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PubMed1985

Feature-processing deficits following brain injury. I. Overselectivity in recognition memory for compound stimuli.

A previous experiment (S. Wayland & J.E. Taplin, 1982, Brain and Language, 16, 87-108) demonstrated that aphasic subjects had particular difficulty performing a categorization task, which for normals involves abstraction of a prototype from a set of patterns and sorting of other patterns with reference to this prototype. This study extended the investigation to a recognition memory task similarly organized in categorical structure. The aim was to replicate the previous findings and to delineate the precise nature of aphasics' difficulties with such tasks. Aphasics were again found to be aberrant in performing this task in comparison with normal subjects, nonaphasic brain-injured control subjects also demonstrating a departure from normality. The results suggest that the problem for brain-injured subjects is one of overselectivity in terms of the features of the stimuli to which they respond rather than a difficulty with prototype abstraction itself.

Adult↗

PubMed1982

Visual-field differences in picture-word interference.

Picture-word interference refers to the fact that if a picture (i.e., line drawing) is presented centrally with a word superimposed, picture-naming latency is longer than if that same picture is presented alone. This phenomenon, like the Stroop phenomenon, seems to be strongly influenced by the nature of the to-be-ignored word. That is, if the word names a member of the picture's semantic category additional interference is observed; however, if the word is replaced by a phonetically unviable consonant string interference is reduced. In the present experiments these effects were examined in the situation where the picture-word stimuli were presented unilaterally in either the left or right visual field. For right-visual-field presentations, phonetic and semantic factors both influenced performance just as in central presentations. As such, these results can be satisfactorily explained in terms of response competition processes. However, the results for the left-visual-field presentations were quite different. Although substantial interference was observed for all types of stimuli, the amount of interference was essentially independent of the linguistic nature of the superimposed letter string. These results do not appear to be explainable in terms of response competition processes. Instead, it is suggested that the best way to explain these results is in terms of the perceptual capabilities of the right hemisphere.

Cerebral Cortex↗

PubMed1998

To have and to hold: nursing information in the 1990s and beyond.

Within contemporary nursing a tension exists between the need to develop nursing related databases, and the philosophical underpinning of current nursing care. The arguments 'for' include the need to counteract the substitution of nurses by care attendants, the move towards evidence-based practice, and an increasing use of information technology in health care. Arguments against include the philosophies of holism, the reliance of nurse clinicians on verbal communication, the complexity of nursing data, and cumbersome nature of contemporary information systems. In a healthcare context where the value of nursing must be demonstrated, nurses will need to explore avenues that capitalise on the benefits offered by the establishment of nursing specific data bases, without compromising the preferred standard of nursing care. It is timely that contemporary activities designed to establish common nursing data sets be reviewed. Nursing minimum data sets, unified nursing languages, and more recent approaches including natural language systems, conceptual graphs, multi-axial taxonomies and multi media interfaces, make up an often confusing potpourri of approaches. The intention of this paper is to provide explanations and examples of each approach in an effort to reduce confusion and stimulate further debate.

Databases, Factual↗

PubMed1983

Automatic query formulations in information retrieval.

Modern information retrieval systems are designed to supply relevant information in response to requests received from the user population. In most retrieval environments the search requests consist of keywords, or index terms, interrelated by appropriate Boolean operators. Since it is difficult for untrained users to generate effective Boolean search requests, trained search intermediaries are normally used to translate original statements of user need into useful Boolean search formulations. Methods are introduced in this study which reduce the role of the search intermediaries by making it possible to generate Boolean search formulations completely automatically from natural language statements provided by the system patrons. Frequency considerations are used automatically to generate appropriate term combinations as well as Boolean connectives relating the terms. Methods are covered to produce automatic query formulations both in a standard Boolean logic system, as well as in an extended Boolean system in which the strict interpretation of the connectives is relaxed. Experimental results are supplied to evaluate the effectiveness of the automatic query formulation process, and methods are described for applying the automatic query formulation process in practice.

Computers↗

PubMed2005

Neurotoxic protein oligomers--what you see is not always what you get.

An increasing body of evidence suggests that soluble assemblies of amyloid proteins are the predominant neurotoxic species in many amyloid-related diseases. Consequently, the focus of research on pathologic mechanisms underlying amyloidoses has shifted from amyloid fibrils to oligomers. Biophysical characterization of oligomers is difficult due to their metastable nature. The most popular experimental method for detection of oligomers has been SDS-PAGE. However, we provide experimental evidence that SDS-PAGE is not a reliable method for characterization of amyloid protein oligomers and discuss alternative approaches. In addition, we discuss how inconsistent nomenclature has obfuscated our understanding of the process and products of protein assembly. The goals of this paper are to identify pitfalls associated with the methods and language used to study protein oligomers and to provide alternatives, thereby facilitating successful elucidation of the mechanisms controlling amyloid protein oligomer assembly and toxicity.

Biopolymers↗

PubMed2000

Language impairment in dementia of the Alzheimer type: a hierarchical decline?

OBJECTIVE: Progressive memory impairment is the primary cognitive feature of Alzheimer's disease. Systematic attention to progressive language impairment is under-appreciated. The purpose of this article is to apply the semiotic language framework to organize the disparate findings on language impairment in DAT. METHOD: The semiotic system is hierarchical, going from simple to more complex units of language, with the hierarchical ranks of phonology, morphology, syntax, semantics. This language hierarchy is used as an organizing tool to provide a context for the discrete data on language decline in DAT. Studies relating to language impairment in DAT were identified through an exhaustive computerized search (Medline and Psych Info Database) of available literature spanning the last forty years in which 615 references were examined. Papers were selected for review if reference were made to any one or more of the language parameters of phonology, morphology, syntax, semantics, or to any components or indicators of these parameters, such as sound production, naming, grammar, sentence processing, verbal comprehension in Alzheimer patients. RESULTS: There appears to be an overall relation between language decline and complexity of language both across and within the hierarchical ranks. There also appears to be an associated negative relation between sequence in language development and language decline. Language forms learned last in the sequence of language development are the most complex and appear to be first to deteriorate. CONCLUSIONS: The decline of language in DAT appears to be hierarchical in nature. Further understanding of this hierarchical language decline depends in part on nosologic clarification and subtyping of DAT.

Aging↗

PubMed1993

Answering the connectionist challenge: a symbolic model of learning the past tenses of English verbs.

Supporters of eliminative connectionism have argued for a pattern association-based explanation of language learning and language processing. They deny that explicit rules and symbolic representations play any role in language processing and cognition in general. Their argument is based to a large extent on two artificial neural network (ANN) models that are claimed to be able to learn the past tenses of English verbs (Rumelhart & McClelland, 1986, Parallel distributed processing, Vol. 2, Cambridge, MA: MIT Press; MacWhinney & Leinbach, 1991, Cognition, 40, 121-157). In this article we critically review Rumelhart and McClelland's as well as MacWhinney and Leinbach's ANN models and conclude that they do not succeed in the assigned task of learning the past tenses of English verbs. In order to answer their challenge to the symbolic processing approach, we present our symbolic pattern associator (SPA)-a general-purpose pattern associator that can learn to associate arbitrary discrete patterns. We carried out several experiments with the SPA using the same set of verbs that was used in MacWhinney and Leinbach's simulation with more realistic training and testing procedures. The SPA outperformed the connectionist models by a wide margin in the accuracy of learning, and successful inductive generalizations to unseen verbs. Our SPA has very natural and psychologically realistic explanations to many psychological effects such as U-shaped learning curve, and is much closer to human subjects in predicting past tense of the pseudo-verbs. In contrast to ANNs, whose internal representations are entirely opaque, the SPA can represent the acquired knowledge in the form of production rules that allow for further higher-level processing and integration, resulting in linguistically realistic associative templates for irregular verbs and production rules for regular verbs. In the light of these findings, we conclude that eliminative connectionists' vision of cognition as simple pattern association and pattern recognition without symbolic representation is inadequate. Pattern association as such does not imply rule-less or cue-based models of language acquisition or of human learning in general.

Cognition↗

PubMed1996

Effects of trial complexity on decision making.

The ability of a civil jury to render fair and rational decisions in complex trials has been questioned. However, the nature, dimensions, and effects of trial complexity on decision making have rarely been addressed. In this research, jury-eligible adults saw a videotape of a complex civil trial that varied in information load and complexity of the language of the witnesses. Information load and complexity differentially affected liability and compensatory decisions. An increase in the number of plaintiffs decreased blameworthiness assigned to the defendant despite contrary evidence and amount of probative evidence processed. Complex language did not affect memory but did affect jurors' ability to appropriately compensate differentially worthy plaintiffs. Jurors assigned compensatory awards commensurate with the plaintiffs' injuries only under low-load and less complex language conditions.

Adolescent↗

PubMed1984

A discussion of apraxia, aphasia, and gestural language.

It is understood that damage to the left cerebral hemisphere in adulthood may result in syndromes of language disturbances called the aphasias. The study of these syndromes sheds light on normal language processes, the relationship between language behavior and the brain, and how best to treat aphasic individuals. Aphasia, for some, is a central communication disorder affecting all symbolic behavior in all modalities (i.e., speech, writing, and gesture). Difficulty producing symbolic gestures on command is called apraxia. Others view aphasia as a manifestation of a motor-sequencing disorder affecting all gestural systems including those required for speech movements. These divergent theories of the underlying nature of aphasia can be tested through examination of deaf individuals who use sign language before onset of aphasia. Poizner et al. [Am. J. Physiol. 246 (Regulatory Integrative Comp. Physiol. 15): R868-R883, 1984] studied three such patients with different aphasia syndromes: one patient had a nonsymbolic, motor-sequencing disorder; one had a gestural apraxia; and one had neither. These findings force the conclusion that neither the symbolic nor motor-sequencing theory of aphasia can account for the many varieties of that disorder.

Aphasia↗

PubMedDate not supplied

Categorization in early infancy and the continuity of development.

Arguments and evidence are presented for the conclusion that the young infant's perceptually based categorical representations for natural kinds--animals in this case--are the basis for their mature conceptual counterparts. In addition, it is argued that conceptual development is continuous in nature and without the need for special developmental processes. A consideration of the development of the syllabic, segmental, and featural categories of phonology shows a more complex pattern of change--one marked by both continuities and discontinuities in the representations themselves and the processes that produce them.

Attention↗

PubMedDate not supplied

Dorsal and ventral streams: a framework for understanding aspects of the functional anatomy of language.

Despite intensive work on language-brain relations, and a fairly impressive accumulation of knowledge over the last several decades, there has been little progress in developing large-scale models of the functional anatomy of language that integrate neuropsychological, neuroimaging, and psycholinguistic data. Drawing on relatively recent developments in the cortical organization of vision, and on data from a variety of sources, we propose a new framework for understanding aspects of the functional anatomy of language which moves towards remedying this situation. The framework posits that early cortical stages of speech perception involve auditory fields in the superior temporal gyrus bilaterally (although asymmetrically). This cortical processing system then diverges into two broad processing streams, a ventral stream, which is involved in mapping sound onto meaning, and a dorsal stream, which is involved in mapping sound onto articulatory-based representations. The ventral stream projects ventro-laterally toward inferior posterior temporal cortex (posterior middle temporal gyrus) which serves as an interface between sound-based representations of speech in the superior temporal gyrus (again bilaterally) and widely distributed conceptual representations. The dorsal stream projects dorso-posteriorly involving a region in the posterior Sylvian fissure at the parietal-temporal boundary (area Spt), and ultimately projecting to frontal regions. This network provides a mechanism for the development and maintenance of "parity" between auditory and motor representations of speech. Although the proposed dorsal stream represents a very tight connection between processes involved in speech perception and speech production, it does not appear to be a critical component of the speech perception process under normal (ecologically natural) listening conditions, that is, when speech input is mapped onto a conceptual representation. We also propose some degree of bi-directionality in both the dorsal and ventral pathways. We discuss some recent empirical tests of this framework that utilize a range of methods. We also show how damage to different components of this framework can account for the major symptom clusters of the fluent aphasias, and discuss some recent evidence concerning how sentence-level processing might be integrated into the framework.

Aphasia↗

PubMed1987

Personal reflections on the nature of intelligence in humans and machines.

Computers, the human mind, and social systems have common problems of inadequate memory and insufficient data manipulation speed. In each of these domains, information compression techniques have evolved to reduce storage and processing needs. Among the techniques for information compression, coding of information in procedures stands out as exceptionally powerful. Procedural information coding also gives rise to behavior that may be defined as intelligent. It is found in the human mind, in machines and in social systems. Its use in human thought is aided by language development which promotes regular review of abstract procedures. A practical consequence of better understanding of procedural information coding is the possibility of training people to exhibit greater mental capacity, a controversial possibility. This paper explores the impact of data processing resource limitations, data compression and procedural thinking in men and machines.

Artificial Intelligence↗

PubMed2006

The nature of music from a biological perspective.

Music, as language, is a universal human trait. Throughout human history and across all cultures, people have produced and enjoyed music. Despite its ubiquity, the musical capacity is rarely studied as a biological function. Music is typically viewed as a cultural invention. In this paper, the evidence bearing on the biological perspective of the musical capacity is reviewed. Related issues, such as domain-specificity, innateness, and brain localization, are addressed in an attempt to offer a unified conceptual basis for the study of music processing. This scheme should facilitate the study of the biological foundations of music by bringing together the fields of genetics, developmental and comparative research, neurosciences, and musicology.

Auditory Perception↗

PubMed2006

GiPSi:a framework for open source/open architecture software development for organ-level surgical simulation.

This paper presents the architectural details of an evolving open source/open architecture software framework for developing organ-level surgical simulations. Our goal is to facilitate shared development of reusable models, to accommodate heterogeneous models of computation, and to provide a framework for interfacing multiple heterogeneous models. The framework provides an application programming interface for interfacing dynamic models defined over spatial domains. It is specifically designed to be independent of the specifics of the modeling methods used, and therefore facilitates seamless integration of heterogeneous models and processes. Furthermore, each model has separate geometries for visualization, simulation, and interfacing, allowing the model developer to choose the most natural geometric representation for each case. Input/output interfaces for visualization and haptics for real-time interactive applications have also been provided.

Computer Simulation↗

PubMed2006

Evaluation of the expressiveness of an ICNP-based nursing data dictionary in a computerized nursing record system.

This study evaluated the domain completeness and expressiveness issues of the International Classification for Nursing Practice-based (ICNP) nursing data dictionary (NDD) through its application in an enterprise electronic medical record (EMR) system as a standard vocabulary at a single tertiary hospital in Korea. Data from 2,262 inpatients obtained over a period of 9 weeks (May to July 2003) were extracted from the EMR system for analysis. Among the 530,218 data-input events, 401,190 (75.7%) were entered from the NDD, 20,550 (3.9%) used only free text, and 108,478 (20.4%) used a combination of coded data and free text. A content analysis of the free-text events showed that 80.3% of the expressions could be found in the NDD, whereas 10.9% were context-specific expressions such as direct quotations of patient complaints and responses, and references to the care plan or orders of physicians. A total of 7.8% of the expressions was used for a supplementary purpose such as adding a conjunction or end verb to make an expression appear as natural language. Only 1.0% of the expressions were identified as not being covered by the NDD. This evaluation study demonstrates that the ICNP-based NDD has sufficient power to cover most of the expressions used in a clinical nursing setting.

Dictionaries as Topic↗

PubMed2003

Pseudo-reorganization of language cortical function at fMR imaging: a consequence of tumor-induced neurovascular uncoupling.

A left-handed patient with a grade II left frontal lobe astrocytoma had spontaneous seizures causing speech arrest and uncontrolled right upper extremity movements. Word-generation functional MR (fMR) imaging showed activity nearly exclusively in the right inferior frontal gyrus. The clinical history of the speech arrest and the intraoperative mapping proved left-hemisphere language dominance. Tumor involvement of the left inferior frontal gyrus caused uncoupling of the blood oxygenation level-dependent (BOLD) and neuronal response, leading to the erroneous fMR imaging appearance of right-hemisphere language dominance. Discrepancies between BOLD and intraoperative mapping in areas near lesions illustrate the complementary nature of these techniques.

Adult↗

PubMed1994

[Not Available].

The language of alchemy may be divided into five layers. - Within the first layer the alchemists explicitly and undisguisedly conveyed chemical informations. But they described chemical substances and chemical operations in a way which reminds us of sociological or psychological descriptions and the treatment of complex personalities. - Within the second layer the alchemists also gave chemical informations albeit encoded in much the same way as craftmen's guilds encoded their knowledge to fend off competition from outsiders. - Within the third layer the alchemists refer to verbal associations and to myths from their cultural environment so that their texts can only be properly understood within a certain cultural context. As the language of this layer was often handed down to later generations of alchemists who were not acquainted with the specific cultural context it tended to cause confusions and misunderstandings. - Within the fourth layer the alchemists deliberately used an arcane language for within this layer they tried to convey the paradoxa of alchemy. - Within the fifth ayer alchemy is treated as a literary tradition in which all classical texts contain the truth but no text does it in a fully comprehensible way. - These last two layers show that au fond alchemy is not a process of riddle solving but a quest for cosmic secrets. This gives us a demarcation criterion to distinguish alchemy from genuine natural sciences.

Alchemy↗

PubMed1999

Sources of flexibility in human cognition: dual-task studies of space and language.

Under many circumstances, children and adult rats reorient themselves through a process which operates only on information about the shape of the environment (e.g., Cheng, 1986; Hermer & Spelke, 1996). In contrast, human adults relocate themselves more flexibly, by conjoining geometric and nongeometric information to specify their position (Hermer & Spelke, 1994). The present experiments used a dual-task method to investigate the processes that underlie the flexible conjunction of information. In Experiment 1, subjects reoriented themselves flexibly when they performed no secondary task, but they reoriented themselves like children and adult rats when they engaged in verbal shadowing of continuous speech. In Experiment 2, subjects who engaged in nonverbal shadowing of a continuous rhythm reoriented like nonshadowing subjects, suggesting that the interference effect in Experiment 1 did not stem from general limits on working memory or attention but from processes more specific to language. In further experiments, verbally shadowing subjects detected and remembered both nongeometric information (Experiment 3) and geometric information (Experiments 1, 2, and 4), but they failed to conjoin the two types of information to specify the positions of objects (Experiment 4). Together, the experiments suggest that humans' flexible spatial memory depends on the ability to combine diverse information sources rapidly into unitary representations and that this ability, in turn, depends on natural language.

Adolescent↗