Publications

Abstract

The present paper assesses discourse-pragmatic factors as a potential explanation for the subject-object assymetry in early child language. It identifies a set of factors which characterize typical situations of informativeness (Greenfield & Smith, 1976), and uses these factors to identify informative arguments in data from four children aged 2;0 through 3;6 learning Inuktitut as a first language. In addition, it assesses the extent of the links between features of informativeness on one hand and lexical vs. null and subject vs. object arguments on the other. Results suggest that a pragmatics account of the subject-object asymmetry can be upheld to a greater extent than previous research indicates, and that several of the factors characterizing informativeness are good indicators of those arguments which tend to be omitted in early child language.

Abstract

Infants learn the meaning of words from accumulated experiences of real-time interactions with their caregivers. To study the effects of visual sensory input on word learning, we recorded infant's view of the world using head-mounted eye trackers during free-flowing play with a caregiver. While playing, infants were exposed to novel label-object mappings and later learning outcomes for these items were tested after the play session. In this study we use a classification based approach to link properties of infants' visual scenes during naturalistic labeling moments to their word learning outcomes. We find that a model which integrates both highly informative and ambiguous sensory evidence is a better fit to infants' individual learning outcomes than models where either type of evidence is taken alone, and that raw labeling frequency is unable to account for the word learning differences we observe. Here we demonstrate how a computational model, using only raw pixels taken from the egocentric scene image, can derive insights on human language learning.

Abstract

Psycholinguistic studies of metaphor processing must control their stimuli not just for word frequency but also for the frequency with which a term is used metaphorically. Thus, we consider the task of metaphor frequency estimation, which predicts how often target words will be used metaphorically. We develop metaphor classifiers which represent metaphorical domains through Latent Dirichlet Allocation, and apply these classifiers to the target words, aggregating their decisions to estimate the metaphorical frequencies. Training on only 400 sentences, our models are able to achieve 61.3 % accuracy on metaphor classification and 77.8 % accuracy on HIGH vs. LOW metaphorical frequency estimation.

Abstract

Studies have shown that cross-linguistically, consonants at the left edge of higher-level prosodic boundaries tend to be more forcefully articulated than those at lower-level boundaries, a phenomenon known as domain-initial strengthening. This study tests whether similar effects occur in Turkish, using the Autosegmental-Metrical model proposed by Ipek & Jun [1, 2] as the basis for assessing boundary strength. Productions of /t/ and /d/ were elicited in four domain-initial prosodic positions corresponding to progressively higher-level boundaries: syllable, word, intermediate phrase, and Intonational Phrase. A fifth position, nuclear word, was included in order to better situate it within the prosodic hierarchy. Acoustic correlates of articulatory strength were measured, including closure duration for /d/ and /t/, as well as voice onset time and burst energy for /t/. Our results show that closure duration increases cumulatively from syllable to intermediate phrase, while voice onset time and burst energy are not influenced by boundary strength. These findings provide corroborating evidence for Ipek & Jun’s model, particularly for the distinction between word and intermediate phrase boundaries. Additionally, articulatory strength at the left edge of the nuclear word patterned closely with word-initial position, supporting the view that the nuclear word is not associated with a distinct phrasing domain

Abstract

In Yukatek Maya, event types are lexicalized in verb roots and stems that fall into a number of different form classes on the basis of (a) patterns of aspect-mood marking and (b) priviledges of undergoing valence-changing operations. Of particular interest are the intransitive classes in the light of Perlmutter’s (1978) Unaccusativity hypothesis. In the spirit of Levin & Rappaport Hovav (1995) [L&RH], Van Valin (1990), Zaenen (1993), and others, this paper investigates whether (and to what extent) the association between formal predicate classes and event types is determined by argument structure features such as ‘agentivity’ and ‘control’ or features of lexical aspect such as ‘telicity’ and ‘durativity’. It is shown that mismatches between agentivity/control and telicity/durativity are even more extensive in Yukatek than they are in English (Abusch 1985; L&RH, Van Valin & LaPolla 1997), providing new evidence against Dowty’s (1979) reconstruction of Vendler’s (1967) ‘time schemata of verbs’ in terms of argument structure configurations. Moreover, contrary to what has been claimed in earlier studies of Yukatek (Krämer & Wunderlich 1999, Lucy 1994), neither agentivity/control nor telicity/durativity turn out to be good predictors of verb class membership. Instead, the patterns of aspect-mood marking prove to be sensitive only to the presence or absense of state change, in a way that supports the unified analysis of all verbs of gradual change proposed by Kennedy & Levin (2001). The presence or absence of ‘internal causation’ (L&RH) may motivate the semantic interpretation of transitivization operations. An explicit semantics for the valence-changing operations is proposed, based on Parsons’s (1990) Neo-Davidsonian approach.

Abstract

This paper introduces the EU-FP7 project CLARIN, a joint effort of over 150 institutions in Europe, aimed at the creation of a sustainable language resources and technology infrastructure for the humanities and social sciences research community. The paper briefly introduces the vision behind the project and how it relates to speech research with a focus on the contributions that CLARIN can and will make to research in spoken language processing.

Abstract

This study explores how adults and children describe placement events (e.g., putting a book on a table) in a range of different languages (Finnish, English, German, Russian, Hindi, Tzeltal Maya, Spanish, and Turkish). Results show that the eight languages grammatically encode placement events in two main ways (Talmy, 1985, 1991), but further investigation reveals fine-grained crosslinguistic variation within each of the two groups. Children are sensitive to these finer-grained characteristics of the input language at an early age, but only when such features are perceptually salient. Our study demonstrates that a unitary notion of 'event' does not suffice to characterize complex but systematic patterns of event encoding crosslinguistically, and that children are sensitive to multiple influences, including the distributional properties of the target language, in constructing these patterns in their own speech.

Abstract

Within the ISLE Metadata Initiative (IMDI) project a user-friendly editor to enter metadata descriptions and a browser operating on the linked metadata descriptions were developed. Both tools support the usage of Controlled Vocabulary (CV) repositories by means of the specification of an URL where the formal CV definition data is available.

Abstract

The recent increase in the number and complexity of the language resources available on the Internet is followed by a similar increase of available tools for linguistic analysis. Ideally the user does not need to be confronted with the question in how to match tools with resources. If resource repositories and tool repositories offer adequate metadata information and a suitable exchange protocol is developed this matching process could be performed (semi-) automatically.

Abstract

Native speakers of Dutch with English as a second language and native speakers of English participated in an English lexical decision experiment. Phonemes in real words were replaced by others from which they are hard to distinguish for Dutch listeners. Non-native listeners judged the resulting near-words more often as a word than native listeners. This not only happened when the phonemes that were exchanged did not exist as separate phonemes in the native language Dutch, but also when phoneme pairs that do exist in Dutch were used in word-final position, where they are not distinctive in Dutch. In an English bimodal priming experiment with similar groups of participants, word pairs were used which differed in one phoneme. These phonemes were hard to distinguish for the non-native listeners. Whereas in native listening both words inhibited each other, in non-native listening presentation of one word led to unresolved competition between both words. The results suggest that inaccurate phoneme processing by non-native listeners leads to the activation of spurious lexical competitors.

Abstract

For multimodal annotations an exhaustive encoding system for gestures was developed to facilitate research. The structural requirements of multimodal annotations were analyzed to develop an Abstract Corpus Model which is the basis for a powerful annotation and exploitation tool for multimedia recordings and the definition of the XML-based EUDICO Annotation Format. Finally, a metadata-based data management environment has been setup to facilitate resource discovery and especially corpus management. Bt means of an appropriate digitization policy and their online availability researchers have been able to build up a large corpus covering gesture and sign language data.

Abstract

Large auditory-visual (AV) speech corpora are the grist of modern research in speech science, but no such corpus exists for Australian English. This is unfortunate, for speech science is the brains behind speech technology and applications such as text-to-speech (TTS) synthesis, automatic speech recognition (ASR), speaker recognition and forensic identification, talking heads, and hearing prostheses. Advances in these research areas in Australia require a large corpus of Australian English. Here the authors describe a blueprint for building the Big Australian Speech Corpus (the Big ASC), a corpus of over 1,100 speakers from urban and rural Australia, including speakers of non-indigenous, indigenous, ethnocultural, and disordered forms of Australian English, each of whom would be sampled on three occasions in a range of speech tasks designed by the researchers who would be using the corpus.

Abstract

According to theories of embodied cognition, understanding a verb like throw involves unconsciously simulating the action throwing, using areas of the brain that support motor planning. If understanding action words involves mentally simulating our own actions, then the neurocognitive representation of word meanings should differ for people with different kinds of bodies, who perform actions in systematically different ways. In a test of the body-specificity hypothesis (Casasanto, 2009), we used fMRI to compare premotor activity correlated with action verb understanding in right- and left-handers. Right-handers preferentially activated left premotor cortex during lexical decision on manual action verbs (compared with non-manual action verbs), whereas left-handers preferentially activated right premotor areas. This finding helps refine theories of embodied semantics, suggesting that implicit mental simulation during language processing is body-specific: Right and left-handers, who perform actions differently, use correspondingly different areas of the brain for representing action verb meanings.

Abstract

What is the relationship between motor action and emotion? Here we investigated whether people associate good things more strongly with the dominant side of their bodies, and bad things with the non-dominant side. To find out, we analyzed spontaneous gestures during speech expressing ideas with positive or negative emotional valence (e.g., freedom, pain, compassion). Samples of speech and gesture were drawn from the 2004 and 2008 US presidential debates, which involved two left-handers (Obama, McCain) and two right-handers (Kerry, Bush). Results showed a strong association between the valence of spoken clauses and the hands used to make spontaneous co-speech gestures. In right-handed candidates, right-hand gestures were more strongly associated with positive-valence clauses, and left-hand gestures with negative-valence clauses. Left-handed candidates showed the opposite pattern. Right- and left-handers implicitly associated positive valence more strongly with their dominant hand: the hand they can use more fluently. These results support the body-specificity hypothesis, (Casasanto, 2009), and suggest a perceptuomotor basis for even our most abstract ideas.

Abstract

What is the relationship between space and time in the human mind? Studies in adults show an asymmetric relationship between mental representations of these basic dimensions of experience: representations of time depend on space more than representations of space depend on time. Here we investigated the relationship between space and time in the developing mind. Native Greek-speaking children (N=99) watched movies of two animals traveling along parallel paths for different distances or durations and judged the spatial and temporal aspects of these events (e.g., Which animal went for a longer time, or a longer distance?) Results showed a reliable cross-dimensional asymmetry: for the same stimuli, spatial information influenced temporal judgments more than temporal information influenced spatial judgments. This pattern was robust to variations in the age of the participants and the type of language used to elicit responses. This finding demonstrates a continuity between space-time representations in children and adults, and informs theories of analog magnitude representation.

Abstract

In this paper we explore the feasibility of artificial (formal) grammar recognition (AGR) using spiking neural networks. A biologically inspired minicolumn architecture is designed as the basic computational unit. A network topography is defined based on the minicolumn architecture, here referred to as nodes, connected with excitatory and inhibitory connections. Nodes in the network represent unique internal states of the grammar’s finite state machine (FSM). Future work to improve the performance of the networks is discussed. The modeling framework developed can be used by neurophysiological research to implement network layouts and compare simulated performance characteristics to actual subject performance.

Abstract

Two groups of listeners with Dutch and British English language backgrounds judged Dutch and British English utterances, respectively, which varied in the intonation contour on the scales EMPHATIC vs. NOT EMPHATIC and SURPRISED vs. NOT SURPRISED, two meanings derived from the Effort Code. The stimuli, which differed in sentence mode but were otherwise lexically equivalent, were varied in peak height, peak alignment, end pitch, and overall register. In both languages, there are positive correlations between peak height and degree of emphasis, between peak height and degree of surprise, between peak alignment and degree of surprise, and between pitch register and degree of surprise. However, in all these cases, Dutch stimuli lead to larger perceived meaning differences than the British English stimuli. This difference in the extent to which increased pitch height triggers increases in perceived emphasis and surprise is argued to be due to the difference in the standard pitch ranges between Dutch and British English. In addition, we found a positive correlation between pitch register and the degree of emphasis in Dutch, but a negative correlation in British English. This is an unexpected difference, which illustrates a case of ambiguity in the meaning of pitch.

Abstract

We investigated how listeners of two unrelated languages, Dutch and Korean, process phonotactically legitimate and illegitimate sounds spoken in Dutch and American English. To Dutch listeners, unreleased word-final stops are phonotactically illegal because word-final stops in Dutch are generally released in isolation, but to Korean listeners, released final stops are illegal because word-final stops are never released in Korean. Two phoneme monitoring experiments showed a phonotactic effect: Dutch listeners detected released stops more rapidly than unreleased stops whereas the reverse was true for Korean listeners. Korean listeners with English stimuli detected released stops more accurately than unreleased stops, however, suggesting that acoustic-phonetic cues associated with released stops improve detection accuracy. We propose that in non-native speech perception, phonotactic legitimacy in the native language speeds up phoneme recognition, the richness of acousticphonetic cues improves listening accuracy, and familiarity with the non-native language modulates the relative influence of these two factors.

Abstract

The aim of this study was to determine if Dutch speakers reliably signal phrase-internal lexical boundaries, and if so, how. Six speakers recorded 4 pairs of phonemically identical strong-weak-strong (SWS) strings with matching syllable boundaries but mismatching intended word boundaries (e.g. reis # pastei versus reispas # tij, or more broadly C1V2(C)#C2V2(C)C3V3(C) vs. C1V2(C)C2V2(C)#C3V3(C)). An Analysis of Variance revealed 3 acoustic parameters that were significantly greater in S#WS items (C2 DURATION, RIME1 DURATION, C3 BURST AMPLITUDE) and 5 parameters that were significantly greater in the SW#S items (C2 VOT, C3 DURATION, RIME2 DURATION, RIME3 DURATION, and V2 AMPLITUDE). Additionally, center of gravity measurements suggested that the [s] to [t] coarticulation was greater in reis # pa[st]ei versus reispa[s] # [t]ij. Finally, a Logistic Regression Analysis revealed that the 3 parameters (RIME1 DURATION, RIME2 DURATION, and C3 DURATION) contributed most reliably to a S#WS versus SW#S classification.

Abstract

The fluent production of speech is a very complex human skill. It requires the coordination of several articulatory subsystems. The instructions that lead articulatory movements to execution are the result of the interplay of speech production levels that operate above the articulatory network. During the process of word-form encoding, the groundwork for the articulatory programs is prepared which then serve the articulators as basic units. This thesis investigated whether or not syllables form the basis for the articulatory programs and in particular whether or not these syllable programs are stored, separate from the store of the lexical word-forms. It is assumed that syllable units are stored in a so-called 'mental syllabary'. The main goal of this thesis was to find evidence of the syllable playing a functionally important role in speech production and for the assumption that syllables are stored units. In a variant of the implicit priming paradigm, it was investigated whether information about the syllabic structure of a target word facilitates the preparation (advanced planning) of a to-be-produced utterance. These experiments yielded evidence for the functionally important role of syllables in speech production. In a subsequent row of experiments, it could be demonstrated that the production of syllables is sensitive to frequency. Syllable frequency effects provide strong evidence for the notion of a mental syllabary because only stored units are likely to exhibit frequency effects. In a last study, effects of syllable preparation and syllable frequency were investigated in a combined study to disentangle the two effects. The results of this last experiment converged with those reported for the other experiments and added further support to the claim that syllables play a core functional role in speech production and are stored in a mental syllabary.

Abstract

When we speak, we spontaneously produce gestures (co-speech gestures). Co-speech gestures and speech production are closely interlinked. However, the exact nature of the link is still under debate. To addressed the question that whether co-speech gestures originate from the speech production system or from a system independent of the speech production, the present study examined the relationship between co-speech and co-thought gestures. Co-thought gestures, produced during silent thinking without speaking, presumably originate from a system independent of the speech production processes. We found a positive correlation between the production frequency of co-thought and co-speech gestures, regardless the communicative function that co-speech gestures might serve. Therefore, we suggest that co-speech gestures and co-thought gestures originate from a common system that is independent of the speech production processes

Abstract

We report an investigation of the perception of American English phonemes by Dutch listeners proficient in English. Listeners identified either the consonant or the vowel in most possible English CV and VC syllables. The syllables were embedded in multispeaker babble at three signal-to-noise ratios (16 dB, 8 dB, and 0 dB). Effects of signal-to-noise ratio on vowel and consonant identification are discussed as a function of syllable position and of relationship to the native phoneme inventory. Comparison of the results with previously reported data from native listeners reveals that noise affected the responding of native and non-native listeners similarly.

Abstract

In this study, we compared the performance of a long short-term memory (LSTM) neural network to the behavior of human participants on a language task that requires hierarchically structured knowledge. We show that humans interpret ambiguous noun phrases, such as second blue ball, in line with their hierarchical constituent structure. LSTMs, instead, only do
so after unambiguous training, and they do not systematically generalize to novel items. Overall, the results of our simulations indicate that a model can behave hierarchically without relying on hierarchical constituent structure.

Abstract

Language-specific differences in the size and distribution of the phonemic repertoire can have implications for the task facing listeners in recognising spoken words. A language with more phonemes will allow shorter words and reduced embedding of short words within longer ones, decreasing the potential for spurious lexical competitors to be activated by speech signals. We demonstrate that this is the case via comparative analyses of the vocabularies of English and Spanish. A language which uses suprasegmental as well as segmental contrasts, however, can substantially reduce the extent of spurious embedding.

Abstract

The Possible Word Constraint is a proposed mechanism whereby listeners avoid recognising words spuriously embedded in other words. It applies to words leaving a vowelless residue between their edge and the nearest known word or syllable boundary. The present study tests the usefulness of this constraint via lexical statistics of both English and Dutch. The analyses demonstrate that the constraint removes a clear majority of embedded words in speech, and thus can contribute significantly to the efficiency of human speech recognition

Abstract

Assimilation of place of articulation across a nasal and a following stop consonant is obligatory in Japanese, but not in Dutch. In four experiments the processing of assimilated forms by speakers of Japanese and Dutch was compared, using a task in which listeners blended pseudo-word pairs such as ranga-serupa. An assimilated blend of this pair would be rampa, an unassimilated blend rangpa. Japanese listeners produced significantly more assimilated than unassimilated forms, both with pseudo-Japanese and pseudo-Dutch materials, while Dutch listeners produced significantly more unassimilated than assimilated forms in each materials set. This suggests that Japanese listeners, whose native-language phonology involves obligatory assimilation constraints, represent the assimilated nasals in nasal-stop sequences as unmarked for place of articulation, while Dutch listeners, who are accustomed to hearing unassimilated forms, represent the same nasal segments as marked for place of articulation.

Abstract

Languages contain tens of thousands of words, but these are constructed from a tiny handful of phonetic elements. Consequently, words resemble one another, or can be embedded within one another, a coup stick snot with standing. me process of spoken-word recognition by human listeners involves activation of multiple word candidates consistent with the input, and direct competition between activated candidate words. Further, human listeners are sensitive, at an early, prelexical, stage of speeeh processing, to constraints on what could potentially be a word of the language.

Abstract

Two phoneme goodness rating experiments addressed the role of orthographic knowledge in the evaluation of speech sounds. Ratings for the best tokens of /s/ were higher in words spelled with S (e.g., bless) than in words where /s/ was spelled with C (e.g., voice). This difference did not appear for analogous nonwords for which every lexical neighbour had either S or C spelling (pless, floice). Models of phonemic processing incorporating obligatory influence of lexical information in phonemic processing cannot explain this dissociation; the data are consistent with models in which phonemic decisions are not subject to necessary top-down lexical influence.

Abstract

The phoneme detection task is widely used in spoken word recognition research. Alphabetically literate participants, however, are more used to explicit representations of letters than of phonemes. The present study explored whether phoneme detection is sensitive to how target phonemes are, or may be, orthographically realised. Listeners detected the target sounds [b,m,t,f,s,k] in word-initial position in sequences of isolated English words. Response times were faster to the targets [b,m,t], which have consistent word-initial spelling, than to the targets [f,s,k], which are inconsistently spelled, but only when listeners’ attention was drawn to spelling by the presence in the experiment of many irregularly spelled fillers. Within the inconsistent targets [f,s,k], there was no significant difference between responses to targets in words with majority and minority spellings. We conclude that performance in the phoneme detection task is not necessarily sensitive to orthographic effects, but that salient orthographic manipulation can induce such sensitivity.

Abstract

In a production experiment on Bulgarian that was based on a previous study on Dutch [1], we investigated the role of prosody when linguistic and extra-linguistic information coincide or contradict. Speakers described abnormally colored fruits in conditions where contrastive focus and discourse relations were varied. We found that the coincidence of contrast and abnormality enhances accentuation in Bulgarian as it did in Dutch. Surprisingly, when both factors are in conflict, the prosodic prominence of abnormality often overruled focus accentuation in both Bulgarian and Dutch, though the languages also show marked differences.

Abstract

This paper summarizes the results of a descriptive syntactic category analysis of child English no which reveals that young children use and represent no as a determiner and negatives like no pen as NPs, contra standard analyses.

Abstract

This paper investigates how listeners process regular pronunciation variants, resulting from simple general reduction processes. Study 1 shows that when listeners are presented with new words, they store the pronunciation variants presented to them, whether these are unreduced or reduced. Listeners thus store information on word-specific pronunciation variation. Study 2 suggests that if participants are presented with regularly reduced pronunciations, they also reconstruct and store the corresponding unreduced pronunciations. These unreduced pronunciations apparently have special status. Together the results support hybrid models of speech processing, assuming roles for both exemplars and abstract representations.

Abstract

Anaphora, a ubiquitous feature of natural language, poses a particular challenge to young children as they first learn language due to its referential ambiguity. In spite of this, parents and caregivers use anaphora frequently in child-directed speech, potentially presenting a risk to effective communication if children do not yet have the linguistic capabilities of resolving anaphora successfully. Through an eye-tracking study in a naturalistic free-play context, we examine the strategies that parents employ to calibrate their use of anaphora to their child's linguistic development level. We show that, in this way, parents are able to intuitively scaffold the complexity of their speech such that greater referential ambiguity does not hurt overall communication success.

Abstract

Children learn their mother tongue spontaneously and effortlessly through communicative interaction with their environment; they do not have to be taught explicitly or learn how to learn first. The ambient language to which children are exposed, however, is highly variable and arguably deficient with regard to the learning target. Nonetheless, most normally developing children learn their native language rapidly and with ease. To explain this accomplishment, many theories of acquisition posit innate constraints on learning, or even a biological endowment for language which is specific to language. Usage-based theories, on the other hand, place more emphasis on the role of experience and domain-general learning mechanisms than on innate language-specific knowledge. But languages are lexically open and combinatorial in structure, so no amount of experience covers their expressivity. Usage-based theories therefore have to explain how children can generalize the properties of their linguistic input to an adult-like grammar. In this thesis I provide an explicit computational mechanism with which usage-based theories of language can be tested and evaluated. The focus of my work lies on complex syntax and the human ability to form sentences which express more than one proposition by means of relativization. This `capacity for recursion' is a hallmark of an adult grammar and, as some have argued, the human language faculty itself. The manuscript is organized as follows. In the second chapter, I give an overview of results that characterize the properties of neural networks as mathematical objects and review previous attempts at modelling the acquisition of complex syntax with such networks. The chapter introduces the conceptual landscape in which the current work is located. In the third chapter, I argue that the construction and use of meaning is essential in child language acquisition and adult processing. Neural network models need to incorporate this dimension of human linguistic behavior. I introduce the Dual-path model of sentence production and syntactic development which is able to represent semantics and learns from exposure to sentences paired with their meaning (cf. Chang et al. 2006). I explain the architecture of this model, motivate critical assumptions behind its design, and discuss existing research using this model. The fourth chapter describes and compares several extensions of the basic architecture to accommodate the processing of multi-clause utterances. These extensions are evaluated against computational desiderata, such as good learning and generalization performance and the parsimony of input representations. A single-best solution for encoding the meaning of complex sentences with restrictive relative clauses is identified, which forms the basis for all subsequent simulations. Chapter five analyzes the learning dynamics in more detail. I first examine the model's behavior for different relative clause types. Syntactic alternations prove to be particularly difficult to learn because they complicate the meaning-to-form mapping the model has to acquire. In the second part, I probe the internal representations the model has developed during learning. It is argued that the model acquires the argument structure of the construction types in its input language and represents the hierarchical organization of distinct multi-clause utterances. The juice of this thesis is contained in chapters six to eight. In chapter six, I test the Dual-path model's generalization capacities in a variety of tasks. I show that its syntactic representations are sufficiently transparent to allow structural generalization to novel complex utterances. Semantic similarities between novel and familiar sentence types play a critical role in this task. The Dual-path model also has a capacity for generalizing familiar words to novel slots in novel constructions (strong semantic systematicity). Moreover, I identify learning conditions under which the model displays recursive productivity. It is argued that the model's behavior is consistent with human behavior in that production accuracy degrades with depth of embedding, and right-branching is learned faster than center-embedding recursion. In chapter seven, I address the issue of learning complex polar interrogatives in the absence of positive exemplars in the input. I show that the Dual-path model can acquire the syntax of these questions from simpler and similar structures which are warranted in a child's linguistic environment. The model's errors closely match children's errors, and it is suggested that children might not require an innate learning bias to acquire auxiliary fronting. Since the model does not implement a traditional kind of language-specific universal grammar, these results are relevant to the poverty of the stimulus debate. English relative clause constructions give rise to similar performance orderings in adult processing and child language acquisition. This pattern matches the typological universal called the noun phrase accessibility hierarchy. I propose an input-based explanation of this data in chapter eight. The Dual-path model displays this ordering in syntactic development when exposed to plausible input distributions. But it is possible to manipulate and completely remove the ordering by varying properties of the input from which the model learns. This indicates, I argue, that patterns of interference and facilitation among input structures can explain the hierarchy when all structures are simultaneously learned and represented over a single set of connection weights. Finally, I draw conclusions from this work, address some unanswered questions, and give a brief outlook on how this research might be continued.

Abstract

We present a neural-symbolic learning model of sentence production which displays strong semantic systematicity and recursive productivity. Using this model, we provide evidence for the data-driven learnability of complex yes/no- questions.

Abstract

Los idiomas sudamericanas tienen una diversidad de sistemas numéricos, desde sistemas con solamente dos o tres términos en algunos idiomas amazónicos hasta sistemas con numerales extendiendo a miles. Una mirada al sistema del idioma cha’palaa de Ecuador demuestra rasgos de base-2, base-5, base-10 y base-20, ligados a diferentes etapas de cambio, desarrollo y contacto lingüístico. Conocer estas etapas nos permite proponer algunas correlaciones con lo que conocemos de la historia de contactos culturales en la región. The South American languages have diverse types of numeral systems, from systems of just two or three terms in some Amazonian languages to systems extending into the thousands. A look a the system of the Cha'palaa language of Ecuador demonstrates base-2, base-5, base-10 and base-20 features, linked to different stages of change, development and language contact. Learning about these stages permits up to propose some correlations between them and what we know about the history of cultural contact in the region.

Abstract

In a 2x2 event-related FMRI study we find support for the idea that the inferior frontal cortex, centered on Broca’s region and its homologue, is involved in constructive unification operations during the structure-building process in parsing for comprehension. Tentatively, we provide evidence for a role of the dorsolateral prefrontal cortex centered on BA 9/46 in the control component of the language system. Finally, the left temporo-parietal cortex, in the vicinity of Wernicke’s region, supports the interaction between the syntax of gender agreement and sentence-level semantics.

Abstract

Human implicit learning can be investigated with implicit artificial grammar learning, a simple model for aspects of natural language acquisition. In this paper we investigate the remaining effect of modality transfer in syntactic classification of an acquired grammatical sequence structure after implicit grammar acquisition. Participants practiced either on acoustically presented syllable sequences or visually presented consonant letter sequences. During classification we independently manipulated the statistical frequency-based and rule-based characteristics of the classification stimuli. Participants performed reliably above chance on the within modality classification task although more so for those working on syllable sequence acquisition. These subjects were also the only group that kept a significant performance level in transfer classification. We speculate that this finding is of particular relevance in consideration of an ecological validity in the input signal in the use of artificial grammar learning and in language learning paradigms at large.

Abstract

As knowing a foreign language becomes a necessity in the modern world, a large portion of
the population is faced with the challenge of learning a language in a classroom. This, in turn,
presents a unique set of difficulties. Acquiring a language with limited and artificial exposure makes
learning new information and vocabulary particularly difficult. The purpose of this thesis is to help us
understand how we can compensate—at least partially—for these difficulties by presenting
information in a way that aids learning. In particular, I focused on variables that affect semantic
richness—meaning the amount and variability of information associated with a word. Some factors
that affect semantic richness are intrinsic to the word and others pertain to that word’s relationship
with other items and information. This latter group depends on the context around the to-be-
learned items rather than the words themselves. These variables are easier to manipulate than
intrinsic qualities, making them more accessible tools for teaching and understanding learning. I
focused on two factors: emotionality of the surrounding semantic context and contextual diversity.
Publication 1 (Frances, de Bruin, et al., 2020b) focused on content learning in a foreign
language and whether the emotionality—positive or neutral—of the semantic context surrounding
key information aided its learning. This built on prior research that showed a reduction in
emotionality in a foreign language. Participants were taught information embedded in either
positive or neutral semantic contexts in either their native or foreign language. When they were
then tested on these embedded facts, participants’ performance decreased in the foreign language.
But, more importantly, they remembered better the information from the positive than the neutral
semantic contexts.
In Publication 2 (Frances, de Bruin, et al., 2020a), I focused on how emotionality affected
vocabulary learning. I taught participants the names of novel items described either in positive or
neutral terms in either their native or foreign language. Participants were then asked to recall and
recognize the object's name—when cued with its image. The effects of language varied with the
difficulty of the task—appearing in recall but not recognition tasks. Most importantly, learning the
words in a positive context improved learning, particularly of the association between the image of
the object and its name.
In Publication 3 (Frances, Martin, et al., 2020), I explored the effects of contextual
diversity—namely, the number of texts a word appears in—on native and foreign language word
learning. Participants read several texts that had novel pseudowords. The total number of
encounters with the novel words was held constant, but they appeared in 1, 2, 4, or 8 texts in either
their native or foreign language. Increasing contextual diversity—i.e., the number of texts a word
appeared in—improved recall and recognition, as well as the ability to match the word with its
meaning. Using a foreign language only affected performance when participants had to quickly
identify the meaning of the word.
Overall, I found that the tested contextual factors related to semantic richness—i.e.,
emotionality of the semantic context and contextual diversity—can be manipulated to improve
learning in a foreign language. Using positive emotionality not only improved learning in the foreign
language, but it did so to the same extent as in the native language. On a theoretical level, this
suggests that the reduction in emotionality in a foreign language is not ubiquitous and might relate
to the way in which that language as learned.
The third article shows an experimental manipulation of contextual diversity and how this
can affect learning of a lexical item, even if the amount of information known about the item is kept
constant. As in the case of emotionality, the effects of contextual diversity were also the same
between languages. Although deducing words from context is dependent on vocabulary size, this
does not seem to hinder the benefits of contextual diversity in the foreign language.
Finally, as a whole, the articles contained in this compendium provide evidence that some
aspects of semantic richness can be manipulated contextually to improve learning and memory. In
addition, the effects of these factors seem to be independent of language status—meaning, native
or foreign—when learning new content. This suggests that learning in a foreign and a native
language is not as different as I initially hypothesized, allowing us to take advantage of native
language learning tools in the foreign language, as well.

Abstract

Graph neural networks (GNNs) have emerged as the standard method for numerous tasks on graph-structured data such as node classification. However, real-world graphs are often evolving over time and even new classes may arise. We model these challenges as an instance of lifelong learning, in which a learner faces a sequence of tasks and may take over knowledge acquired in past tasks. Such knowledge may be stored explicitly as historic data or implicitly within model parameters. In this work, we systematically analyze the influence of implicit and explicit knowledge. Therefore, we present an incremental training method for lifelong learning on graphs and introduce a new measure based on k-neighborhood time differences to address variances in the historic data. We apply our training method to five representative GNN architectures and evaluate them on three new lifelong node classification datasets. Our results show that no more than 50% of the GNN's receptive field is necessary to retain at least 95% accuracy compared to training over the complete history of the graph data. Furthermore, our experiments confirm that implicit knowledge becomes more important when fewer explicit knowledge is available.

Abstract

COVID-19 research datasets are crucial for analyzing research dynamics. Most collections of COVID-19 research items do not to include cited works and do not have annotations
from a controlled vocabulary. Starting with ZB MED KE data on COVID-19, which comprises CORD-19, we assemble a new dataset that includes cited work and MeSH annotations for all records. Furthermore, we conduct experiments on the analysis of research dynamics, in which we investigate predicting links in a co-annotation graph created on the basis of the new dataset. Surprisingly, we find that simple heuristic methods are better at
predicting future links than more sophisticated approaches such as graph neural networks.

Abstract

This paper presents a new architecture for optical burst switched networks where the control plane of the network functions in a cooperative manner. Each node interprets the data conveyed by the control packet and forwards it to the next nodes, making the control plane of the network distribute the relevant information to all the nodes in the network. A cooperation transmission tree is used, thus allowing all the nodes to store the information related to the traffic management in the network, and enabling better network resource planning at each node. A model of this network architecture is proposed, and its performance is evaluated.

Abstract

In this paper we introduce Functional Data Analysis (FDA) as a tool for analyzing dynamic transitions in speech signals. FDA makes it possible to perform statistical analyses of sets of mathematical functions in the same way as classical multivariate analysis treats scalar measurement data. We illustrate the use of FDA with a reduction phenomenon affecting the French word c'était /setε/ 'it was', which can be reduced to [stε] in conversational speech. FDA reveals that the dynamics of the transition from [s] to [t] in fully reduced cases may still be different from the dynamics of [s] - [t] transitions in underlying /st/ clusters such as in the word stage.

Abstract

Trumai, a genetically isolated language spoken in Brazil (Xingu reserve), is an example of an endangered language. Although the Trumai population consists of more than 100 individuals, only 51 people speak the language. The oral traditions are progressively dying. Given the current scenario, the documentation of this language and its cultural aspects is of great importance. In the framework of the DoBeS program (Documentation of Endangered Languages), the project "Documentation of Trumai" has selected and organized a collection of Trumai texts, with a multi-media representation of the corpus. Several kinds of information and data types are being included in the archive of the language: texts with audio and video recordings; written texts from educational materials; drawings; photos; songs; annotations in different formats; lexicon; field notes; results from scientific studies of the language (sound system, sketch grammar, comparative studies with other Xinguan languages), etc. All materials are integrated into the IMDI-Browser, a specialized tool for presenting and searching for linguistic data. This paper explores the processing phases and the results of the Trumai project taking into consideration the issue of how to combine the needs and wishes of field linguistics (content and research aspects) and the needs of archiving (structure and workflow aspects) in a well-organized corpus.

Abstract

A prototypical lexicon tool was implemented which was intended to allow researchers to collaboratively create lexicons of endangered languages. Increasingly often researchers documenting or analyzing a language work at different locations. Lexicons that evolve through continuous interaction between the collaborators can only be efficiently produced when it can be accessed and manipulated via the Internet. The SHAWEL tool was developed to address these needs; it makes use of a thin Java client and a central database solution.

Abstract

Whitesands is an under-described language of southern Vanuatu, and this thesis presents Whitesands-specific data based on primary in-situ field research. The thesis addresses the distinction of noun and verb word classes in the language. It claims that current linguistic syntax theory cannot account for the argument structure of canonical object-denoting roots. It is shown that there are distinct lexical noun and verb classes in Whitesands but this is only a weak dichotomy. Stronger is the NP and VP distinction, and this is achieved by employing a new theoretical approach that proposes functional categories and their selection of complements as crucial tests of distinction. This approach contrasts with previous analyses of parts of speech in Oceanic languages and cross-linguistically. It ultimately explains many of the syntactic phenomena seen in the language family, including the above argument assignment dilemma, the alienable possession of nouns with classifiers and also the nominalisation processes.

Abstract

We present a quantitative model of word order and movement constraints that enables a simple and uniform treatment of a seemingly heterogeneous collection of linear order phenomena in English, Dutch and German complement constructions (Wh-extraction, clause union, extraposition, verb clustering, particle movement, etc.). Underlying the scheme are central assumptions of the psycholinguistically motivated Performance Grammar (PG). Here we describe this formalism in declarative terms based on typed feature unification. PG allows a homogenous treatment of both the within- and between-language variations of the ordering phenomena under discussion, which reduce to different settings of a small number of quantitative parameters.

Abstract

Present-day sentence generators are often in-capable of producing a wide variety of well-formed elliptical versions of coordinated clauses, in particular, of combined elliptical phenomena (Gapping, Forward and Back-ward Conjunction Reduction, etc.). The ap-plicability of the various types of clausal co-ordinate ellipsis (CCE) presupposes detailed comparisons of the syntactic properties of the coordinated clauses. These nonlocal comparisons argue against approaches based on local rules that treat CCE structures as special cases of clausal coordination. We advocate an alternative approach where CCE rules take the form of postediting rules ap-plicable to nonelliptical structures. The ad-vantage is not only a higher level of modu-larity but also applicability to languages be-longing to different language families. We describe a language-neutral module (called Elleipo; implemented in JAVA) that gener-ates as output all major CCE versions of co-ordinated clauses. Elleipo takes as input linearly ordered nonelliptical coordinated clauses annotated with lexical identity and coreferentiality relationships between words and word groups in the conjuncts. We dem-onstrate the feasibility of a single set of postediting rules that attains multilingual coverage.

Abstract

Children with developmental language disorder (DLD) regularly use the base form of verbs (e.g., dance) instead of inflected forms (e.g., danced). We propose an account of this behavior in which children with DLD have difficulty processing novel inflected verbs in their input. This leads the inflected form to face stronger competition from alternatives. Competition is resolved by the production of a more accessible alternative with high semantic overlap with the inflected form: in English, the bare form. We test our account computationally by training a nonparametric Bayesian model that infers the productivity of the inflectional suffix (-ed). We systematically vary the number of novel types of inflected verbs in the input to simulate the input as processed by children with and without DLD. Modeling results are consistent with our hypothesis, suggesting that children’s inconsistent use of inflectional morphemes could stem from inferences they make on the basis of impoverished data.

Abstract

Using the visual-word paradigm, the present study investigated the effects of word onset and offset masking on the time course of non-native spoken-word recognition in the presence of background noise. In two experiments, Dutch non-native listeners heard English target words, preceded by carrier sentences that were noise-free (Experiment 1) or contained intermittent noise (Experiment 2). Target words were either onset- or offset-masked or not masked at all. Results showed that onset masking delayed target word recognition more than offset masking did, suggesting that – similar to natives – non-native listeners strongly rely on word onset information during word recognition in noise.