Publications

Abstract

Two lexical decision studies examined the effects of single-phoneme mismatches on lexical activation in spoken-word recognition. One study was carried out in English, and involved spoken primes and visually presented lexical decision targets. The other study was carried out in Dutch, and primes and targets were both presented auditorily. Facilitation was found only for spoken targets preceded immediately by spoken primes; no facilitation occurred when targets were presented visually, or when intervening input occurred between prime and target. The effects of vowel mismatches and consonant mismatches were equivalent.

Abstract

One of a listener's major tasks in understanding continuous speech is segmenting the speech signal into separate words. When listening conditions are difficult, speakers can help listeners by deliberately speaking more clearly. In four experiments, we examined how word boundaries are produced in deliberately clear speech. In an earlier report we showed that speakers do indeed mark word boundaries in clear speech, by pausing at the boundary and lengthening pre-boundary syllables; moreover, these effects are applied particularly to boundaries preceding weak syllables. In English, listeners use segmentation procedures which make word boundaries before strong syllables easier to perceive; thus marking word boundaries before weak syllables in clear speech will make clear precisely those boundaries which are otherwise hard to perceive. The present report presents supplementary data, namely prosodic analyses of the syllable following a critical word boundary. More lengthening and greater increases in intensity were applied in clear speech to weak syllables than to strong. Mean F0 was also increased to a greater extent on weak syllables than on strong. Pitch movement, however, increased to a greater extent on strong syllables than on weak. The effects were, however, very small in comparison to the durational effects we observed earlier for syllables preceding the boundary and for pauses at the boundary.

Abstract

We show that Atkinson’s (Reports, 15 April 2011, p. 346) intriguing proposal—that global
linguistic diversity supports a single language origin in Africa—is an artifact of using suboptimal
data, biased methodology, and unjustified assumptions. We criticize his approach using more
suitable data, and we additionally provide new results suggesting a more complex scenario for the
emergence of global linguistic diversity.

Abstract

Evidence from certain geographical areas links lymphomas of the ocular adnexa marginal zone B-cell lymphomas (OAMZL) with Chlamydophila psittaci (Cp) infection, suggesting that lymphoma development is dependent upon chronic stimulation by persistent infections. Notwithstanding that, the actual immunopathogenetical mechanisms have not yet been elucidated. As in other B-cell lymphomas, insight into this issue, especially with regard to potential selecting ligands, could be provided by analysis of the immunoglobulin (IG) receptors of the malignant clones. To this end, we studied the molecular features of IGs in 44 patients with OAMZL (40% Cp-positive), identifying features suggestive of a pathogenic mechanism of autoreactivity. Herein, we show that lymphoma cells express a distinctive IG repertoire, with electropositive antigen (Ag)-binding sites, reminiscent of autoantibodies (auto-Abs) recognizing DNA. Additionally, five (11%) cases of OAMZL expressed IGs homologous with autoreactive Abs or IGs of patients with chronic lymphocytic leukemia, a disease known for the expression of autoreactive IGs by neoplastic cells. In contrast, no similarity with known anti-Chlamydophila Abs was found. Taken together, these results strongly indicate that OAMZL may originate from B cells selected for their capability to bind Ags and, in particular, auto-Ags. In OAMZL associated with Cp infection, the pathogen likely acts indirectly on the malignant B cells, promoting the development of an inflammatory milieu, where auto-Ags could be exposed and presented, driving proliferation and expansion of self-reactive B cells.

Abstract

Researchers interested in face processing have recently debated whether access to the name of a known person occurs in parallel with retrieval of semantic-biographical codes, rather than in a sequential fashion. Recently, Schweinberger, Burton, and Kelly (2001) took a failure to obtain a semantic context effect in a manual syllable judgment task on names of famous faces as support for this position. In two experiments, we compared the effects of visually presented categorically related prime words with either objects (e.g. prime: animal; target: dog) or faces of celebrities (e.g. prime: actor; target: Bruce Willis) as targets. Targets were either manually categorized with regard to the number of syllables (as in Schweinberger et al.), or they were overtly named. For neither objects nor faces was semantic priming obtained in syllable decisions; crucially, however, priming was obtained when objects and faces were overtly named. These results suggest that both face and object naming are susceptible to semantic context effects

Abstract

The morphosyntactic paradigm of an inflected word can influence isolated word recognition, but its role in multiple-word phrasal integration is less clear. We examined the electrophysiological response to adjectives in short German prepositional phrases to evaluate whether strong and weak forms of the adjective show a differential response, and whether paradigm variables are related to this response. Twenty native German speakers classified serially presented phrases as grammatically correct or not while the electroencephalogram (EEG) was recorded. A functional mixed effects model of the response to grammatically correct trials revealed a differential response to strong and weak forms of the adjectives. This response difference depended on whether the preceding preposition imposed accusative or dative case. The lexically conditioned information content of the adjectives modulated a later interval of the response. The results indicate that grammatical context modulates the response to morphosyntactic information content, and lends support to the role of paradigm structure in integrative phrasal processing.

Abstract

Language is the best example of a cultural evolutionary system, able to retain a phylogenetic signal over many thousands of years. The temporal stability (conservatism) of basic vocabulary is relatively well understood, but the stability of the structural properties of language (phonology, morphology, syntax) is still unclear. Here we report an extensive Bayesian phylogenetic investigation of the structural stability of numerous features across many language families and we introduce a novel method for analyzing the relationships between the “stability profiles” of language families. We found that there is a strong universal component across language families, suggesting the existence of universal linguistic, cognitive and genetic constraints. Against this background, however, each language family has a distinct stability profile, and these profiles cluster by geographic area and likely deep genealogical relationships. These stability profiles reveal, for example, the ancient historical relationships between the Siberian and American language families, presumed to be separated by at least 12,000 years. Thus, such higher-level properties of language seen as an evolutionary system might allow the investigation of ancient connections between languages and shed light on the peopling of the world.

Abstract

Commentary on Cohen, E. (2012). The evolution of tag-based cooperation in humans: The case for accent. Current Anthropology, 53, 588-616. doi:10.1086/667654.

Abstract

People automatically chunk ongoing dynamic events into discrete units. This paper investigates whether linguistic structure is a factor in this process. We test the claim that describing an event with a serial verb construction will influence a speaker’s conceptual event structure. The grammar of Avatime (a Kwa language spoken in Ghana)requires its speakers to describe some, but not all, placement events using a serial verb construction which also encodes the preceding taking event. We tested Avatime and English speakers’ recognition memory for putting and taking events. Avatime speakers were more likely to falsely recognize putting and taking events from episodes associated with takeput serial verb constructions than from episodes associated with other constructions. English speakers showed no difference in false recognitions between episode types. This demonstrates that memory for episodes is related to the type of language used; and, moreover, across languages different conceptual representations are formed for the same physical episode, paralleling habitual linguistic practices

Abstract

Speakers choose a particular expression based on many factors, including availability of the referent in the perceptual context. We examined whether, when expressing referents, monolingual English- and Turkish-speaking children: (1) are sensitive to perceptual context, (2) express this sensitivity in language-specific ways, and (3) use co-speech gestures to specify referents that are underspecified. We also explored the mechanisms underlying children's sensitivity to perceptual context. Children described short vignettes to an experimenter under two conditions: The characters in the vignettes were present in the perceptual context (perceptual context); the characters were absent (no perceptual context). Children routinely used nouns in the no perceptual context condition, but shifted to pronouns (English-speaking children) or omitted arguments (Turkish-speaking children) in the perceptual context condition. Turkish-speaking children used underspecified referents more frequently than English-speaking children in the perceptual context condition; however, they compensated for the difference by using gesture to specify the forms. Gesture thus gives children learning structurally different languages a way to achieve comparable levels of specification while at the same time adhering to the referential expressions dictated by their language.

Abstract

Abnormal prosody is a striking feature of the speech of those with Autism Spectrum Disorder (ASD), but previous reports suggest large variability among those with ASD. Here we show that part of this heterogeneity can be explained by level of language functioning. We recorded semi-spontaneous but controlled conversations in adults with and without Autism Spectrum Disorder and measured features related to pitch and duration to determine (1) general use of prosodic features, (2) prosodic use in relation to marking information structure, specifically, the emphasis of new information in a sentence (focus) as opposed to information already given in the conversational context (topic), and (3) the relation between prosodic use and level of language function. We found that, compared to typical adults, those with ASD with high language functioning generally used a larger pitch range than controls but did not mark information structure, whereas those with moderate language functioning generally used a smaller pitch range than controls but marked information structure appropriately to a large extent. Both impaired general prosodic use and impaired marking of information structure would be expected to seriously impact social communication and thereby lead to increased difficulty in personal domains, such as making and keeping friendships, and in professional domains, such as competing for employment opportunities.

Abstract

Developmental dyslexia, a severe and persistent reading and spelling impairment, is characterized by difficulties in processing speech sounds (i.e., phonemes). Here, we test the hypothesis that these phonological difficulties are associated with a dysfunction of the auditory sensory thalamus, the medial geniculate body (MGB). By using functional MRI, we found that, in dyslexic adults, the MGB responded abnormally when the task required attending to phonemes compared with other speech features. No other structure in the auditory pathway showed distinct functional neural patterns between the two tasks for dyslexic and control participants. Furthermore, MGB activity correlated with dyslexia diagnostic scores, indicating that the task modulation of the MGB is critical for performance in dyslexics. These results suggest that deficits in dyslexia are associated with a failure of the neural mechanism that dynamically tunes MGB according to predictions from cortical areas to optimize speech processing. This view on task-related MGB dysfunction in dyslexics has the potential to reconcile influential theories of dyslexia within a predictive coding framework of brain function.

Abstract

The extent to which the phonetic system of a second language is mastered varies across individuals. The present study evaluates the pattern of individual differences in late bilinguals across different phonological processes. Fifty-five late Dutch-English bilinguals were tested on their ability to perceive a difficult L2 speech contrast (the English /æ/-/ε/ contrast) in three different tasks: A categorization task, a word identification task and a lexical decision task. As a group, L2 listeners were less accurate than native listeners. However, at the individual level, almost half of the L2 listeners scored within the native range in the categorization task whereas a small percentage scored within the native range in the identification and lexical decision tasks. These results show that L2 listeners' performance crucially depends on the nature of the task, with higher L2 listener accuracy on an acoustic-phonetic analysis task than on tasks involving lexical processes. These findings parallel previous results for early bilinguals, where the pattern of performance was consistent with the processing hierarchy proposed by different models of speech perception. The results indicate that the analysis of patterns of non-native performance can provide important insights concerning the architecture of the speech perception system and the issue of language learnability.

Abstract

Prosody, particularly accent, aids comprehension by drawing attention to important elements such as the information that answers a question. A study using ERP registration investigated how the brain deals with the interpretation of prosodic prominence. Sentences were embedded in short dialogues and contained accented elements that were congruous or incongruous with respect to a preceding question. In contrast to previous studies, no explicit prosodic judgment task was added. Robust effects of accentuation were evident in the form of an “accent positivity” (200–500 msec) for accented elements irrespective of their congruity. Our results show that incongruously accented elements, that is, superfluous accents, activate a specific set of neural systems that is inactive in case of incongruously unaccented elements, that is, missing accents. Superfluous accents triggered an early positivity around 100 msec poststimulus, followed by a right-lateralized negative effect (N400). This response suggests that redundant information is identified immediately and leads to the activation of a neural system that is associated with semantic processing (N400). No such effects were found when contextually expected accents were missing. In a later time window, both missing and superfluous accents triggered a late positivity on midline electrodes, presumably related to making sense of both kinds of mismatching stimuli. These results challenge previous findings of greater processing for missing accents and suggest that the natural processing of prosody involves a set of distinct, temporally organized neural systems.

Abstract

The present dissertation investigates what neurocognitive processes are activated in the brain when listeners comprehend spoken language and in particular the melody and rhythm of speech, also referred to as prosody. The findings of several electrophysiological studies show that prosody influences the early and late stages of spoken language processing. When words are accented, listeners consider them important, and the brain responds to accentuation already 200 milliseconds after stimulus onset. The processing of prosodic prominence occurs whether or not a context is present and whether or not accent is congruent with context, although the responses to accentuation may be modified by either of these factors and by the focus particle only. Listeners are sensitive not only to the presence of prosodic prominence but also to the type of accents speakers use: corrective prosody activates additional interpretation mechanisms related to the construction of corrective meaning. The parallel between accents across clauses impacts the disambiguation of sentences with verb ellipsis. By interpreting prosodically parallel elements as syntactically parallel, listeners arrive at less preferred interpretations of conjoined clauses. The research indentifies early correlates of incongruous prosody in strongly predictive contexts as well as late integration processes for prosody comprehension, which are related to the processing of structural complexity in isolated and ambiguous sentences. The dissertation provides evidence that the brain is sensitive to differences in prosody even in the absence of prosodic judgment. However, by changing the task, one modulates the neural mechanisms of prosody processing.

Abstract

The papers in this volume focus on the impact of information structure on language acquisition, thereby taking different linguistic approaches into account. They start from an empirical point of view, and examine data from natural first and second language acquisition, which cover a wide range of varieties, from early learner language to native speaker production and from gesture to Creole prototypes. The central theme is the interplay between principles of information structure and linguistic structure and its impact on the functioning and development of the learner's system. The papers examine language-internal explanatory factors and in particular the communicative and structural forces that push and shape the acquisition process, and its outcome. On the theoretical level, the approach adopted appeals both to formal and communicative constraints on a learner’s language in use. Two empirical domains provide a 'testing ground' for the respective weight of grammatical versus functional determinants in the acquisition process: (1) the expression of finiteness and scope relations at the utterance level and (2) the expression of anaphoric relations at the discourse level.

Abstract

We present a new transcription mode for the annotation tool ELAN. This mode is designed to speed up the process of creating transcriptions of primary linguistic data (video and/or audio recordings of linguistic behaviour). We survey the basic transcription workflow of some commonly used tools (Transcriber, BlitzScribe, and ELAN) and describe how the new transcription interface improves on these existing implementations. We describe the design of the transcription interface and explore some further possibilities for improvement in the areas of segmentation and computational enrichment of annotations.

Abstract

Ideophones are marked words that depict sensory imagery found in many of the world’s languages. They are noted for their special forms, distinct grammatical behaviour, rich sensory meanings, and interactional uses related to experience and evidentiality. This review surveys recent developments in ideophone research. Work on the semiotics of ideophones helps explain why they are marked and how they realise the depictive potential of speech. A true semantic typology of ideophone systems is coming within reach through a combination of language-internal analyses and language-independent elicitation tools. Documentation of ideophones in a wide variety of genres as well as sequential analysis of ideophone use in natural discourse leads to new insights about their interactional uses and about their relation to other linguistic devices like reported speech and grammatical evidentials. As the study of ideophones is coming of age, it sheds new light on what is possible and probable in human language.

Abstract

Mensen groeien op in verschillende omgevingen, met verschillende ervaringen en verschillende talen. Betekent dat ook dat ze verschillend denken? En als er invloed is van taal op denken, hoe ver reikt die dan? Wordt ons denken begrensd door woorden, of is de invloed meer gematigd en kunnen we er soms zelfs aan ontkomen?

Abstract

The widespread occurrence of ideophones, large classes of words specialized in evoking sensory imagery, is little known outside linguistics and anthropology. Ideophones are a common feature in many of the world’s languages but are underdeveloped in English and other Indo-European languages. Here we study the meanings of ideophones in Siwu (a Kwa language from Ghana) using a pile-sorting task. The goal was to uncover the underlying structure of the lexical space and to examine the claimed link between ideophones and perception. We found that Siwu ideophones are principally organized around fine-grained aspects of sensory perception, and map onto salient psychophysical dimensions identified in sensory science. The results ratify ideophones as dedicated sensory vocabulary and underline the relevance of ideophones for research on language and perception.

Abstract

People often talk about musical pitch in terms of spatial metaphors. In English, for instance, pitches can be high or low, whereas in other languages pitches are described as thick or thin. According to psychophysical studies, metaphors in language can also shape people’s nonlinguistic space-pitch representations. But does language establish mappings between space and pitch in the first place or does it modify preexisting associations? Here we tested 4-month-old Dutch infants’ sensitivity to height-pitch and thickness-pitch mappings in two preferential looking tasks. Dutch infants looked significantly longer at cross-modally congruent stimuli in both experiments, indicating that infants are sensitive to space-pitch associations prior to language. This early presence of space-pitch mappings suggests that these associations do not originate from language. Rather, language may build upon pre-existing mappings and change them gradually via some form of competitive associative learning.

Abstract

This paper presents Advanced Glossing, a proposal for a general glossing format designed for language documentation, and a specific setup for the Shoebox-program that implements Advanced Glossing to a large extent. Advanced Glossing (AG) goes beyond the traditional Interlinear Morphemic Translation, keeping syntactic and morphological information apart from each other in separate glossing tables. AG provides specific lines for different kinds of annotation – phonetic, phonological, orthographical, prosodic, categorial, structural, relational, and semantic, and it allows for gradual and successive, incomplete, and partial filling in case that some information may be irrelevant, unknown or uncertain. The implementation of AG in Shoebox sets up several databases. Each documented text is represented as a file of syntactic glossings. The morphological glossings are kept in a separate database. As an additional feature interaction with lexical databases is possible. The implementation makes use of the interlinearizing automatism provided by Shoebox, thus obtaining the table format for the alignment of lines in cells, and for semi-automatic filling-in of information in glossing tables which has been extracted from databases

Abstract

Digitizing and annotating texts and field recordings Given that several initiatives worldwide currently explore the new field of documentation of endangered languages, the E-MELD project proposes to survey and unite procedures, techniques and results in order to achieve its main goal, ''the formulation and promulgation of best practice in linguistic markup of texts and lexicons''. In this context, this year's workshop deals with the processing of recorded texts. I assume the most valuable contribution I could make to the workshop is to show the procedures and methods used in the Awetí Language Documentation Project. The procedures applied in the Awetí Project are not necessarily representative of all the projects in the DOBES program, and they may very well fall short in several respects of being best practice, but I hope they might provide a good and concrete starting point for comparison, criticism and further discussion. The procedures to be exposed include: * taping with digital devices, * digitizing (preliminarily in the field, later definitely by the TIDEL-team at the Max Planck Institute in Nijmegen), * segmenting and transcribing, using the transcriber computer program, * translating (on paper, or while transcribing), * adding more specific annotation, using the Shoebox program, * converting the annotation to the ELAN-format developed by the TIDEL-team, and doing annotation with ELAN. Focus will be on the different types of annotation. Especially, I will present, justify and discuss Advanced Glossing, a text annotation format developed by H.-H. Lieb and myself designed for language documentation. It will be shown how Advanced Glossing can be applied using the Shoebox program. The Shoebox setup used in the Awetí Project will be shown in greater detail, including lexical databases and semi-automatic interaction between different database types (jumping, interlinearization). ( Freie Universität Berlin and Museu Paraense Emílio Goeldi, with funding from the Volkswagen Foundation.)

Abstract

Overview Since the early nineties, the on-going dramatic loss of the world’s linguistic diversity has gained attention, first by the linguists and increasingly also by the general public. As a response, the new field of language documentation emerged from around 2000 on, starting with the funding initiative ‘Dokumentation Bedrohter Sprachen’ (DoBeS, funded by the Volkswagen foundation, Germany), soon to be followed by others such as the ‘Endangered Languages Documentation Programme’ (ELDP, at SOAS, London), or, in the USA, ‘Electronic Meta-structure for Endangered Languages Documentation’ (EMELD, led by the LinguistList) and ‘Documenting Endangered Languages’ (DEL, by the NSF). From its very beginning, the new field focused on digital technologies not only for recording in audio and video, but also for annotation, lexical databases, corpus building and archiving, among others. This development not just coincides but is intrinsically interconnected with the increasing focus on digital data, technology and methods in all sciences, in particular in the humanities.

Abstract

This contribution explores the potentials of combining corpora of language use data with language description in e-grammars (or digital grammars). We present three directions of ongoing research and discuss the advantages of combining these and similar approaches, arguing that the technological possibilities have barely begun to be explored.

Abstract

This contribution presents “The Language Archive” (TLA), a new unit at the MPI for Psycholinguistics, discussing the current developments in management of scientific data, considering the need for new data research infrastructures. Although several initiatives worldwide in the realm of language resources aim at the integration, preservation and mobilization of research data, the state of such scientific data is still often problematic. Data are often not well organized and archived and not described by metadata ― even unique data such as field-work observational data on endangered languages is still mostly on perishable carriers. New data centres are needed that provide trusted, quality-reviewed, persistent services and suitable tools and that take legal and ethical issues seriously. The CLARIN initiative has established criteria for suitable centres. TLA is in a good position to be one of such centres. It is based on three essential pillars: (1) A data archive; (2) management, access and annotation tools; (3) archiving and software expertise for collaborative projects. The archive hosts mostly observational data on small languages worldwide and language acquisition data, but also data resulting from experiments

Abstract

Traditionally, there have been three standard assumptions made about the Parallelism Effect on VP-ellipsis, namely that the effect is categorical, that it applies asymmetrically and that it is uniquely due to syntactic factors. Based on the results of a series of experiments involving online and offline tasks, it will be argued that the Parallelism Effect is instead noncategorical and interactional. The factors investigated include construction type, conceptual and morpho-syntactic recoverability, finiteness and anaphor type (to test VP-anaphora). The results show that parallelism is gradient rather than categorical, effects both VP-ellipsis and anaphora, and is influenced by both structural and non-structural factors.

Abstract

Although laughter forms an important part of human non-verbal communication, it has received rather less attention than it deserves in both the experimental and the observational literatures. Relaxed social (Duchenne) laughter is associated with feelings of wellbeing and heightened affect, a proximate expla- nation for which might be the release of endorphins. We tested this hypothesis in a series of six experimental studies in both the laboratory (watching videos) and naturalistic contexts (watching stage performances), using change in pain threshold as an assay for endorphin release. The results show that pain thresholds are significantly higher after laughter than in the control condition. This pain-tolerance effect is due to laughter itself and not simply due to a change in positive affect. We suggest that laughter, through an endorphin-mediated opiate effect, may play a crucial role in social bonding.

Abstract

In the absence of comparative method reconstruction, high rate of lexical cognate candidates is often used as evidence for relationships between languages. This paper uses the Oswalt Monte Carlo Shift test (a variant of Oswalt 1970) to explore the statistical basis of the claim that the four Papuan languages of the Solomon Islands have greater than chance levels of lexical similarity. The results of this test initially appear to show that the lexical similarities between the Central Solomons Papuan languages are statistically significant, but the effect disappears when known Oceanic loanwords are removed. The Oswalt Monte Carlo test is a useful technique to test a claim of greater than chance similarity between any two word lists — with the proviso that undetected loanwords strongly increase the chance of spurious identification.

Abstract

A review of "Anthropological papers of the University of Alaska: The Dene-Yeniseian connection." Ed. by JAMES KARI and BEN A. POTTER Fairbanks, AK: University of Alaska, Fairbanks. 2010. Pp. vi, 363.

Abstract

The Island Melanesia project was initiated to collect data on the little-known Papuan languages of Island Melanesia, and to explore the origins of and relationships between these languages. The project materials from the 2003 field season focus on language related to cultural domains (e.g., material culture) and on targeted grammatical description. Five tasks are included: Proto-Oceanic lexicon, Grammatical questionnaire and lexicon, Kinship questionnaire, Domains of likely pre-Austronesian terminology, and Botanical collection questionnaire.

Abstract

Approach and avoidance are two behavioral responses that make people tend to approach positive and avoid negative situations. This study examines whether postural behavior is influenced by the affective state of pictures. While standing on the Wii™ Balance Board, participants viewed pleasant, neutral, and unpleasant pictures (passively viewing phase). Then they had to move their body to the left or the right (lateral movement phase) to make the next picture appear. We recorded movements in the anterior-posterior direction to examine approach and avoidant behavior. During passively viewing, people approached pleasant pictures. They avoided unpleasant ones while they made a lateral movement. These findings provide support for the idea that we tend to approach positive and avoid negative situations.

Abstract

How involved in an event is a person that possesses one of the event participants? Some languages can treat such “external possessors” as very closely involved, even marking them on the verb along with core roles such as subject and object. Other languages only allow possessors to be expressed as non-core participants. This task explores possibilities for the encoding of possessors and other related roles such as beneficiaries. The materials consist of a sequence of thirty drawings designed to elicit target construction types.

Abstract

1. Introduction Speech conveys not only linguistic meaning but also paralinguistic information, such as features of the speaker’s social background, physiology, and emotional state. Linguistic and paralinguistic information is encoded in speech by using largely the same vocal apparatus and both are transmitted simultaneously in the acoustic signal, drawing on a limited set of acoustic cues. How this simultaneous encoding is achieved, how the different types of information are disentangled by the listener, and how much they interfere with one another is presently not well understood. Previous research has highlighted the importance of acoustic source and filter cues for emotion and linguistic encoding respectively, which may suggest that the two types of information are encoded independently of each other. However, those lines of investigation have been almost completely disconnected (Murray & Arnott, 1993).

Abstract

Definition Perceptual learning in speech describes a change in the mapping from acoustic cues in the speech signal to abstract linguistic representations. Learning leads to a lasting benefit to the listener by improving speech comprehension. The change can occur as a response to a specific feature (such as a talker- or accent idiosyncrasy) or to a global degradation of the signal (such as in synthesized or compressed speech). In perceptual learning, a top-down process is involved in causing the change, whereas purely bottom-up, signal-driven phenomena are considered to be adaptation.

Abstract

Language resource centers allow researchers to reliably deposit their structured data together with associated meta data and run services operating on this deposited data. We are looking into possibilities to create long-term persistency of both the deposited data and the services operating on this data. Challenges, both technical and non-technical, that need to be solved are the need to replicate more than just the data, proper identification of the digital objects in a distributed environment by making use of persistent identifiers and the set-up of a proper authentication and authorization domain including the management of the authorization information on the digital objects. We acknowledge the investment that most language resource centers have made in their current infrastructure. Therefore one of the most important requirements is the loose coupling with existing infrastructures without the need to make many changes. This shift from a single language resource center into a federated environment of many language resource centers is discussed in the context of a real world center: The Language Archive supported by the Max Planck Institute for Psycholinguistics.

Abstract

In the present article, we introduce the continuous unified electronic (CUE) diary method, a longitudinal, event-based, electronic parent report method that allows real-time recording of infant and child behavior in natural contexts. Thirty-nine expectant mothers were trained to identify and record target behaviors into programmed handheld computers. From birth to 18 months, maternal reporters recorded the initial, second, and third occurrences of seven target motor behaviors: palmar grasp, rolls from side to back, reaching when sitting, pincer grip, crawling, walking, and climbing stairs. Compliance was assessed as two valid entries per behavior: 97 % of maternal reporters met compliance criteria. Reliability was assessed by comparing diary entries with researcher assessments for three of the motor behaviors: palmar grasp, pincer grip and walking. A total of 81 % of maternal reporters met reliability criteria. For those three target behaviors, age of emergence was compared across data from the CUE diary method and researcher assessments. The CUE diary method was found to detect behaviors earlier and with greater sensitivity to individual differences. The CUE diary method is shown to be a reliable methodological tool for studying processes of change in human development.

Abstract

This article presents a description of two sequences of talk by urban speakers of Lao (a southwestern Tai language spoken in Laos) in which co-speech gesture plays a central role in explanations of kinship relations and terminology. The speakers spontaneously use hand gestures and gaze to spatially diagram relationships that have no inherent spatial structure. The descriptive sections of the article are prefaced by a discussion of the semiotic complexity of illustrative gestures and gesture diagrams. Gestured signals feature iconic, indexical, and symbolic components, usually in combination, as well as using motion and three-dimensional space to convey meaning. Such diagrams show temporal persistence and structural integrity despite having been projected in midair by evanescent signals (i.e., handmovements anddirected gaze). Speakers sometimes need or want to revise these spatial representations without destroying their structural integrity. The need to "edit" gesture diagrams involves such techniques as hold-and-drag, hold-and-work-with-free-hand, reassignment-of-old-chunk-tonew-chunk, and move-body-into-new-space.

Abstract

Words such as what -d'you-call-it raise issues at the heart of the semantics/pragmatics interface. Expressions of this kind are conventionalised and have meanings which, while very general, are explicitly oriented to the interactional nature of the speech context, drawing attention to a speaker's assumption that the listener can figure out what the speaker is referring to. The details of such meanings can account for functional contrast among similar expressions, in a single language as well as cross-linguistically. The English expressions what -d'you-call-it and you-know-what are compared, along with a comparable Lao expression meaning, roughly, ‘that thing’. Proposed definitions of the meanings of these expressions account for their different patterns of use. These definitions include reference to the speech act participants, a point which supports the view that what -d'you-call-it words can be considered deictic. Issues arising from the descriptive section of this paper include the question of how such terms are derived, as well as their degree of conventionality.

Abstract

This task is designed to elicit virtual 3D ‘models’ created in gesture space using iconic and other representational gestures. This task has been piloted with Lao speakers, where two speakers were asked to explain the meaning of terms referring to different kinds of fish trap mechanisms. The task elicited complex performances involving a range of iconic gestures, and with especially interesting use of (a) the ‘model/diagram’ in gesture space as a virtual object, (b) the non-dominant hand as a prosodic/semiotic anchor, (c) a range of different techniques (indexical and iconic) for evoking meaning with the hand, and (d) the use of nearby objects and parts of the body as semiotic ‘props’.

Abstract

The semantics of simple (i.e. two-term) systems of demonstratives have in general hitherto been treated as inherently spatial and as marking a symmetrical opposition of distance (‘proximal’ versus ‘distal’), assuming the speaker as a point of origin. More complex systems are known to add further distinctions, such as visibility or elevation, but are assumed to build on basic distinctions of distance. Despite their inherently context-dependent nature, little previous work has based the analysis of demonstratives on evidence of their use in real interactional situations. In this article, video recordings of spontaneous interaction among speakers of Lao (Southwestern Tai, Laos) are examined in an analysis of the two Lao demonstrative determiners nii4 and nan4. A hypothesis of minimal encoded semantics is tested against rich contextual information, and the hypothesis is shown to be consistent with the data. Encoded conventional meanings must be kept distinct from contingent contextual information and context-dependent pragmatic implicatures. Based on examples of the two Lao demonstrative determiners in exophoric uses, the following claims are made. The term nii4 is a semantically general demonstrative, lacking specification of ANY spatial property (such as location or distance). The term nan4 specifies that the referent is ‘not here’ (encoding ‘location’ but NOT ‘distance’). Anchoring the semantic specification in a deictic primitive ‘here’ allows a strictly discrete intensional distinction to be mapped onto an extensional range of endless elasticity. A common ‘proximal’ spatial interpretation for the semantically more general term nii4 arises from the paradigmatic opposition of the two demonstrative determiners. This kind of analysis suggests a reappraisal of our general understanding of the semantics of demonstrative systems universally. To investigate the question in sufficient detail, however, rich contextual data (preferably collected on video) is necessary

Abstract

Research on video- and audio-recordings of spontaneous naturally-occurring conversation in English has shown that conversation is a rule-guided, practice-oriented domain that can be investigated for its underlying mechanics or structure. Systematic study could yield something like a grammar for conversation. The goal of this task is to acquire a corpus of video-data, for investigating the underlying structure(s) of interaction cross-linguistically and cross-culturally

Abstract

We want to know how people think about their field of kin, on the supposition that it is quasi-spatial. To get some insights here, we need to video a discussion about kinship reckoning, the kinship system, marriage rules and so on, with a view to looking at both the linguistic expressions involved, and the gestures people use to indicate kinship groups and relations. Unlike the task in the 2001 manual, this task is a direct interview method.

Abstract

This task is a complement to the questionnaire ‘Multimodal interaction in your field site: a preliminary investigation’. The objective of the task is to obtain high quality video data on structured and symmetrical dyadic multimodal interaction. The features of interaction we are interested in include turn organization in speech and nonverbal behavior, eye-gaze behavior, use of composite signals (i.e. communicative units of speech-combined-with-gesture), and linguistic and other resources for ‘navigating’ interaction (e.g. words like okay, now, well, and um).

Abstract

Book review of James R. Hurford THE ORIGINS OF GRAMMAR 791pp. Oxford University Press. ISBN 978 0 19 920787 9

Abstract

Noise-vocoded speech is a spectrally highly degraded signal, but it preserves the temporal envelope of speech. Listeners vary considerably in their ability to adapt to this degraded speech signal. Here, we hypothesized that individual differences in adaptation to vocoded speech should be predictable by non-speech auditory, cognitive, and neuroanatomical factors. We tested eighteen normal-hearing participants in a short-term vocoded speech-learning paradigm (listening to 100 4-band-vocoded sentences). Non-speech auditory skills were assessed using amplitude modulation (AM) rate discrimination, where modulation rates were centered on the speech-relevant rate of 4 Hz. Working memory capacities were evaluated (digit span and nonword repetition), and structural MRI scans were examined for anatomical predictors of vocoded speech learning using voxel-based morphometry. Listeners who learned faster to understand degraded speech also showed smaller thresholds in the AM discrimination task. This ability to adjust to degraded speech is furthermore reflected anatomically in increased volume in an area of the left thalamus (pulvinar) that is strongly connected to the auditory and prefrontal cortices. Thus, individual non-speech auditory skills and left thalamus grey matter volume can predict how quickly a listener adapts to degraded speech.

Abstract

Among the most fascinating data for phonology are those showing how speakers incorporate new words and foreign words into their language system, since these data provide cues to the actual principles underlying language. In this article, we address how speakers deal with neutralized obstruents in new words. We formulate four hypotheses and test them on the basis of Dutch word-final obstruents, which are neutral for [voice]. Our experiments show that speakers predict the characteristics ofneutralized segments on the basis ofphonologically similar morphemes stored in the mental lexicon. This effect of the similar morphemes can be modeled in several ways. We compare five models, among them STOCHASTIC OPTIMALITY THEORY and ANALOGICAL MODELING OF LANGUAGE; all perform approximately equally well, but they differ in their complexity, with analogical modeling oflanguage providing the most economical explanation.

Abstract

We investigated whether regional differences in the native language (L1) influence the perception of second language (L2) sounds. Many cross-language and L2 perception studies have assumed that the degree of acoustic similarity between L1 and L2 sounds predicts cross-linguistic and L2 performance. The present study tests this assumption by examining the perception of the English contrast between /e{open}/ and /æ/ in native speakers of Dutch spoken in North Holland (the Netherlands) and in East- and West-Flanders (Belgium). A Linear Discriminant Analysis on acoustic data from both dialects showed that their differences in vowel production, as reported in and Adank, van Hout, and Van de Velde (2007), should influence the perception of the L2 vowels if listeners focus on the vowels' acoustic/auditory properties. Indeed, the results of categorization tasks with Dutch or English vowels as response options showed that the two listener groups differed as predicted by the discriminant analysis. Moreover, the results of the English categorization task revealed that both groups of Dutch listeners displayed the asymmetric pattern found in previous word recognition studies, i.e. English /æ/ was more frequently confused with English /e{open}/ than the reverse. This suggests a strong link between previous L2 word learning results and the present L2 perceptual assimilation patterns.

Abstract

Nuclear orphan receptor TLX (NR2E1) functions primarily as a transcriptional repressor and its pivotal role in brain development, glioblastoma, mental retardation and retinopathologies make it an attractive drug target. TLX is expressed in the neural stem cells (NSCs) of the subventricular zone and the hippocampus subgranular zone, regions with persistent neurogenesis in the adult brain, and functions as an essential regulator of NSCs maintenance and self-renewal. Little is known about the TLX social network of interactors and only few TLX coregulators are described. To identify and characterize novel TLX-binders and possible coregulators, we performed yeast-two-hybrid (Y2H) screens of a human adult brain cDNA library using different TLX constructs as baits. Our screens identified multiple clones of Atrophin-1 (ATN1), a previously described TLX interactor. In addition, we identified an interaction with the oncoprotein and zinc finger transcription factor BCL11A (CTIP1/Evi9), a key player in the hematopoietic system and in major blood-related malignancies. This interaction was validated by expression and coimmunoprecipitation in human cells. BCL11A potentiated the transrepressive function of TLX in an in vitro reporter gene assay. Our work suggests that BCL11A is a novel TLX coregulator that might be involved in TLX-dependent gene regulation in the brain.

Abstract

In the current eye-tracking study, we explored whether 12-month-old infants can predict others' social preferences. We showed infants scenes in which two characters alternately helped or hindered an agent in his goal of climbing a hill. In a control condition, the two characters moved up and down the hill in identical ways to the helper and hinderer but did not make contact with the agent; thus, they did not cause him to reach or not reach her or his goal. Following six alternating familiarization trials of helping and hindering interactions (help-hinder condition) or up and down interactions (up-down condition), infants were shown one test trial in which they could visually anticipate the agent approaching one of the two characters. As predicted, infants in the help-hinder condition made significantly more visual anticipations toward the helping than hindering character, suggesting that they predicted the agent to approach the helping character. In contrast, infants revealed no difference in visual anticipations between the up and down characters. The up-down condition served to control for low-level perceptual explanations of the results for the help-hinder condition. Thus, together the results reveal that 12-month-old infants make predictions about others' behaviour and social preferences from a third-party perspective.

Abstract

Across two experiments, we examined the relationship between 18-month-old infants’ mimicry and social behavior – particularly invitations to play with an adult play partner. In Experiment 1, we manipulated whether an adult mimicked the infant's play or not during an initial play phase. We found that infants who had been mimicked were subsequently more likely to invite the adult to join their play with a new toy. In addition, they reenacted marginally more steps from a social learning demonstration she gave. In Experiment 2, infants had the chance to spontaneously mimic the adult during the play phase. Complementing Experiment 1, those infants who spent more time mimicking the adult were more likely to invite her to play with a new toy. This effect was specific to play and not apparent in other communicative acts, such as directing the adult's attention to an event or requesting toys. Together, the results suggest that infants use mimicry as a tool to establish social connections with others and that mimicry has specific influences on social behaviors related to initiating subsequent joint interactions.

Abstract

Infants imitate others’ individual actions, but do they also replicate others’ joint activities? To examine whether observing joint action influences infants’ initiation of joint action, forty-eight 18-month-old infants observed object demonstrations by 2 models acting together (joint action), 2 models acting individually (individual action), or 1 model acting alone (solitary action). Infants’ behavior was examined after they were given each object. Infants in the joint action condition attempted to initiate joint action more often than infants in the other conditions, yet they were equally likely to communicate for other reasons and to imitate the demonstrated object-directed actions. The findings suggest that infants learn to replicate others’ joint activity through observation, an important skill for cultural transmission of shared practices.

Abstract

We examine representations of time among the Mianmin of Papua New Guinea. We begin by describing the patterns of spatial and temporal reference in Mian. Mian uses a system of spatial terms that derive from the orientation and direction of the Hak and Sek rivers and the surrounding landscape. We then report results from a temporal arrangement task administered to a group of Mian speakers. The results reveal evidence for a variety of temporal representations. Some participants arranged time with respect to their bodies (left to right or toward the body). Others arranged time as laid out on the landscape, roughly along the east/west axis (either east to west or west to east). This absolute pattern is consistent both with the axis of the motion of the sun and the orientation of the two rivers, which provides the basis for spatial reference in the Mian language. The results also suggest an increase in left-to-right temporal representations with increasing years of formal education (and the reverse pattern for absolute spatial representations for time). These results extend previous work on spatial representations for time to a new geographical region, physical environment, and linguistic and cultural system.

Abstract

This study investigates the way adult second language (L2) learners of English resolve relative clause attachment ambiguities in sentences such as The dean liked the secretary of the professor who was reading a letter. Two groups of advanced L2 learners of English with Greek or German as their first language participated in a set of off-line and on-line tasks. The results indicate that the L2 learners do not process ambiguous sentences of this type in the same way as adult native speakers of English do. Although the learners’ disambiguation preferences were influenced by lexical–semantic properties of the preposition linking the two potential antecedent noun phrases (of vs. with), there was no evidence that they applied any phrase structure–based ambiguity resolution strategies of the kind that have been claimed to influence sentence processing in monolingual adults. The L2 learners’ performance also differs markedly from the results obtained from 6- to 7-year-old monolingual English children in a parallel auditory study, in that the children’s attachment preferences were not affected by the type of preposition at all. We argue that children, monolingual adults, and adult L2 learners differ in the extent to which they are guided by phrase structure and lexical–semantic information during sentence processing.

Abstract

The constituents of attractiveness differ across the sexes. Many relevant traits are dimorphic, suggesting that they are the product of intersexual selection. However, direction of causality is generally difficult to determine, as aesthetic criteria can as readily result from, as cause, dimorphism. Women have proportionately smaller feet than men. Prior work on the role of foot size in attractiveness suggests an asymmetry across the sexes, as small feet enhance female appearance, yet average, rather than large, feet are preferred on men. Previous investigations employed crude stimuli and limited samples. Here, we report on multiple cross-cultural studies designed to overcome these limitations. With the exception of one rural society, we find that small foot size is preferred when judging women, yet no equivalent preference applies to men. Similarly, consonant with the thesis that a preference for youth underlies intersexual selection acting on women, we document an inverse relationship between foot size and perceived age. Examination of preferences regarding, and inferences from, feet viewed in isolation suggests different roles for proportionality and absolute size in judgments of female and male bodies. Although the majority of these results bolster the conclusion that pedal dimorphism is the product of intersexual selection, the picture is complicated by the reversal of the usual preference for small female feet found in one rural society. While possibly explicable in terms of greater emphasis on female economic productivity relative to beauty, the latter finding underscores the importance of employing diverse samples when exploring postulated evolved aesthetic preferences.

Abstract

The evolutionary origins of music are much debated. One theory holds that the ability to produce complex musical sounds might reflect qualities that are relevant in mate choice contexts and hence, that music is functionally analogous to the sexually-selected acoustic displays of some animals. If so, women may be expected to show heightened preferences for more complex music when they are most fertile. Here, we used computer-generated musical pieces and ovulation predictor kits to test this hypothesis. Our results indicate that women prefer more complex music in general; however, we found no evidence that their preference for more complex music increased around ovulation. Consequently, our findings are not consistent with the hypothesis that a heightened preference/bias in women for more complex music around ovulation could have played a role in the evolution of music. We go on to suggest future studies that could further investigate whether sexual selection played a role in the evolution of this universal aspect of human culture.

Abstract

What is the key cognitive ability that makes humans unique among all the other animals? Our work aims at contributing to this research question adopting a comparative and philosophical approach to the origins of verbal language. In particular, we adopt three strands of analysis that are relevant in the context of comparative investigation on the the origins of verbal language: a) research on the evolutionary ‘homologies’, which provides information on the phylogenetic traits that humans and other primates share with their common ancestor; b) investigations on “analogous” traits, aimed at finding the evolutionary pressures that guided the emergence of the same biological traits that evolved independently in phylogenetically distant species; the ontogenetic development of the ability to produce and understand verbal language in human infants. Within this comparative approach, we focus on three key apsects that we addressed bridging recent empiric evidence on language processing with philosophical investigations on verbal language: (i) pattern processing as a biologocal precursor of syntax and algebraic rule acquisition, (ii) sound modulation as a guide to pattern comprehension in speech, animal vocalization and music, (iii) social strategies for mutual understanding, survival and group cohesion. We conclude emphasizing the interplay between these three sets of cognitive processes as a fundamental dimension grounding the emergence of the human ability for propositional language.

Abstract

Family and twin studies of developmental dyslexia have consistently shown that there is a significant heritable component for this disorder. However, any genetic basis for the trait is likely to be complex, involving reduced penetrance, phenocopy, heterogeneity and oligogenic inheritance. This complexity results in reduced power for traditional parametric linkage analysis, where specification of the correct genetic model is important. One strategy is to focus on large multigenerational pedigrees with severe phenotypes and/or apparent simple Mendelian inheritance, as has been successfully demonstrated for speech and language impairment. This approach is limited by the scarcity of such families. An alternative which has recently become feasible due to the development of high-throughput genotyping techniques is the analysis of large numbers of sib-pairs using allele-sharing methodology. This paper outlines our strategy for conducting a systematic genome-wide search for genes involved in dyslexia in a large number of affected sib-pair familites from the UK. We use a series of psychometric tests to obtain different quantitative measures of reading deficit, which should correlate with different components of the dyslexia phenotype, such as phonological awareness and orthographic coding ability. This enable us to use QTL (quantitative trait locus) mapping as a powerful tool for localising genes which may contribute to reading and spelling disability.

Abstract

Recent application of nonparametric-linkage analysis to reading disability has implicated a putative quantitative-trait locus (QTL) on the short arm of chromosome 6. In the present study, we use QTL methods to evaluate linkage to the 6p25-21.3 region in a sample of 181 sib pairs from 82 nuclear families that were selected on the basis of a dyslexic proband. We have assessed linkage directly for several quantitative measures that should correlate with different components of the phenotype, rather than using a single composite measure or employing categorical definitions of subtypes. Our measures include the traditional IQ/reading discrepancy score, as well as tests of word recognition, irregular-word reading, and nonword reading. Pointwise analysis by means of sib-pair trait differences suggests the presence, in 6p21.3, of a QTL influencing multiple components of dyslexia, in particular the reading of irregular words (P=.0016) and nonwords (P=.0024). A complementary statistical approach involving estimation of variance components supports these findings (irregular words, P=.007; nonwords, P=.0004). Multipoint analyses place the QTL within the D6S422-D6S291 interval, with a peak around markers D6S276 and D6S105 consistently identified by approaches based on trait differences (irregular words, P=.00035; nonwords, P=.0035) and variance components (irregular words, P=.007; nonwords, P=.0038). Our findings indicate that the QTL affects both phonological and orthographic skills and is not specific to phoneme awareness, as has been previously suggested. Further studies will be necessary to obtain a more precise localization of this QTL, which may lead to the isolation of one of the genes involved in developmental dyslexia.

Abstract

A significant number of individuals have unexplained difficulties with acquiring normal speech and language, despite adequate intelligence and environmental stimulation. Although developmental disorders of speech and language are heritable, the genetic basis is likely to involve several, possibly many, different risk factors. Investigations of a unique three-generation family showing monogenic inheritance of speech and language deficits led to the isolation of the first such gene on chromosome 7, which encodes a transcription factor known as FOXP2. Disruption of this gene causes a rare severe speech and language disorder but does not appear to be involved in more common forms of language impairment. Recent genome-wide scans have identified at least four chromosomal regions that may harbor genes influencing the latter, on chromosomes 2, 13, 16, and 19. The molecular genetic approach has potential for dissecting neurological pathways underlying speech and language disorders, but such investigations are only just beginning.

Abstract

The human Xp11.23-p11.22 interval has been implicated in several inherited diseases including Wiskott-Aldrich syndrome; three forms of X-linked hypercalciuric nephrolithiaisis; and the eye disorders retinitis pigmentosa 2, congenital stationary night blindness, and Aland Island eye disease. In constructing YAC contigs spanning Xp11. 23-p11.22, we have previously shown that the region around the synaptophysin (SYP) gene is refractory to cloning in YACs, but highly stable in cosmids. Preliminary analysis of the latter suggested that this might reflect a high density of coding sequences and we therefore undertook the complete sequencing of a SYP-containing cosmid. Sequence data were extensively analyzed using computer programs such as CENSOR (to mask repeats), BLAST (for homology searches), and GRAIL and GENE-ID (to predict exons). This revealed the presence of 29 putative exons, organized into three genes, in addition to the 7 exons of the complete SYP coding region, all mapping within a 44-kb interval. Two genes are novel, one (CACNA1F) showing high homology to alpha1 subunits of calcium channels, the other (LMO6) encoding a product with significant similarity to LIM-domain proteins. RT-PCR and Northern blot studies confirmed that these loci are indeed transcribed. The third locus is the previously described, but not previously localized, A4 differentiation-dependent gene. Given that the intron-exon boundaries predicted by the analysis are consistent with previous information where available, we have been able to suggest the genomic organization of the novel genes with some confidence. The region has an elevated GC content (>53%), and we identified CpG islands associated with the 5' ends of SYP, A4, and LMO6. The order of loci was Xpter-A4-LMO6-SYP-CACNA1F-Xcen, with intergenic distances ranging from approximately 300 bp to approximately 5 kb. The density of transcribed sequences in this area (>80%) is comparable to that found in the highly gene-rich chromosomal band Xq28. Further studies may aid our understanding of the long-range organization surrounding such gene-enriched regions.

Abstract

Research on pattern perception and rule learning, grounded in formal language theory (FLT) and using artificial grammar learning paradigms, has exploded in the last decade. This approach marries empirical research conducted by neuroscientists, psychologists and ethologists with the theory of computation and FLT, developed by mathematicians, linguists and computer scientists over the last century. Of particular current interest are comparative extensions of this work to non-human animals, and neuroscientific investigations using brain imaging techniques. We provide a short introduction to the history of these fields, and to some of the dominant hypotheses, to help contextualize these ongoing research programmes, and finally briefly introduce the papers in the current issue.

Abstract

No abstract is available for this article

Abstract

Understanding the progression of neurological diseases is vital for accurate and early diagnosis and treatment planning. We introduce a new characterization of disease progression, which describes the disease as a series of events, each comprising a significant change in patient state. We provide novel algorithms to learn the event ordering from heterogeneous measurements over a whole patient cohort and demonstrate using combined imaging and clinical data from familial-Alzheimer's and Huntington's disease cohorts. Results provide new detail in the progression pattern of these diseases, while confirming known features, and give unique insight into the variability of progression over the cohort. The key advantage of the new model and algorithms over previous progression models is that they do not require a priori division of the patients into clinical stages. The model and its formulation extend naturally to a wide range of other diseases and developmental processes and accommodate cross-sectional and longitudinal input data.