Publications

Abstract

This study investigates neighbourhood density effects on lexical decision performance (both accuracy and response times) of aphasic patients. Given earlier results on lexical activation and deactivation in Broca's and Wernicke's aphasia, the prediction was that smaller neighbourhood density effects would be found for Broca's aphasic patients, compared to age-matched non-brain-damaged control participants, whereas enlarged density effects were expected for Wernicke's aphasic patients. The results showed density effects for all three groups of listeners, and overall differences in performance between groups, but no significant interaction between neighbourhood density and listener group. Several factors are discussed to account for the present results.

Abstract

This study investigates the relative contributions of auditory and cognitive factors to the common finding that an increase in speech rate affects elderly listeners more than young listeners. Since a direct relation between non-auditory factors, such as age-related cognitive slowing, and fast speech performance has been difficult to demonstrate, the present study took an on-line, rather than off-line, approach and focused on processing time. Elderly and young listeners were presented with speech at two rates of time compression and were asked to detect pre-assigned target words as quickly as possible. A number of auditory and cognitive measures were entered in a statistical model as predictors of elderly participants’ fast speech performance: hearing acuity, an information processing rate measure, and two measures of reading speed. The results showed that hearing loss played a primary role in explaining elderly listeners’ increased difficulty with fast speech. However, non-auditory factors such as reading speed and the extent to which participants were affected by
increased rate of presentation in a visual analog of the listening experiment also predicted fast
speech performance differences among the elderly participants. These on-line results confirm that slowed information processing is indeed part of elderly listeners’ problem keeping up with fast language

Abstract

Natural fast speech differs from normal-rate speech with respect to its temporal pattern. Previous results showed that word intelligibility of heavily artificially time-compressed speech could not be improved by making its temporal pattern more similar to that of natural fast speech. This might have been due to the extrapolation of timing rules for natural fast speech to rates that are much faster than can be attained by human speakers. The present study investigates whether, at a speech rate that human speakers can attain, artificially time-compressed speech is easier to process if its timing pattern is similar to that of naturally produced fast speech. Our first experiment suggests, however, that word processing speed was slowed down, relative to linear compression. In a second experiment, word processing of artificially time-compressed speech was compared with processing of naturally produced fast speech. Even when naturally produced fast speech is perfectly intelligible, its less careful articulation, combined with the changed timing pattern, slows down processing, relative to linearly time-compressed speech. Furthermore, listeners preferred artificially time-compressed speech over naturally produced fast speech. These results suggest that linearly time-compressed speech has both a temporal and a segmental advantage over natural fast speech.

Abstract

This study investigated the encoding of syllable boundary information during speech production in Dutch. Based on Levelt's model of phonological encoding, we hypothesized segments and syllable boundaries to be encoded in an incremental way. In a selfmonitoring experiment, decisions about the syllable affiliation (first or second syllable) of a pre-specified consonant, which was the third phoneme in a word, were required (e.g., ka.No canoe vs. kaN.sel pulpit ; capital letters indicate pivotal consonants, dots mark syllable boundaries). First syllable responses were faster than second syllable responses, indicating the incremental nature of segmental encoding and syllabification during speech production planning. The results of the experiment are discussed in the context of Levelt 's model of phonological encoding.

Abstract

Three experiments are reported that examined whether stem complexity plays a role in inflecting polymorphemic words in language production. Experiment 1 showed that preparation effects for words with polymorphemic stems are larger when they are produced among words with constant inflectional structures compared to words with variable inflectional structures and simple stems. This replicates earlier findings for words with monomorphemic stems (Janssen et al., 2002). Experiments 2 and 3 showed that when inflectional structure is held constant, the preparation effects are equally large with simple and compound stems, and with compound and complex adjectival stems. These results indicate that inflectional encoding is blind to the complexity of the stem, which suggests that specific inflectional rather than generic morphological frames guide the generation of inflected forms in speaking words.

Abstract

As people find their way through their environment, objects at navigationally relevant locations can serve as crucial landmarks. The parahippocampal gyrus has previously been shown to be involved in object and scene recognition. In the present study, we investigated the neural representation of navigationally relevant locations. Healthy human adults viewed a route through a virtual museum with objects placed at intersections (decision points) or at simple turns (non-decision points). Event-related functional magnetic resonance imaging (fMRI) data were acquired during subsequent recognition of the objects in isolation. Neural activity in the parahippocampal gyrus reflected the navigational relevance of an object's location in the museum. Parahippocampal responses were selectively increased for objects that occurred at decision points, independent of attentional demands. This increase occurred for forgotten as well as remembered objects, showing implicit retrieval of navigational information. The automatic storage of relevant object location in the parahippocampal gyrus provides a part of the neural mechanism underlying successful navigation.

Abstract

The authors compared sublexical and supralexical approaches to morphological processing with unambiguous and ambiguous inflected words and words with ambiguous stems in 3 masked and unmasked priming experiments in Finnish. Experiment 1 showed equal facilitation for all prime types with a short 60-ms stimulus onset asynchrony (SOA) but significant facilitation for unambiguous words only with a long 300-ms SOA. Experiment 2 showed that all potential readings of ambiguous inflections were activated under a short SOA. Whereas the prime-target form overlap did not affect the results under a short SOA, it significantly modulated the results with a long SOA. Experiment 3 confirmed that the results from masked priming were modulated by the morphological structure of the words but not by the prime-target form overlap alone. The results support approaches in which early prelexical morphological processing is driven by morph-based segmentation and form is used to cue selection between 2 candidates only during later processing.

Abstract

Listening to a speaker while hearing another speaker talks is a challenging task for elderly listeners. We show that elderly listeners over the age of 65 with various degrees of age-related hearing loss benefit in this situation from also seeing the speaker they intend to listen to. In a phoneme monitoring task, listeners monitored the speech of a target speaker for either the phoneme /p/ or /k/ while simultaneously hearing a competing speaker. Critically, on some trials, the target speaker was also visible. Elderly listeners benefited in their response times and accuracy levels from seeing the target speaker when monitoring for the less visible /k/, but more so when monitoring for the highly visible /p/. Visual speech therefore aids elderly listeners not only by providing segmental information about the target phoneme, but also by providing more global information that allows for better performance in this adverse listening situation.

Abstract

Mutations of the epidermal growth factor receptor (EGFR) gene are found at a relatively high frequency in glioma, with the most common being the de2-7 EGFR (or EGFRvIII). This mutation arises from an in-frame deletion of exons 2-7, which removes 267 amino acids from the extracellular domain of the receptor. Despite being unable to bind ligand, the de2-7 EGFR is constitutively active at a low level. Transfection of human glioma cells with the de2-7 EGFR has little effect in vitro, but when grown as tumor xenografts this mutated receptor imparts a dramatic growth advantage. We mapped the phosphorylation pattern of de2-7 EGFR, both in vivo and in vitro, using a panel of antibodies specific for different phosphorylated tyrosine residues. Phosphorylation of de2-7 EGFR was detected constitutively at all tyrosine sites surveyed in vitro and in vivo, including tyrosine 845, a known target in the wild-type EGFR for src kinase. There was a substantial upregulation of phosphorylation at every yrosine residue of the de2-7 EGFR when cells were grown in vivo compared to the receptor isolated from cells cultured in vitro. Upregulation of phosphorylation at tyrosine 845 could be stimulated in vitro by the addition of specific components of the ECM via an integrindependent mechanism. These observations may partially explain why the growth enhancement mediated by de2-7 EGFR is largely restricted to the in vivo environment

Abstract

English-learning 7.5-month-olds are heavily biased to perceive stressed syllables as word onsets. By 11 months, however, infants begin segmenting non-initially stressed words from speech.Using the same artificial language methodology as Johnson and Jusczyk (2001), we explored the possibility that the emergence of this ability is linked to a decreased reliance on prosodic cues to word boundaries accompanied by an increased reliance on syllable distribution cues. In a baseline study, where only statistical cues to word boundaries were present, infants exhibited a familiarity preference for statistical words. When conflicting stress cues were added to the speech stream, infants exhibited a familiarity preference for stress as opposed to statistical words. This was interpreted as evidence that 11-month-olds weight stress cues to word boundaries more heavily than statistical cues. Experiment 2 further investigated these results with a language containing convergent cues to word boundaries. The results of Experiment 2 were not conclusive. A third experiment using new stimuli and a different experimental design supported the conclusion that 11-month-olds rely more heavily on prosodic than statistical cues to word boundaries. We conclude that the emergence of the ability to segment non-initially stressed words from speech is not likely to be tied to an increased reliance on syllable distribution cues relative to stress cues, but instead may emerge due to an increased reliance on and integration of a broad array of segmentation cues.

Abstract

The nature of social life in human prehistory is elusive, yet knowing how kinship systems evolve is critical for understanding population history and cultural diversity. Post-marital residence rules specify sex-specific dispersal and kin association, influencing the pattern of genetic markers across populations. Cultural phylogenetics allows us to practise 'virtual archaeology' on these aspects of social life that leave no trace in the archaeological record. Here we show that early Austronesian societies practised matrilocal post-marital residence. Using a Markov-chain Monte Carlo comparative method implemented in a Bayesian phylogenetic framework, we estimated the type of residence at each ancestral node in a sample of Austronesian language trees spanning 135 Pacific societies. Matrilocal residence has been hypothesized for proto-Oceanic society (ca 3500 BP), but we find strong evidence that matrilocality was predominant in earlier Austronesian societies ca 5000-4500 BP, at the root of the language family and its early branches. Our results illuminate the divergent patterns of mtDNA and Y-chromosome markers seen in the Pacific. The analysis of present-day cross-cultural data in this way allows us to directly address cultural evolutionary and life-history processes in prehistory.

Abstract

In early Dutch learner varieties, there is no evidence of finiteness being a functional category. There is no V2nd: no correlation between inflectional morphology and movement. Initially, learners express the illocutive function of finiteness through the use of illocutive markers, with the non-use of an illocutive marker expressing the default illocutive function of assertion. Illocutive markers are functioning as adjuncts with scope over the predicate. Illocutive markers become re-analysed as functional elements.The driving force is the acquisition of the auxiliary verbs that occur with past participles. It leads to a reanalysis of illocutive markers as two separate elements: an auxiliary verb and a scope adverb. The (modal) auxiliary carries illocutive function. Lexical verb-argument structure (including the external argument) occurs within the domain of the auxiliary verb. The predicate as the focus constituent occurs within the domain of a scope adverb. This reanalysis establishes a position for the external argument within the domain of AUX. The acquisition of AUX causes the acquisition of a (hierarchical) structure with a complement as a constituent which represents an underlying verb-argument structure, a predicate as the domain of elements that are in focus, and an external (specifier) position as a landing site for elements with topic function.

Abstract

It is an important feature of the human sentence production system that semantic and syntactic processes may overlap in time and do not proceed strictly serially. That is, the process of building the syntactic form of an utterance does not always wait until the complete semantic content for that utterance has been decided upon. On the contrary, speakers will often start pronouncing the first words of a sentence while still working on further details of its semantic content. An important advantage is memory economy. Semantic and syntactic fragments do not have to occupy working memory until complete semantic and syntactic structures for an utterance have been computed. Instead, each semantic and syntactic fragment is processed as soon as possible and is kept in working memory for a minimum period of time. This raises the question of how the sentence production system can maintain syntactic coherence across syntactic fragments. Presumably there are processes of "syntactic bookkeeping" which (1) store in working memory those syntactic properties of a fragmentary sentence which are needed to eliminate ungrammatical continuations, and (2) check whether a prospective continuation is indeed compatible with the sentence constructed so far. In reaction time experiments where subjects described, under time pressure, simple static pictures of an action performed by an actor, the second aspect of syntactic bookkeeping could be demonstrated. This evidence is used for modelling bookkeeping processes as part of a computational sentence generator which aims at simulating the syntactic operations people carry out during spontaneous speech.

Abstract

This article presents a psycholinguistically inspired approach to the syntax of clause-level coordination and coordinate ellipsis. It departs from the assumption that coordinations are structurally similar to so-called appropriateness repairs — an important type of self-repairs in spontaneous speech. Coordinate structures and appropriateness repairs can both be viewed as “update” constructions. Updating is defined as a special sentence production mode that efficiently revises or augments existing sentential structure in response to modifications in the speaker's communicative intention. This perspective is shown to offer an empirically satisfactory and theoretically parsimonious account of two prominent types of coordinate ellipsis, in particular “forward conjunction reduction” (FCR) and “gapping” (including “long-distance gapping” and “subgapping”). They are analyzed as different manifestations of “incremental updating” — efficient updating of only part of the existing sentential structure. Based on empirical data from Dutch and German, novel treatments are proposed for both types of clausal coordinate ellipsis. The coordination-as-updating perspective appears to explain some general properties of coordinate structure: the existence of the well-known “coordinate structure constraint”, and the attractiveness of three-dimensional representations of coordination. Moreover, two other forms of coordinate ellipsis — SGF (“subject gap in finite clauses with fronted verb”), and “backward conjunction reduction” (BCR) (also known as “right node raising” or RNR) — are shown to be incompatible with the notion of incremental updating. Alternative theoretical interpretations of these phenomena are proposed. The four types of clausal coordinate ellipsis — SGF, gapping, FCR and BCR — are argued to originate in four different stages of sentence production: Intending (i.e., preparing the communicative intention), conceptualization, grammatical encoding, and phonological encoding, respectively.

Abstract

This paper presents a theory of the syntactic aspects of human sentence production. An important characteristic of unprepared speech is that overt pronunciation of a sentence can be initiated before the speaker has completely worked out the meaning content he or she is going to express in that sentence. Apparently, the speaker is able to build up a syntactically coherent utterance out of a series of syntactic fragments each rendering a new part of the meaning content. This incremental, left-to-right mode of sentence production is the central capability of the proposed Incremental Procedural Grammar (IPG). Certain other properties of spontaneous speech, as derivable from speech errors, hesitations, self-repairs, and language pathology, are accounted for as well. The psychological plausibility thus gained by the grammar appears compatible with a satisfactory level of linguistic plausibility in that sentences receive structural descriptions which are in line with current theories of grammar. More importantly, an explanation for the existence of configurational conditions on transformations and other linguistics rules is proposed. The basic design feature of IPG which gives rise to these psychologically and linguistically desirable properties, is the “Procedures + Stack” concept. Sentences are built not by a central constructing agency which overlooks the whole process but by a team of syntactic procedures (modules) which work-in parallel-on small parts of the sentence, have only a limited overview, and whose sole communication channel is a stock. IPG covers object complement constructions, interrogatives, and word order in main and subordinate clauses. It handles unbounded dependencies, cross-serial dependencies and coordination phenomena such as gapping and conjunction reduction. It is also capable of generating self-repairs and elliptical answers to questions. IPG has been implemented as an incremental Dutch sentence generator written in LISP.

Abstract

We outline an algorithm capable of generating varied but natural sounding sequences of argument NPs in subordinate clauses of German, a semi-free word order language. In order to attain the right level of output flexibility, the algorithm considers (1) the relevant lexical properties of the head verb (not only transitivity type but also reflexivity, thematic relations expressed by the NPs, etc.), and (2) the animacy and definiteness values of the arguments, and their length. The relevant statistical data were extracted from the NEGRA–II treebank and from hand-coded features for animacy and definiteness. The algorithm maps the relevant properties onto “primary” versus “secondary” placement options in the generator. The algorithm is restricted in that it does not take into account linear order determinants related to the sentence’s information structure and its discourse context (e.g. contrastiveness). These factors may modulate the above preferences or license “tertiary” linear orders beyond the primary and secondary options considered here.

Abstract

Human speakers often produce sentences incrementally. They can start speaking having in mind only a fragmentary idea of what they want to say, and while saying this they refine the contents underlying subsequent parts of the utterance. This capability imposes a number of constraints on the design of a syntactic processor. This paper explores these constraints and evaluates some recent computational sentence generators from the perspective of incremental production.

Abstract

Remarques sur les facteurs intervenant dans le processus de formulation des énoncés.

Abstract

The psychology of language as developed by Wilhelm Wundt in his fundamental work Die Sprache (1900) has a strongly mentalistic character. The dominating positions held by behaviorism in psychology and structuralism in linguistics have overruled Wundt’s language theory to the effect that it has remained relatively unknown. This situation has changed recently under the influence of transformational linguistics and cognitive psychology. The paper discusses how Wundt applied the basic psychological concepts of apperception and association to language behavior, in particular to the construction and production of sentences during unprepared speech. The final part of the paper is devoted to the work, published in 1917, of the Dutch linguistic scholar Jacques van Ginneken, who elaborated Wundt’s ideas towards an explanation of some syntactic phenomena during the language acquisition of children.

Abstract

Listeners cannot recognize highly reduced word forms in isolation, but they can do so when these forms are presented in context (Ernestus, Baayen, & Schreuder, 2002). This suggests that not all possible surface forms of words have equal status in the mental lexicon. The present study shows that the reduced forms are linked to the canonical representations in the mental lexicon, and that these latter representations induce reconstruction processes. Listeners restore suffixes that are partly or completely missing in reduced word forms. A series of phoneme-monitoring experiments reveals the nature of this restoration: the basis for suffix restoration is mainly phonological in nature, but orthography has an influence as well.

Abstract

This dissertation investigates two seemingly contradictory properties of the speech perception system. On the one hand, listeners are extremely sensitive to the fine phonetic details in the speech signal. These subtle acoustic cues can reduce the temporal ambiguity between words that show initial segmental overlap, and can guide lexical activation. On the other hand, comprehension does not seem to be hampered at all by the drastic reductions that typically occur in casual speech. Complete segments, and sometimes even complete syllables, may be missing, but comprehension is seemingly unaffected. This thesis aims at elucidating how words are represented and accessed in the mental lexicon, by investigating these contradictory phenomena for the domain of morphology

Abstract

The Max Planck Institute for Psycholinguistics in Nijmegen, The Netherlands, is creating a state-of-the-art web environment for the ISO TC 37 (terminology and other language and content resources) metadata registry. This Data Category Registry (DCR) is called ISOcat and encompasses data categories for a broad range of language resources. Under the governance of the DCR Board, ISOcat provides an open work space for creating data category specifications, defining Data Category Selections (DCSs) (domain-specific groups of data categories), and standardising selected data categories and DCSs. Designers visualise future interactivity among the DCR, reference registries and ontological knowledge spaces

Abstract

Spatial terms in the world’s languages appear to reflect both universal conceptual tendencies and linguistic convention. A similarly mixed picture in the case of color naming has been accounted for in terms of near-optimal partitions of color space. Here, we demonstrate that this account generalizes to spatial terms. We show that the spatial terms of 9 diverse languages near-optimally partition a similarity space of spatial meanings, just as color terms near-optimally partition color space. This account accommodates both universal tendencies and cross-language differences in spatial category extension, and identifies general structuring principles that appear to operate across different semantic domains.

Abstract

Drozd's critique of Crain & Thornton's (C&T) (1998) book Investigations in Universal Grammar (IUG) raises many issues concerning theory and experimental design within generative approaches to language acquisition. I focus here on one of the strongest theoretical claims of the Modularity Matching Model (MMM): continuity of processing. For reasons different to Drozd, I argue that the assumption is tenuous. Furthermore, I argue that the focus of the MMM and the methodological prescriptions contained in IUG are too narrow to capture language acquisition.

Abstract

Pauses during continuous speech, particularly those that occur within clauses, are thought to reflect the planning of forthcoming verbal output. We used functional Magnetic Resonance Imaging (fMRI) to examine their neural correlates. Six volunteers were scanned while describing seven Rorschach inkblots, producing 3 min of speech per inkblot. In an event-related design, the level of blood oxygenation level dependent (BOLD) contrast during brief speech pauses (mean duration 1.3 s, SD 0.3 s) during overt speech was contrasted with that during intervening periods of articulation. We then examined activity associated with pauses that occurred within clauses and pauses that occurred between grammatical junctions. Relative to articulation during speech, pauses were associated with activation in the banks of the left superior temporal sulcus (BA 39/22), at the temporoparietal junction. Continuous speech was associated with greater activation bilaterally in the inferior frontal (BA 44/45), middle frontal (BA 8) and anterior cingulate (BA 24) gyri, the middle temporal sulcus (BA 21/22), the occipital cortex and the cerebellum. Left temporal activation was evident during pauses that occurred within clauses but not during pauses at grammatical junctions. In summary, articulation during continuous speech involved frontal, temporal and cerebellar areas, while pausing was associated with activity in the left temporal cortex, especially when this occurred within a clause. The latter finding is consistent with evidence that within-clause pauses are a correlate of speech planning and in particular lexical retrieval.

Abstract

In the first, critical part of this study, a small sample of simple German sentences with their empirically determined pitch contours is used to demonstrate the incorrectness of numerous currently hold views of German sentence intonation. In the second, more constructive part, several interrogative sentence types are analysed and an attempt is made to show that intonation, besides other functions, indicates the permantently changing 'thematic score' in on-going discourse as well as certain validity claims.

Abstract

The Max Planck Institute for Psycholinguistics (MPI) manages an archive of linguistic research data with a current size of almost 20 Terabytes. Apart from in-house researchers other projects also store their data in the archive, most notably the Documentation of Endangered Languages (DoBeS) projects. The archive is available online and can be accessed by anybody with Internet access. To be able to manage this large amount of data the MPI's technical group has developed a software suite called Language Archiving Technology (LAT) that on the one hand helps researchers and archive managers to manage the data and on the other hand helps users in enriching their primary data with additional layers. All the MPI software is Java-based and developed according to open source principles (GNU, 2007). All three major operating systems (Windows, Linux, MacOS) are supported and the software works similarly on all of them. As the archive is online, many of the tools, especially the ones for accessing the data, are browser based. Some of these browser-based tools make use of Adobe Flex to create nice-looking GUIs. The LAT suite is a complete set of management and enrichment tools, and given the interaction between the tools the result is a complete LAT software domain. Over the last 10 years, this domain has proven its functionality and use, and is being deployed to servers in other institutions. This deployment is an important step in getting the archived resources back to the members of the speech communities whose languages are documented. In the paper we give an overview of the tools of the LAT suite and we describe their functionality and role in the integrated process of archiving, management and enrichment of linguistic data.