONCLUSIONS & IMPLICATIONS The present data contradict previous assessment results that report a lack of prosodic skills to mark contrast in individuals with WS. The methodological differences that may account for this variability are discussed. The present data suggest that individuals with WS produce appropriate prosodic cues to express contrast, although their use of pitch may be somewhat atypical. Additional data and future speech comprehension studies will determine whether pitch modulation can be targeted for speech intervention in individuals with WS.

Early L2 Spoken Word Recognition Combines Input-Based and Knowledge-Based Processing:

This study examines the perceptual trade-off between knowledge of a language’s statistical regularities and reliance on the acoustic signal during L2 spoken word recognition. We test how early learners track and make use of segmental and suprasegmental cues and their relative frequencies during non-native word recognition. English learners of Mandarin were taught an artificial tonal language in which a tone’s informativeness for word identification varied according to neighborhood density. The stimuli mimicked Mandarin’s uneven distribution of syllable+tone combinations by varying syllable frequency and the probability of particular tones co-occurring with a particular syllable. Use of statistical regularities was measured by four-alternative forced-choice judgments and by eye fixations to target and competitor symbols. Half of the participants were trained on one speaker, that is, low speaker variability while the other half were trained on four speakers. After four days of learning, the results confirmed that tones are processed according to their informativeness. Eye movements to the newly learned symbols demonstrated that L2 learners use tonal probabilities at an early stage of word recognition, regardless of speaker variability. The amount of variability in the signal, however, influenced the time course of recovery from incorrect anticipatory looks: participants exposed to low speaker variability recovered from incorrect probability-based predictions of tone more rapidly than participants exposed to greater variability. These results motivate two conclusions: early L2 learners track the distribution of segmental and suprasegmental co-occurrences and make predictions accordingly during spoken word recognition; and when the acoustic input is more variable because of multi-speaker input, listeners rely more on their knowledge of tone-syllable co-occurrence frequency distributions and less on the incoming acoustic signal.

THE EFFECTS OF PROCESSING INSTRUCTION AND TRADITIONAL INSTRUCTION ON L2 ONLINE PROCESSING OF THE CAUSATIVE CONSTRUCTION IN FRENCH

While previous research has shown that processing instruction (PI) can more effectively facilitate the acquisition of target structures than traditional drill practice, the processing mechanism of PI has not been adequately examined because most assessment tasks have been offline. Using eye-tracking, this two-experiment study compared changes in processing patterns between two types of training: PI and traditional instruction (TI) on intermediate-level L2 learners’ acquisition of the French causative. Both experiments used a pretraining/posttraining design involving a dichotomous scene selection eye-tracking task to measure eye-movement patterns and accuracy in picture selection while participants processed auditory sentences. Neither group received explicit information (EI) in Experiment 1 while both experimental groups in Experiment 2 received EI before processing sentences. Results of Experiment 1 revealed the PI group had significantly higher accuracy scores than the TI group. A change in eye-movement pattern was also observed after training for the PI group but not for the TI group. In Experiment 2, when both groups received EI, PI subjects were again significantly more accurate than TI subjects, but both groups’ accuracy scores were not reliably higher than subjects in the PI and TI groups in Experiment 1 who did not receive EI. Eye-movement patterns in Experiment 2 showed that both TI and PI started to shift their gaze to the correct picture at the same point as PI subjects did in Experiment 1. This suggests that EI helped the TI group start entertaining the correct picture as a possible response sooner but the EI did not help the PI group process the target structure sooner than the TI group.