No impairment in sign language after right-hemisphere stroke

A 52-year-old right-handed woman who became deaf before the development of speech, suffered an occlusion of the right middle cerebral and a marked stenosis of the right anterior cerebral arteries. She showed no disturbance in the manual sign language or in finger-spelling, in contrast to previous reports of cases with left-sided damage.     

语言认知老化机制及其神经基础

老龄化个体出现的认知障碍在某种程度上是由于语言的认知老化所导致,因此,了解语言认知老化的具体表现、老化机制及其神经基础对于延缓语言认知老化、矫正老年痴呆有重要意义。首先基于理解和产生两个维度,分别从词汇、句子和文本三个层面分析了语言认知老化的表现,而后着重从工作记忆的角度分析了语言认知老化的认知机制,在此基础上,进一步从词汇加工、语义提取、句法分析三个方面分析了语言认知老化的神经基础,并指出半球不对称性减弱和脑区的弥散性激活是语言认知老化的主要神经表现。最后,围绕着语言认知老化的"发展进程、领域表现形式、干预矫正方法"三个必须解决的问题展开讨论,为该领域未来的发展做出理论上的铺垫。     

The molecular basis of cognitive deficits in pervasive developmental disorders

Persons with pervasive developmental disorders (PDD) exhibit a range of cognitive deficits that hamper their quality of life, including difficulties involving communication, sociability, and perspective-taking. In recent years, a variety of studies in mice that model genetic syndromes with a high risk of PDD have provided insights into the underlying molecular mechanisms associated with these disorders. What is less appreciated is how the molecular anomalies affect neuronal and circuit function to give rise to the cognitive deficits associated with PDD. In this review, we describe genetic mutations that cause PDD and discuss how they alter fundamental social and cognitive processes. We then describe efforts to correct cognitive impairments associated with these disorders and identify areas of further inquiry in the search for molecular targets for therapeutics for PDD.     

A pragmatic description of early language development

Language acquisition involves more than learning the abstract structures of linguistic competence. The child also has to learn how to use linguistic structures appropriately. In this paper, the speech act is proposed as the unit of analysis for studying the pragmatics of early child language. The results of a study of children's uses of single-word utterances are reported, and the data are analyzed in terms of “primitive speech acts.”     

A pragmatic perspective of repetition in child language

The contention that repetition may be used for a variety of communicative functions is supported with data from a longitudinal study of one child. Repetitions were identified from videotapes and then classified according to the communicative function being expressed. Additionally, discourse profiles were identified for various communicative functions being expressed via repetition.     

Communicative intentions and language: evidence from right-hemisphere damage and autism.

In this review article, it is argued that the wide range of communicative deficits that have been noted in both individuals with damage to the right cerebral hemisphere (RHD) and high-functioning individuals with autism may stem from difficulties appreciating the importance of their interlocutor's communicative intentions (CIs). It is also argued that the abnormal semantic development noted in infants with RHD and autism may be related to difficulties in appreciating CIs as well. Finally, it is suggested that the CIs hypothesis may provide an avenue for integrating a number of theoretical suggestions that have been made regarding the right hemisphere's contributions to communicative competence.     

Extraction of linguistically relevant pragmatic contrast through language learning

This study explores whether pragmatic contrast that is not expressed as relevant in the subjects' native language is extracted through language learning. Miniature artificial languages were used. In Experiment 1, a contrast was created such that four persons appeared together in each situation, with three persons performing the same activities and the fourth one performing a different target activity. Under this presentation condition pragmatic contrast was shown to be rather easily extracted. In Experiments 2 and 3, a single person appeared in each situation and contrast was created serially by changing the position in which the person performing the target activity was placed. Under these presentation conditions sufficient evidence for the extraction of pragmatic contrast was not found. Experiment 2 also examined the effect of different experience of instances on the extraction of pragmatic contrast. Results showed that although different experience did not produce a differential effect as expected, a definite conclusion was not drawn for a low level of performance. It was formulated that the two presentation conditions differed in the degree of transparency for a mapping relation between the linguistic structure and the pragmatic contrast. Implications of the findings were suggested in relation to a natural learning situation.Deep gratitude is due to Professor D. D. Steinberg for his reading of an earlier version of this paper.     

Exploring the space of cognitive architectures

Production systems have been proposed as a candidate for the basic architecture of the human information processor. We consider a number of dimensions along which production systems can vary, and we discuss PRISM, a production system formalism designed to aid cognitive modelers in their exploration of the space of architectures. Examples of PRISM settings are presented in the context of particular models. Finally, some heuristics are suggested for efficiently searching the space of possible architectures.     

Exploring the nature of cognitive flexibility

Cognitive flexibility is an important characteristic that helps humans pursue complex tasks, such as multitasking and finding novel, adaptable solutions to changing demands. Yet it is still a poorly understood construct. After briefly reviewing several investigations of this construct in cognitive science, I propose a unified account that considers cognitive flexibility a property of the cognitive system, rather than a cognitive skill. The emergence of cognitive flexibility is dependent on two kinds of interactions: the interaction of several cognitive mechanisms, and the interaction of sensorimotor mechanisms, cognition, and context in developmental time. The quest for a comprehensive and unified account of cognitive flexibility is highly justified given its potential usefulness in fostering efficient problem solving and creativity.     

Relevance theory,pragmatic inference and cognitive architecture

Relevance Theory (RT) argues that human language comprehension processes tend to maximize “relevance,” and postulates that there is a relevance-based procedure that a hearer follows when trying to understand an utterance. Despite being highly influential, RT has been criticized for its failure to explain how speaker-related information, either the speaker’s abilities or her/his preferences, is incorporated into the hearer’s inferential, pragmatic process. An alternative proposal is that speaker-related information gains prominence due to representation of the speaker within higher level goal-directed schemata. Yet the goal-based account is still unable to explain clearly how cross-domain information, for example linguistic meaning and speaker-related knowledge, is integrated within a modular system. On the basis of RT’s cognitive requirements, together with contemporary cognitive theory, we argue that this integration is realized by utilizing working memory and that there exist conversational constraints with which the constructed utterance interpretation should be consistent. We illustrate our arguments with a computational implementation of the proposed processes within a general cognitive architecture.

Abbreviations: ACT-R Adaptive Control of Thought - RationalCOGENT Cognitive Objects within a Graphical ENvironmenTCS/SS Contention Scheduling/Supervisory SystemRBCP Relevance-Based Comprehension ProcedureRT Relevance Theory     

The cognitive functions of language

This paper explores a variety of different versions of the thesis that natural language is involved in human thinking. It distinguishes amongst strong and weak forms of this thesis, dismissing some as implausibly strong and others as uninterestingly weak. Strong forms dismissed include the view that language is conceptually necessary for thought (endorsed by many philosophers) and the view that language is de facto the medium of all human conceptual thinking (endorsed by many philosophers and social scientists). Weak forms include the view that language is necessary for the acquisition of many human concepts and the view that language can serve to scaffold human thought processes. The paper also discusses the thesis that language may be the medium of conscious propositional thinking, but argues that this cannot be its most fundamental cognitive role. The idea is then proposed that natural language is the medium for nondomain-specific thinking, serving to integrate the outputs of a variety of domain-specific conceptual faculties (or central-cognitive "quasimodules"). Recent experimental evidence in support of this idea is reviewed and the implications of the idea are discussed, especially for our conception of the architecture of human cognition. Finally, some further kinds of evidence which might serve to corroborate or refute the hypothesis are mentioned. The overall goal of the paper is to review a wide variety of accounts of the cognitive function of natural language, integrating a number of different kinds of evidence and theoretical consideration in order to propose and elaborate the most plausible candidate.     

The cognitive basis of the Uznadze illusion

The present study examines the role of Luria's dimensions of simultaneous and successive synthesis in fixation and extinction of the Uznadze haptic illusion. The subjects were 53 grade 10 high school students. Extinction of the illusion correlated significantly with three measures which, according to Luria's criteria, are indicative of simultaneous synthesis. Correlations between extinction and measures of successive synthesis failed to reach significance. Fixation of the illusion was unrelated to measures of either simultaneous or successive synthesis. An exploratory factor analysis of the data suggested the hypothesis that extinction of the illusion is greatly facilitated when the successive presentations of the spheres are integrated into a simultaneous or contemporaneous pattern.     

Inhibition and language pragmatic view in redundant data problem solving

The present study concerns redundant data problems, defined as problems in which irrelevant data is provided. This type of problem provides a misleading context [Pascual-Leone, J. (1987). Organismic process for neo-Piagetian theories: A dialectical causal account of cognitive development. International Journal of Psychology, 22, 531–570] similar to the Piagetian class inclusion task. The two experiments performed showed that adding the a-pragmatic cue ‘in total’ to the final question of redundant data problems increased both 7- and 9-year-old children's failure rate, without modifying the structure of the problem. This indicates that a non-structural linguistic cue can bias children towards failure by enhancing the lack of inhibition of the ordinary adding schema.     

Genes, language development, and language disorders

Genetic factors are important contributors to language and learning disorders, and discovery of the underlying genes can help delineate the basic neurological pathways that are involved. This information, in turn, can help define disorders and their perceptual and processing deficits. Initial molecular genetic studies of dyslexia, for example, appear to converge on defects in neuronal and axonal migration. Further study of individuals with abnormalities of these genes may lead to the recognition of characteristic cognitive deficits attributable to the neurological dysfunction. Such abnormalities may affect other disorders as well, and studies of co-morbidity of dyslexia with attention deficit disorder and speech sound disorder are helping to define the scope of these genes and show the etiological and cognitive commonalities between these conditions. The genetic contributions to specific language impairment (SLI) are not as well defined at this time, but similar molecular approaches are being applied to identify genes that influence SLI and comorbid disorders. While there is co-morbidity of SLI with dyslexia, it appears that most of the common genetic effects may be with the language characteristics of autism spectrum disorders rather than with dyslexia and related disorders. Identification of these genes and their neurological and cognitive effects should lay out a functional network of interacting genes and pathways that subserve language development. Understanding these processes can form the basis for refined procedures for diagnosis and treatment.     

The cognitive neuroscience of signed language

The present article is an assessment of the current state of knowledge in the field of cognitive neuroscience of signed language. Reviewed lesion data show that the left hemisphere is dominant for perception and production of signed language in aphasics, in a fashion similar to spoken language aphasia. Several neuropsychological dissociations support this claim: Non-linguistic visuospatial functions can be dissociated from spatial functions and general motor deficits can be dissociated from execution of signs. Reviewed imaging data corroborate the lesion data in that the importance of the left hemisphere is re-confirmed. The data also establish the role of the right hemisphere in signed language processing. Alternative hypotheses regarding what aspects of signed language processing are handled by the right hemisphere are currently tested. The second section of the paper starts by addressing the role that early acquisition of signed and spoken language play for the neurofunctional activation patterns in the brain. Compensatory cognitive and communicative enhancements have also been documented as a function of early sign language use, suggesting an interesting interaction between language and cognition. Recent behavioural data on sign processing in working memory--a cognitive system important for language perception and production suggest e.g. phonological loop effects analogous to those obtained for speech processing. Neuroimaging studies will have to address this potential communality.