1-9 of 9 Results

  • Keywords: models x
Clear all

Article

Speech production is an important aspect of linguistic competence. An attempt to understand linguistic morphology without speech production would be incomplete. A central research question develops from this perspective: what is the role of morphology in speech production. Speech production researchers collect many different types of data and much of that data has informed how linguists and psycholinguists characterize the role of linguistic morphology in speech production. Models of speech production play an important role in the investigation of linguistic morphology. These models provide a framework, which allows researchers to explore the role of morphology in speech production. However, models of speech production generally focus on different aspects of the production process. These models are split between phonetic models (which attempt to understand how the brain creates motor commands for uttering and articulating speech) and psycholinguistic models (which attempt to understand the cognitive processes and representation of the production process). Models that merge these two model types, phonetic and psycholinguistic models, have the potential to allow researchers the possibility to make specific predictions about the effects of morphology on speech production. Many studies have explored models of speech production, but the investigation of the role of morphology and how morphological properties may be represented in merged speech production models is limited.

Article

There are two main theoretical traditions in semantics. One is based on realism, where meanings are described as relations between language and the world, often in terms of truth conditions. The other is cognitivistic, where meanings are identified with mental structures. This article presents some of the main ideas and theories within the cognitivist approach. A central tenet of cognitively oriented theories of meaning is that there are close connections between the meaning structures and other cognitive processes. In particular, parallels between semantics and visual processes have been studied. As a complement, the theory of embodied cognition focuses on the relation between actions and components of meaning. One of the main methods of representing cognitive meaning structures is to use images schemas and idealized cognitive models. Such schemas focus on spatial relations between various semantic elements. Images schemas are often constructed using Gestalt psychological notions, including those of trajector and landmark, corresponding to figure and ground. In this tradition, metaphors and metonymies are considered to be central meaning transforming processes. A related approach is force dynamics. Here, the semantic schemas are construed from forces and their relations rather than from spatial relations. Recent extensions involve cognitive representations of actions and events, which then form the basis for a semantics of verbs. A third approach is the theory of conceptual spaces. In this theory, meanings are represented as regions of semantic domains such as space, time, color, weight, size, and shape. For example, strong evidence exists that color words in a large variety of languages correspond to such regions. This approach has been extended to a general account of the semantics of some of the main word classes, including adjectives, verbs, and prepositions. The theory of conceptual spaces shows similarities to the older frame semantics and feature analysis, but it puts more emphasis on geometric structures. A general criticism against cognitive theories of semantics is that they only consider the meaning structures of individuals, but neglect the social aspects of semantics, that is, that meanings are shared within a community. Recent theoretical proposals counter this by suggesting that semantics should be seen as a meeting of minds, that is, communicative processes that lead to the alignment of meanings between individuals. On this approach, semantics is seen as a product of communication, constrained by the cognitive mechanisms of the individuals.

Article

Patrice Speeter Beddor

In their conversational interactions with speakers, listeners aim to understand what a speaker is saying, that is, they aim to arrive at the linguistic message, which is interwoven with social and other information, being conveyed by the input speech signal. Across the more than 60 years of speech perception research, a foundational issue has been to account for listeners’ ability to achieve stable linguistic percepts corresponding to the speaker’s intended message despite highly variable acoustic signals. Research has especially focused on acoustic variants attributable to the phonetic context in which a given phonological form occurs and on variants attributable to the particular speaker who produced the signal. These context- and speaker-dependent variants reveal the complex—albeit informationally rich—patterns that bombard listeners in their everyday interactions. How do listeners deal with these variable acoustic patterns? Empirical studies that address this question provide clear evidence that perception is a malleable, dynamic, and active process. Findings show that listeners perceptually factor out, or compensate for, the variation due to context yet also use that same variation in deciding what a speaker has said. Similarly, listeners adjust, or normalize, for the variation introduced by speakers who differ in their anatomical and socio-indexical characteristics, yet listeners also use that socially structured variation to facilitate their linguistic judgments. Investigations of the time course of perception show that these perceptual accommodations occur rapidly, as the acoustic signal unfolds in real time. Thus, listeners closely attend to the phonetic details made available by different contexts and different speakers. The structured, lawful nature of this variation informs perception. Speech perception changes over time not only in listeners’ moment-by-moment processing, but also across the life span of individuals as they acquire their native language(s), non-native languages, and new dialects and as they encounter other novel speech experiences. These listener-specific experiences contribute to individual differences in perceptual processing. However, even listeners from linguistically homogenous backgrounds differ in their attention to the various acoustic properties that simultaneously convey linguistically and socially meaningful information. The nature and source of listener-specific perceptual strategies serve as an important window on perceptual processing and on how that processing might contribute to sound change. Theories of speech perception aim to explain how listeners interpret the input acoustic signal as linguistic forms. A theoretical account should specify the principles that underlie accurate, stable, flexible, and dynamic perception as achieved by different listeners in different contexts. Current theories differ in their conception of the nature of the information that listeners recover from the acoustic signal, with one fundamental distinction being whether the recovered information is gestural or auditory. Current approaches also differ in their conception of the nature of phonological representations in relation to speech perception, although there is increasing consensus that these representations are more detailed than the abstract, invariant representations of traditional formal phonology. Ongoing work in this area investigates how both abstract information and detailed acoustic information are stored and retrieved, and how best to integrate these types of information in a single theoretical model.

Article

Corpora are an all-important resource in linguistics, as they constitute the primary source for large-scale examples of language usage. This has been even more evident in recent years, with the increasing availability of texts in digital format leading more and more corpus linguistics toward a “big data” approach. As a consequence, the quantitative methods adopted in the field are becoming more sophisticated and various. When it comes to morphology, corpora represent a primary source of evidence to describe morpheme usage, and in particular how often a particular morphological pattern is attested in a given language. There is hence a tight relation between corpus linguistics and the study of morphology and the lexicon. This relation, however, can be considered bi-directional. On the one hand, corpora are used as a source of evidence to develop metrics and train computational models of morphology: by means of corpus data it is possible to quantitatively characterize morphological notions such as productivity, and corpus data are fed to computational models to capture morphological phenomena at different levels of description. On the other hand, morphology has also been applied as an organization principle to corpora. Annotations of linguistic data often adopt morphological notions as guidelines. The resulting information, either obtained from human annotators or relying on automatic systems, makes corpora easier to analyze and more convenient to use in a number of applications.

Article

Computational models of human sentence comprehension help researchers reason about how grammar might actually be used in the understanding process. Taking a cognitivist approach, this article relates computational psycholinguistics to neighboring fields (such as linguistics), surveys important precedents, and catalogs open problems.

Article

Marianne Pouplier

One of the most fundamental problems in research on spoken language is to understand how the categorical, systemic knowledge that speakers have in the form of a phonological grammar maps onto the continuous, high-dimensional physical speech act that transmits the linguistic message. The invariant units of phonological analysis have no invariant analogue in the signal—any given phoneme can manifest itself in many possible variants, depending on context, speech rate, utterance position and the like, and the acoustic cues for a given phoneme are spread out over time across multiple linguistic units. Speakers and listeners are highly knowledgeable about the lawfully structured variation in the signal and they skillfully exploit articulatory and acoustic trading relations when speaking and perceiving. For the scientific description of spoken language understanding this association between abstract, discrete categories and continuous speech dynamics remains a formidable challenge. Articulatory Phonology and the associated Task Dynamic model present one particular proposal on how to step up to this challenge using the mathematics of dynamical systems with the central insight being that spoken language is fundamentally based on the production and perception of linguistically defined patterns of motion. In Articulatory Phonology, primitive units of phonological representation are called gestures. Gestures are defined based on linear second order differential equations, giving them inherent spatial and temporal specifications. Gestures control the vocal tract at a macroscopic level, harnessing the many degrees of freedom in the vocal tract into low-dimensional control units. Phonology, in this model, thus directly governs the spatial and temporal orchestration of vocal tract actions.

Article

Connectionism is an important theoretical framework for the study of human cognition and behavior. Also known as Parallel Distributed Processing (PDP) or Artificial Neural Networks (ANN), connectionism advocates that learning, representation, and processing of information in mind are parallel, distributed, and interactive in nature. It argues for the emergence of human cognition as the outcome of large networks of interactive processing units operating simultaneously. Inspired by findings from neural science and artificial intelligence, connectionism is a powerful computational tool, and it has had profound impact on many areas of research, including linguistics. Since the beginning of connectionism, many connectionist models have been developed to account for a wide range of important linguistic phenomena observed in monolingual research, such as speech perception, speech production, semantic representation, and early lexical development in children. Recently, the application of connectionism to bilingual research has also gathered momentum. Connectionist models are often precise in the specification of modeling parameters and flexible in the manipulation of relevant variables in the model to address relevant theoretical questions, therefore they can provide significant advantages in testing mechanisms underlying language processes.

Article

Jane Chandlee and Jeffrey Heinz

Computational phonology studies the nature of the computations necessary and sufficient for characterizing phonological knowledge. As a field it is informed by the theories of computation and phonology. The computational nature of phonological knowledge is important because at a fundamental level it is about the psychological nature of memory as it pertains to phonological knowledge. Different types of phonological knowledge can be characterized as computational problems, and the solutions to these problems reveal their computational nature. In contrast to syntactic knowledge, there is clear evidence that phonological knowledge is computationally bounded to the so-called regular classes of sets and relations. These classes have multiple mathematical characterizations in terms of logic, automata, and algebra with significant implications for the nature of memory. In fact, there is evidence that phonological knowledge is bounded by particular subregular classes, with more restrictive logical, automata-theoretic, and algebraic characterizations, and thus by weaker models of memory.

Article

Ocke-Schwen Bohn

The study of second language phonetics is concerned with three broad and overlapping research areas: the characteristics of second language speech production and perception, the consequences of perceiving and producing nonnative speech sounds with a foreign accent, and the causes and factors that shape second language phonetics. Second language learners and bilinguals typically produce and perceive the sounds of a nonnative language in ways that are different from native speakers. These deviations from native norms can be attributed largely, but not exclusively, to the phonetic system of the native language. Non-nativelike speech perception and production may have both social consequences (e.g., stereotyping) and linguistic–communicative consequences (e.g., reduced intelligibility). Research on second language phonetics over the past ca. 30 years has resulted in a fairly good understanding of causes of nonnative speech production and perception, and these insights have to a large extent been driven by tests of the predictions of models of second language speech learning and of cross-language speech perception. It is generally accepted that the characteristics of second language speech are predominantly due to how second language learners map the sounds of the nonnative to the native language. This mapping cannot be entirely predicted from theoretical or acoustic comparisons of the sound systems of the languages involved, but has to be determined empirically through tests of perceptual assimilation. The most influential learner factors which shape how a second language is perceived and produced are the age of learning and the amount and quality of exposure to the second language. A very important and far-reaching finding from research on second language phonetics is that age effects are not due to neurological maturation which could result in the attrition of phonetic learning ability, but to the way phonetic categories develop as a function of experience with surrounding sound systems.