Publications

Abstract

A recurrently connected attractor neural network with a Hebbian learning rule is currently our best ANN analogy for a piece cortex. Functionally biological memory operates on a spectrum of time scales with regard to induction and retention, and it is modulated in complex ways by sub-cortical neuromodulatory systems. Moreover, biological memory networks are commonly believed to be highly distributed and engage many co-operating cortical areas. Here we focus on the temporal aspects of induction and retention of memory in a connectionist type attractor memory model of a piece of cortex. A continuous time, forgetful Bayesian-Hebbian learning rule is described and compared to the characteristics of LTP and LTD seen experimentally. More generally, an attractor network implementing this learning rule can operate as a long-term, intermediate-term, or short-term memory. Modulation of the print-now signal of the learning rule replicates some experimental memory phenomena, like e.g. the von Restorff effect.

Abstract

Evolution and changes of all modern languages is a wellknown fact. However, recently it is reaching dynamics never seen before, which results in loss of the vast amount of information encoded in every language. In order to preserve such rich heritage, and to carry out linguistic research, properly annotated recordings of world languages are necessary. Since creating those annotations is a very laborious task, reaching times 100 longer than the length of the annotated media, innovative video processing algorithms are needed, in order to improve the efficiency and quality of annotation process. This is the scope of the AVATecH project presented in this article

Abstract

People's language is shaped by the input from the environment. The environment, however, offers a range of linguistic inputs that differ in their reliability. We test whether listeners accordingly weigh input from sources that differ in reliability differently. Using a perceptual learning paradigm, we show that listeners adjust their representations according to linguistic input provided by native but not by non-native speakers. This is despite the fact that listeners are able to learn the characteristics of the speech of both speakers. These results provide evidence for a disassociation between adaptation to the characteristic of specific speakers and adjustment of linguistic representations in general based on these learned characteristics. This study also has implications for theories of language change. In particular, it cast doubts on the hypothesis that a large proportion of non-native speakers in a community can bring about linguistic changes

Abstract

There has been a recent spate of work on recursion as a central design feature of language and specifically of syntax. This short report points out that there is little evidence that unlimited recursion, understood as centre embedding, is typical of natural language syntax. Nevertheless, embedded pragmatic construals seem available in every language. Further, much deeper centre embedding can be found in dialogue or conversation structure than can be found in syntax. Existing accounts for the ‘performance’ limitations on centre embedding are thus thrown in doubt. Dialogue materials suggest that centre embedding is perhaps a core part of the human interaction system and is for some reason much more highly restricted in syntax than in other aspects of cognition

Abstract

This study investigates prosodic marking of focus in Bai, a Sino-Tibetan language spoken in the Southwest of China, by adopting a semi-spontaneous experimental approach. Our data show that Bai speakers increase the duration of the focused constituent and reduce the duration of the post-focus constituent to encode focus. However, duration is not used in Bai to distinguish focus types differing in size and contrastivity. Further, pitch plays no role in signaling focus and differentiating focus types. The results thus suggest that Bai uses prosody to mark focus, but to a lesser extent, compared to Mandarin Chinese, with which Bai has been in close contact for centuries, and Cantonese, to which Bai is similar in the tonal system, although Bai is similar to Cantonese in its reliance on duration in prosodic focus marking.

Abstract

The human body is unique: it is both an object of perception and the source of human experience. Its universality makes it a perfect resource for asking questions about how cognition, brain and typology relate to one another. For example, we can ask how speakers of different languages segment and categorize the human body. A dominant view is that body parts are “given” by visual perceptual discontinuities, and that words are merely labels for these visually determined parts (e.g., Andersen, 1978; Brown, 1976; Lakoff, 1987). However, there are problems with this view. First it ignores other perceptual information, such as somatosensory and motoric representations. By looking at the neural representations of sesnsory representations, we can test how much of the categorization of the human body can be done through perception alone. Second, we can look at language typology to see how much universality and variation there is in body-part categories. A comparison of a range of typologically, genetically and areally diverse languages shows that the perceptual view has only limited applicability (Majid, Enfield & van Staden, in press). For example, using a “coloring-in” task, where speakers of seven different languages were given a line drawing of a human body and asked to color in various body parts, Majid & van Staden (in prep) show that languages vary substantially in body part segmentation. For example, Jahai (Mon-Khmer) makes a lexical distinction between upper arm, lower arm, and hand, but Lavukaleve (Papuan Isolate) has just one word to refer to arm, hand, and leg. This shows that body part categorization is not a straightforward mapping of words to visually determined perceptual parts.

Abstract

Many studies in cognitive science address how people categorize objects, but there has been comparatively little research on event categorization. This study investigated the categorization of events involving material destruction, such as “cutting” and “breaking”. Speakers of 28 typologically, genetically, and areally diverse languages described events shown in a set of video-clips. There was considerable cross-linguistic agreement in the dimensions along which the events were distinguished, but there was variation in the number of categories and the placement of their boundaries.

Abstract

Models are a flourishing and indispensable area of research in language evolution. Here we
highlight critical issues in using and interpreting models, and suggest viable approaches. First,
contrasting models can explain the same data and similar modelling techniques can lead to
diverging conclusions. This should act as a reminder to use the extreme malleability of
modelling parsimoniously when interpreting results. Second, quantitative techniques similar to
those used in modelling language evolution have proven themselves inadequate in other
disciplines. Cross-disciplinary fertilization is crucial to avoid mistakes which have previously
occurred in other areas. Finally, experimental validation is necessary both to sharpen models'
hypotheses, and to support their conclusions. Our belief is that models should be interpreted as
quantitative demonstrations of logical possibilities, rather than as direct sources of evidence.
Only an integration of theoretical principles, quantitative proofs and empirical validation can
allow research in the evolution of language to progress.

Abstract

Two Siberian languages, Tundra Nenets and Tundra Yukaghir, do not obey strong island constraints in questioning: any sub-constituent of a relative or adverbial clause can be questioned. We argue that this has to do with how focusing works in these languages. The focused sub-constituent remains in situ, but there is abundant morphosyntactic evidence that the focus feature is passed up to the head of the clause. The result is the formation of a complex focus structure in which both the head and non head daughter are overtly marked as focus, and they are interpreted as a pairwise list such that the focus background is applicable to this list, but not to other alternative lists

Abstract

This volume is dedicated to exploring the crossroads where complex sentences and information management – more specifically information structure (IS) and reference tracking (RT) – come together. Complex sentences are a highly relevant but understudied domain for studying notions of IS and RT. On the one hand, a complex sentence can be studied as a mini-unit of discourse consisting of two or more elements describing events, situations, or processes, with its own internal information-structural and referential organisation. On the other hand, complex sentences can be studied as parts of larger discourse structures, such as narratives or conversations, in terms of how their information-structural characteristics relate to this wider context.We first focus on the interrelatedness of IS and RT (Section 1) and then define and discuss the notion of complex sentences and their subtypes in Section 2. Section 3 surveys issues of IS in complex sentences, while Section 4 focuses on RT in complex sentences. Sections 5 and 6 briefly consider IS and RT in a wider discourse context. Section 5 discusses the interaction between IS, RT, and other discourse factors, and Section 6 focuses on ways in which a specific RT system, switch reference, can function as an RT device beyond the sentence.

Abstract

No island effects are observable in Tundra Yukaghir questions, which are possible in virtually all syntactic environments. It is argued that this feature of Tundra Yukaghir relates to its capability of explicitly marking focus domains. If a question word occurs in a syntactic island, the whole island is morphologically treated as a focus domain. In order to take scope and function as question markers, question words must remain within the focus domain, i.e. in the island clause. This syntactic configuration is reflected in the semantics of question islands, which are used to inquire about the identity of the whole island, not merely the denotation of the question word.

Abstract

The results of a word-spotting experiment are presented in which Dutch listeners tried to spot different types of bisyllabic Dutch words embedded in different types of nonsense contexts. Embedded verbs were not reliably harder to spot than embedded nouns; this suggests that nouns and verbs are recognised via the same basic processes. Iambic words were no harder to spot than trochaic words, suggesting that trochaic words are not in principle easier to recognise than iambic words. Words were harder to spot in consonantal contexts (i.e., contexts which themselves could not be words) than in longer contexts which contained at least one vowel (i.e., contexts which, though not words, were possible words of Dutch). A control experiment showed that this difference was not due to acoustic differences between the words in each context. The results support the claim that spoken-word recognition is sensitive to the viability of sound sequences as possible words.

Abstract

Lexical knowledge influences how human listeners make decisions about speech sounds. Positive lexical effects (faster responses to target sounds in words than in nonwords) are robust across several laboratory tasks, while negative effects (slower responses to targets in more word-like nonwords than in less word-like nonwords) have been found in phonetic decision tasks but not phoneme monitoring tasks. The present experiments tested whether negative lexical effects are therefore a task-specific consequence of the forced choice required in phonetic decision. We compared phoneme monitoring and phonetic decision performance using the same Dutch materials in each task. In both experiments there were positive lexical effects, but no negative lexical effects. We observe that in all studies showing negative lexical effects, the materials were made by cross-splicing, which meant that they contained perceptual evidence supporting the lexically-consistent phonemes. Lexical knowledge seems to influence phonemic decision-making only when there is evidence for the lexically-consistent phoneme in the speech signal.

Abstract

We briefly describe the Merge model of phonemic decision-making, and, in the light of general arguments about the possible role of feedback in spoken-word recognition, defend Merge's feedforward structure. Merge not only accounts adequately for the data, without invoking feedback connections, but does so in a parsimonious manner.

Abstract

In this paper, we present two attempts to replicate a widely-cited but never fully published experiment in which German and Spanish speakers were asked to associate adjectives with nouns of masculine and feminine grammati-cal gender (Boroditsky et al. 2003). The researchers claim that speakers associ-ated more stereotypically female adjectives with grammatically feminine nouns and more stereotypically male adjectives with grammatically masculine nouns. We were not able to replicate the results either in a word association task or in an analogous primed lexical decision task. This suggests that the results of the original experiment were either an artifact of some non-documented aspect of the experimental procedure or a statistical fluke. The question whether speakers assign sex-based interpretations to grammatical gender categories at all cannot be answered definitively, as the results in the published literature vary consider-ably. However, our experiments show that if such an effect exists, it is not strong enough to be measured indirectly via the priming of adjectives by nouns.

Abstract

This paper describes the pilot study of phonetic segmentation applied to Nijmegen Corpus of Casual Czech (NCCCz). This corpus contains informal speech of strong spontaneous nature which influences the character of produced speech at various levels. This work is the part of wider research related to the analysis of pronunciation reduction in such informal speech. We present the analysis of the accuracy of phonetic segmentation when canonical or reduced pronunciation is used. The achieved accuracy of realized phonetic segmentation provides information about general accuracy of proper acoustic modelling which is supposed to be applied in spontaneous speech recognition. As a byproduct of presented spontaneous speech segmentation, this paper also describes the created lexicon with canonical pronunciations of words in NCCCz, a tool supporting pronunciation check of lexicon items, and finally also a minidatabase of selected utterances from NCCCz manually labelled on phonetic level suitable for evaluation purposes

Abstract

Effekte linguisticher Typologie auf die Sprach-entwicklung. In G. Plehn (Ed.), Jahrbuch der Max-Planck Gesellsch

Abstract

The human language processor is conceived as a system that consists of several interrelated subsystems. Each subsystem performs a specific task in the complex process of language comprehension and production. A subsystem receives a particular input, performs certain specific operations on this input and yields a particular output. The subsystems can be characterized in terms of the transformations that relate the input representations to the output representations. An important issue in describing the language processing system is to identify the subsystems and to specify the relations between the subsystems. These relations can be conceived in two different ways. In one conception the subsystems are autonomous. They are related to each other only by the input-output channels. The operations in one subsystem are not affected by another system. The subsystems are modular, that is they are independent. In the other conception, the different subsystems influence each other. A subsystem affects the processes in another subsystem. In this conception there is an interaction between the subsystems.

Abstract

Two word-spotting experiments are reported that examine whether the Possible-Word Constraint (PWC) [1] is a language-specific or language-universal strategy for the segmentation of continuous speech. The PWC disfavours parses which leave an impossible residue between the end of a candidate word and a known boundary. The experiments examined cases where the residue was either a CV syllable with a lax vowel, or a CVC syllable with a schwa. Although neither syllable context is a possible word in English, word-spotting in both contexts was easier than with a context consisting of a single consonant. The PWC appears to be language-universal rather than language-specific.

Abstract

Simulations explored the inability of the TRACE model of spoken-word recognition to model the effects on human listening of subcategorical mismatch in word forms. The source of TRACE's failure lay not in interactive connectivity, not in the presence of inter-word competition, and not in the use of phonemic representations, but in the need for continuously optimised interpretation of the input. When an analogue of TRACE was allowed to cycle to asymptote on every slice of input, an acceptable simulation of the subcategorical mismatch data was achieved. Even then, however, the simulation was not as close as that produced by the Merge model, which has inter-word competition, phonemic representations and continuous optimisation (but no interactive connectivity).

Abstract

Early studies investigating sign language acquisition claimed
that signs whose structures are motivated by the form of their
referent (iconic) are not favoured in language development.
However, recent work has shown that the first signs in deaf
children’s lexicon are iconic. In this paper we go a step
further and ask whether different types of iconicity modulate
learning sign-referent links. Results from a picture description
task indicate that children and adults used signs with two
possible variants differentially. While children signing to
adults favoured variants that map onto actions associated with
a referent (action signs), adults signing to another adult
produced variants that map onto objects’ perceptual features
(perceptual signs). Parents interacting with children used
more action variants than signers in adult-adult interactions.
These results are in line with claims that language
development is tightly linked to motor experience and that
iconicity can be a communicative strategy in parental input.

Abstract

A database is presented of relative familiarity ratings for 24 sets of Japanese words, each set comprising words overlapping in the initial portions. These ratings are useful for the generation of material sets for research in the recognition of spoken words.

Abstract

Iconic gestures are hypothesized to be c rucial to the evolution of language. Yet the important question of whether apes produce iconic gestures is the subject of considerable debate. This paper presents the current state of research on iconicity in ape gesture. In particular, it describes some of the empirical evidence suggesting that apes produce three different kinds of iconic gestures; it compares the iconicity hypothesis to other major hypotheses of ape gesture; and finally, it offers some directions for future ape gesture research

Abstract

This chapter describes topic management in the Papuan language Usan. The notion of ‘topic’ is defined by its pre-theoretical meaning ‘what someone’s speech is about’. This notion cannot be restricted to simple clausal or sentential constructions, but requires the wider context of long stretches of natural text. The tracking of a topic is examined in its relationship to clause combining mechanisms. Coordinating clause chaining with its switch reference mechanism is contrasted with subordinating strategies called ‘domain-creating’ constructions. These different strategies are identified by language-specific signals, such as intonation and morphosyntactic cues like nominalizations and scope of negation and other modalities.

Abstract

Dediu and Levinson (2013) argue that Neandertals had essentially modern language and speech, and that they were in genetic contact with the ancestors of modern humans during our dispersal out of Africa. This raises the possibility of cultural and linguistic contact between the two human lineages. If such contact did occur, then it might have influenced the cultural evolution of the languages. Since the genetic traces of contact with Neandertals are limited to the populations outside of Africa, Dediu & Levinson predict that there may be structural differences between the present-day languages derived from languages in contact with Neanderthals, and those derived from languages that were not influenced by such contact. Since the signature of such deep contact might reside in patterns of features, they suggested that machine learning methods may be able to detect these differences. This paper attempts to test this hypothesis and to estimate particular linguistic features that are potential candidates for carrying a signature of Neandertal languages.

Abstract

Complex communication can take place in a range of modalities such as auditory, visual, and tactile modalities. In a very general way, the modality that individuals use is constrained by their biological biases (humans cannot use magnetic fields directly to communicate to each other). The majority of natural languages have a large audible component. However, since humans can learn sign languages just as easily, it’s not clear to what extent the prevalence of spoken languages is due to biological biases, the social environment or cultural inheritance. This paper suggests that we can explore the relative contribution of these factors by modelling the spontaneous emergence of sign languages that are shared by the deaf and hearing members of relatively isolated communities. Such shared signing communities have arisen in enclaves around the world and may provide useful insights by demonstrating how languages evolve as the deaf proportion of its members has strong biases towards the visual language modality. In this paper we describe a model of cultural evolution in two modalities, combining aspects that are thought to impact the emergence of sign languages in a more general evolutionary framework. The model can be used to explore hypotheses about how sign languages emerge.

Abstract

Recent research suggests that the evolution of language is affected by the inductive biases of its learners. I suggest that there is an implicit assumption that one of these biases is to expect a single linguistic system in the input. Given the prevalence of bilingual cultures, this may not be a valid abstraction. This is illustrated by demonstrating that the ‘minimal naming game’ model, in which a shared lexicon evolves in a population of agents, includes an implicit mutual exclusivity bias. Since recent research suggests that children raised in bilingual cultures do not exhibit mutual exclusivity, the individual learning algorithm of the agents is not as abstract as it appears to be. A modification of this model demonstrates that communicative success can be achieved without mutual exclusivity. It is concluded that complex cultural phenomena, such as bilingualism, do not necessarily result from complex individual learning mechanisms. Rather, the cultural process itself can bring about this complexity.

Abstract

Matsuzawa (2012) presented work at Evolang demonstrating the working memory abilities of chimpanzees. (Inoue & Matsuzawa, 2007) found that chimpanzees can correctly remember the location of 9 randomly arranged numerals displayed for 210ms - shorter than an average human eye saccade. Humans, however, perform poorly at this task. Matsuzawa suggests a semantic link hypothesis: while chimps have good visual, eidetic memory, humans are good at symbolic associations. The extra information in the semantic, linguistic links that humans possess increase the load on working memory and make this task difficult for them. We were interested to see if a wider search could find humans that matched the performance of the chimpanzees. We created an online version of the experiment and challenged people to play. We also attempted to run a non-semantic version of the task to see if this made the task easier. We found that, while humans can perform better than Inoue and Matsuzawa (2007) suggest, chimpanzees can perform better still. We also found no evidence to support the semantic link hypothesis.

Abstract

Models of cultural evolution demonstrate that the link between individual biases and population- level phenomena can be obscured by the process of cultural transmission (Kirby, Dowman, & Griffiths, 2007). However, recent extensions to these models predict that linguistic diversity will not emerge and that learners should evolve to expect little linguistic variation in their input (Smith & Thompson, 2012). We demonstrate that this result derives from assumptions that privilege certain kinds of social interaction by exploring a range of alternative social models. We find several evolutionary routes to linguistic diversity, and show that social interaction not only influences the kinds of biases which could evolve to support language, but also the effects those biases have on a linguistic system. Given the same starting situation, the evolution of biases for language learning and the distribution of linguistic variation are affected by the kinds of social interaction that a population privileges.

Abstract

Although humans are the ultimate “natural language generators”, the area of psycholinguistic modeling has been somewhat underrepresented in recent approaches to Natural Language Generation in computer science. To draw attention to the area and illustrate its potential relevance to Natural Language Generation, I provide an overview of recent work on psycholinguistic modeling of language production together with some key empirical findings, state-of-the-art experimental techniques, and their historical roots. The techniques include analyses of speech-error corpora, chronometric analyses, eyetracking, and neuroimaging.
The overview is built around the issue of cognitive control in natural language generation, concentrating on the production of single words, which is an essential ingredient of the generation of larger utterances. Most of the work exploited the fact that human speakers are good but not perfect at resisting temptation, which has provided some critical clues about the nature of the underlying system.

Abstract

In everyday joint activities (e.g. playing cards, preparing potatoes, collecting empty plates), participants often request others to pass, move or otherwise deploy objects. In order to get these objects to or from the requestee, requesters need to manipulate them, for example by holding them out, reaching for them, or placing them somewhere. As they perform these manual actions, requesters may or may not accompany them with language (e.g. Take this potato and cut it or Pass me your plate). This study shows that adding or omitting language in the design of a request is influenced in the first place by a criterion of recognition. When the requested action is projectable from the advancement of an activity, presenting a relevant object to the requestee is enough for them to understand what to do; when, on the other hand, the requested action is occasioned by a contingent development of the activity, requesters use language to specify what the requestee should do. This criterion operates alongside a perceptual criterion, to do with the affordances of the visual and auditory modality. When the requested action is projectable but the requestee is not visually attending to the requester’s manual behaviour, the requester can use just enough language to attract the requestee’s attention and secure immediate recipiency. This study contributes to a line of research concerned with the organisation of verbal and nonverbal resources for requesting. Focussing on situations in which language is not – or only minimally – used, it demonstrates the role played by visible bodily behaviour and by the structure of everyday activities in the formation and understanding of requests.

Abstract

Most work on competing cues in language acquisition has focussed on what happens when cues compete within a certain construction. There has been far less work on what happens when constructions themselves compete. The aim of the present chapter was to explore how the acquisition mechanism copes when constructions compete in a language. We present three experimental studies, all of which focus on the acquisition of the syntactic function of word order as a marker of the Theme-Recipient relation in ditransitives (form-meaning mapping). In Study 1 we investigated how quickly English children acquire form-meaning mappings when there are two competing structures in the language. We demonstrated that English speaking 4-year- olds, but not 3-year-olds, correctly interpreted both preposition al and double object datives, assigning Theme and Recipient participant roles on the basis of word order cues. There was no advantage for the double object dative despite its greater frequency in child directed speech. In Study 2 we looked at acquisition in a language which has no dative alternation –Welsh–to investigate how quickly children acquire form-meaning mapping when there is no competing structure. We demonstrated that Welsh children (Study 2) acquired the prepositional dative at age 3 years, which was much earlier than English children. Finally, in Study 3 we examined bei2 (give) ditransitives in Cantonese, to investigate what happens when there is no dative alternation (as in Welsh), but when the child hears alternative, and possibly competing, word orders in the input. Like the English 3-year-olds, the Cantonese 3-year-olds had not yet acquired the word order marking constraints of bei2 ditransitives. We conclude that there is not only competition between cues but competition between constructions in language acquisition. We suggest an extension to the competition model (Bates & MacWhinney, 1982) whereby generalisations take place across constructions as easily as they take place within constructions, whenever there are salient similarities to form the basis of the generalisation.