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PubMed1987

Managing research data with self-documenting files.

Processing biomedical research data is frequently complex due to the evolutionary nature of experiments and the requisite modification of analysis software. For the past several years we have been evolving a set of software tools designed to improve our ability to respond to evolving experimental designs. These tools allow the investigator to easily manipulate the research data and specify desired data transformations at run time. Coupling of analysis software to research data files is dependent on data files that are commented in a manner similar to that used in programming languages. The resulting annotated data files are self-documenting, and their use facilitates visual interpretation of displayed data as well as automatic processing of subsets of data. Here we present a formal description of a self-documenting file and describe several software tools that facilitate processing of biomedical research data.

Electronic Data Processing↗

PubMed2006

fMRI correlates of cortical specialization and generalization for letter processing.

The present study used functional magnetic resonance imaging to examine cortical specialization for letter processing. We assessed whether brain regions that were involved in letter processing exhibited domain-specific and/or mandatory responses, following Fodor's definition of properties of modular systems (Fodor, J.A., 1983. The Modularity of Mind. The MIT Press, Cambridge, MA.). Domain-specificity was operationalized as selective, or exclusive, activation for letters relative to object and visual noise processing and a baseline fixation task. Mandatory processing was operationalized as selective activation for letters during both a silent naming and a perceptual matching task. In addition to these operational definitions, other operational definitions of selectivity for letter processing discussed by [Pernet, C., Celsis, P., Demonet, J., 2005. Selective response to letter categorization within the left fusiform gyrus. NeuroImage 28, 738-744] were applied to the data. Although the left fusiform gyrus showed a specialized response to letters using the definition of selectivity put forth by [Pernet, C., Celsis, P., Demonet, J., 2005. Selective response to letter categorization within the left fusiform gyrus. NeuroImage 28, 738-744], this region did not exhibit specialization for letters according to our more conservative definition of selectivity. Instead, this region showed equivalent activation by letters and objects in both the naming and matching tasks. Hence, the left fusiform gyrus does not exhibit domain-specific or mandatory processing but may reflect a shared input system for both stimulus types. The left insula and some portions of the left inferior parietal lobule, however, did show a domain-specific response for letter naming but not for letter matching. These regions likely subserve some linguistically oriented cognitive process that is unique to letters, such as grapheme-to-phoneme translation or retrieval of phonological codes for letter names. Hence, cortical specialization for letters emerged in the naming task in some peri-sylvian language related cortices, but not in occipito-temporal cortex. Given that the domain-specific response for letters in left peri-sylvian regions was only present in the naming task, these regions do not process letters in a mandatory fashion, but are instead modulated by the linguistic nature of the task.

Adult↗

PubMed2006

Adding up the effects of cultural experience on the brain.

How does the brain represent number and perform mathematical calculations? According to a recent and provocative study by Tang and colleagues, it depends on which language you learn. They found that the divergent linguistic and cultural experiences of native Chinese and native English speakers are associated with distinct patterns of brain activity during mathematical processing. Their results raise important questions about the cognitive and neural specificity of cultural influences on mathematical processes and the core nature of mathematical cognition.

Brain↗

PubMedDate not supplied

A true posterior tibial artery aneurysm--a case report.

Aneurysms of infrapopliteal arteries are rare. The etiology is usually traumatic, and most aneurysms are false. The English-language literature reports only 33 cases of infrapopliteal arterial true aneurysms, of which 8 involve the posterior tibial artery. The etiology of these lesions is unclear; a fibromuscular fibrodysplasia similar to ulnar aneurysm may be hypothesized, but traumatic, atherosclerotic, inflammatory, and other pathological processes are also probably involved. The natural history seems to be related to thrombosis and distal embolism more than to rupture. Surgical indications are debated. Aneurysm repair with a complete restoration of the blood flow through the affected artery is particularly challenging owing to the small size of the vessels, and ligation may be required. We report, to the best of our knowledge, the first case of an atherosclerotic posterior tibial artery true aneurysm successfully treated with aneurysmectomy and end-to-end direct reconstruction with a documented good long-term patency. Clinical features, imaging findings, and surgical management are described; indications and treatments (open or endovascular) are discussed.

Anastomosis, Surgical↗

PubMedDate not supplied

The geography of thinking.

People in different cultures are taught to think differently. How we gather information, process, rationalise, justify and communicate our ideas is culturally determined. Europe is divided between the pragmatic, inductive thinking of North Sea cultures and the rationalist thinking of the rest of the continent. Westerners and Asians have different mental skills and capacities deriving from the nature of written and spoken language, the relative importance of learning by rote or investigation and the social environment. Western children are expected to ask questions and test ideas for themselves, while in Asia it is unacceptable to question anyone senior in age or authority, including teachers. Westerners base thinking on reason; Asians base thinking on harmony. Whenever people of different cultures work together, different ways of thinking create barriers to understanding and communication. This applies to many spheres of work, including the medical profession.

Asia↗

PubMed1995

Integration architecture: the ISAR project.

ISAR (Integration System Architecture) will integrate six AIM Projects on the HIS platform at the University Hospital (CHRU) of LILLE. These Projects were elicited from six European consortiums that provided prototypes or pre-competitive products. These consortia are: ESTEEM (storage and analysis of electromyograms), EURIPACS (picture archiving and communication system), MENELAS (analysis of the natural language for medical applications), OEDIPE (storage and serial analysis of electrocardiograms), OPADE (help with drug prescription), and TANIT (mobile system for anaesthesia). When introducing an information system to a medical department and running it, two issues arise. First, how can the Information system be anchored to the Clinical processes in order to support them in an effective and efficient way, and, second, how can the Information system adapt to the changes in the Clinical processes?

Computer Communication Networks↗

PubMed1991

Interictal cognitive changes in epilepsy.

There is little evidence for significant intellectual deterioration in well-controlled seizure disorders. With recurrent convulsive seizures, the picture is less clear and depends on severity, type, age of onset, and frequency of toxic levels of antiepileptic drugs (see Table 1). In the interictal state, deficits in verbal language and memory have been observed, especially in patients with complex partial seizure foci in the left (dominant) hemisphere. The memory deficits appear to affect new learning and retention of material; the verbal deficits are more subtle, affecting word-finding, verbal fluency, and comprehension abilities. Both of these changes may either go unnoticed by the patient in day to day activities or be attributed to the effects of antiepileptic medication. Antiepileptic drugs can also affect interictal cognitive functioning. The worst of these appears to be phenobarbital; phenytoin has an intermediate effect; valproic acid and carbamazepine as single agents seem to produce fewer adverse effects. However, individual patients may be particularly sensitive to cognitive side effects of certain drugs. Finally, attention deficits and slowing of cognitive processes, either chronically or intermittently, appear to affect all seizure patients to some extent. The syndrome is more prominent in frontal or generalized seizure patterns. The intermittent nature of these disturbances has been emphasized in recent research on subclinical interictal spike-wave electrical phenomena.

Anticonvulsants↗

PubMed1992

From concepts to lexical items.

In this paper we address the question how in language production conceptual structures are mapped onto lexical items. First we describe the lexical system in a fairly abstract way. Such a system consists of, among other things, a fixed set of basic lexical entries characterized by four groups of information: phonetic form, grammatical features, argument structure, and semantic form. A crucial assumption of the paper is that the meaning in a lexical entry has a complex internal structure composed of more primitive elements (decomposition). Some aspects of argument structure and semantic form and their interaction are discussed with respect to the issue of synonymy. We propose two different mappings involved in lexical access. One maps conceptual structures to semantic forms, and the other maps semantic forms to conceptual structures. Both mappings are context dependent and are many-to-many mappings. We present an elaboration of Levelt's (1989) model in which these processes interact with the grammatical encoder and the mental lexicon. Then we address the consequences of decomposition for processing models, especially the nature of the input of lexical access and the time course. Processing models that use the activation metaphor may have difficulties accounting for certain phenomena where a certain lemma triggers not one, but two or more word forms that have to be produced with other word forms in between.

Female↗

PubMed2005

Revisiting the role of Broca's area in sentence processing: syntactic integration versus syntactic working memory.

Most previous neuroimaging studies of sentence processing have associated Broca's area with syntactic processing; however, the exact nature of the processes subserved by this brain region is yet not well understood. Although some authors suggest that Brodmann area (BA) 44 of the left inferior frontal gyrus (i.e., Broca's area) is relevant for syntactic integration processes, others claim that it is associated with working memory mechanisms relevant for language processing. To dissociate these two possible functions, the present study investigated hemodynamic responses elicited while participants processed German indirect wh-questions. Activation increases were observed in left BA 44 together with superior temporal areas and right hemispheric homologues for sentences with noncanonical word order, in which a verb argument was dislocated from its canonical position over a relatively long distance. In these sentences, syntactic working memory load was assumed to be greatest. In contrast, no activation increase was elicited by object-initial as opposed to subject-initial sentences that did not differ with respect to working memory costs but with respect to syntactic integration costs. These data strongly suggest that Broca's area plays a critical role in syntactic working memory during online sentence comprehension.

Adult↗

PubMed1996

Disconnected phonology: a linguistic analysis of phonemic jargon aphasia.

This paper reports on indications of the nature of the neurolinguistic connection between phonological and lexical components of language, based on a case of phonemic jargon aphasia. Following bihemispheric embolic infarcts, the subject presented with severe fluent aphasia, characterized by fluent strings of phonemes, with virtually no intelligible utterances. Despite nearly total jargonized output, the fundamental phonological processes of speech were largely intact. Specifically she demonstrated: (1) English phonotactics and English stress-timed rhythmic principles, (2) aspirated stops word-initially and glottalized stops word-finally, (3) utterance final declination of pitch, and (4) stressed syllable vowel lengthening. Additionally, regional-specific (Southern American English) phonological processes, including monophthongization, in-gliding, and front vowel backing, were also preserved. Overall, the investigation reveals an example of an intact phonological rule system operating on a grossly disturbed input (lexical representation).

Aphasia, Wernicke↗

PubMed1999

Reading skills in hyperlexia: a developmental perspective.

Hyperlexia is characterized by advanced word-recognition skills in individuals who otherwise have pronounced cognitive, social, and linguistic handicaps. Language, word recognition, and reading-comprehension skills are reviewed to clarify the nature and core deficits associated with the disorder. It is concluded that hyperlexia should be viewed as part of the normal variation in reading skills, which are themselves associated with individual differences in phonological, orthographic, and semantic processing, short-term memory, and print exposure. A compulsive preoccupation with reading may also be crucial to the development of a hyperlexic reading profile. A theoretical framework, based on recent connectionist models of reading development, is described. This perspective provides a satisfactory account for how individual differences in a number of different skills can lead to a variety of manifestations of reading behavior, including hyperlexia.

Child↗

PubMed1999

The evolution of language.

The emergence of language was a defining moment in the evolution of modern humans. It was an innovation that changed radically the character of human society. Here, we provide an approach to language evolution based on evolutionary game theory. We explore the ways in which protolanguages can evolve in a nonlinguistic society and how specific signals can become associated with specific objects. We assume that early in the evolution of language, errors in signaling and perception would be common. We model the probability of misunderstanding a signal and show that this limits the number of objects that can be described by a protolanguage. This "error limit" is not overcome by employing more sounds but by combining a small set of more easily distinguishable sounds into words. The process of "word formation" enables a language to encode an essentially unlimited number of objects. Next, we analyze how words can be combined into sentences and specify the conditions for the evolution of very simple grammatical rules. We argue that grammar originated as a simplified rule system that evolved by natural selection to reduce mistakes in communication. Our theory provides a systematic approach for thinking about the origin and evolution of human language.

Biological Evolution↗

PubMed1977

Changes in primary process expression in hospitalized schizophrenics treated with phenothiazines: two projective tasks compared.

It was hypothesized that primary process expression on Gottschalk's Five Minute Verbalization Task (FMV) would be more representative of clinical status in schizophrenia than primary process expression on the Rorschach. Ss were 21 males and 15 females, ages 19-41 years, newly admitted to the hospital and treated with phenothiazines. The FMV was administered at predrug, five weeks, and 13 weeks, and the Rorschach at predrug and five weeks. Primary process scoring was according to the Holt system. Clinical improvement was measured by the Lorr IMPS and the Burdock Ward Behavior Scale. Over time, Ss produced less primary process on the FMV (p less than .001), while on the Rorschach scores did not change significantly. The scores on the FMV but not on the Rorschach paralleled some measures of clinical improvement (p less than .05). In a factor analysis, scores on the FMV and Rorschach were related to specific but different symptoms. It was concluded that the FMV was more effective in determining clinical improvement, while the Rorschach was perhaps more valuable in assessing the nature of the primary process thinking.

Adult↗

PubMed2003

Ethics of research involving humans: uniform processes for disparate categories?

The Australian Health Ethics Committee's National Statement on Ethical Conduct in Research Involving Humans (1999) expanded the health and medical focus of preceding statements by including all disciplines of research. The Statement purports to promote a uniformly high ethical standard for this expanded range of research, and is endorsed by, inter alia, the Australian Academy of the Humanities, the Australian Academy of Science, and the Academy of Social Sciences in Australia. High ethical standards should apply to all research involving humans. However, uniformity in the review processes of disparate research endeavors is not a necessary condition for uniformly high ethical standards. Bringing the ethical review of all research under a model which has developed within the context of health and medical research ethics for over thirty years may be inappropriate and at times incoherent. The language, methods, nature and products of research in areas such as the Humanities are often very different from those of health, medical and other sciences. The Behavioral and Social Sciences Ethics Review Committee at The University of Queensland (UQ) had, since the mid-1980s, considered that the guidelines of the time did, in fact, cover all aspects of human experimentation. We describe the ways in which this position was implemented, how issues raised by the new wording in the National Statement have been recently managed by UQ's research ethics committees, and point to outstanding questions.

Advisory Committees↗

PubMed1991

Acalculia: an historical review of localization.

This article reviews the brain localization of calculation disorders (acalculia) beginning with Gall's claim in the early 19th century for a "center" of calculation. A renewed interest in the subject arose around the time of Henschen during the first quarter of the 20th century. A summary of the cases of acalculia since Henschen leads to the conclusion that regardless of the functional modular nature of calculation ability, there is neither a localized region nor a specific hemisphere uniquely underlying the disorder.

Brain↗

PubMed2000

The design and development of an integrated natural products screening database.

We designed and developed NEXUS--a new natural products screening database and related suite of software applications--to utilize the spectacular increases in assay capacity of the modern high throughput screening (HTS) environment. NEXUS not only supports seamless integration with separate HTS systems, but supports user-customized integration with external laboratory automation, particularly sample preparation systems. Designed and developed based on a detailed process model for natural products drug discovery, NEXUS comprises two integrated parts: (1) a single schema of Oracle tables and callable procedures and functions, and (2) software "front-ends" to the database developed using Microsoft Excel and Oracle Discovery/2000. Many of the back-end processing functions were written in Programming Language/Structured Query Language (PL/SQL) to provide an Application Programmer's Interface, which allows end users to create custom applications with little input from information technology professionals.

Biological Products↗

PubMed1991

Poststroke depression: neurologic, physiologic, diagnostic, and treatment implications.

Poststroke depression is a serious disorder that can compromise the overall rehabilitative process, including speech-language treatment. To provide patients with the maximum opportunity for recovery and therapeutic gains, speech-language pathologists need to increase their awareness of depression and understand the neurologic, physiologic, diagnostic, and treatment implications of this disorder. This article defines depression and reviews the theories that explain the nature of the disorder as well as methods for diagnosing and treating stroke patients who are clinically depressed.

Cerebrovascular Disorders↗

PubMed2004

Integration of letters and speech sounds in the human brain.

Most people acquire literacy skills with remarkable ease, even though the human brain is not evolutionarily adapted to this relatively new cultural phenomenon. Associations between letters and speech sounds form the basis of reading in alphabetic scripts. We investigated the functional neuroanatomy of the integration of letters and speech sounds using functional magnetic resonance imaging (fMRI). Letters and speech sounds were presented unimodally and bimodally in congruent or incongruent combinations. Analysis of single-subject data and group data aligned on the basis of individual cortical anatomy revealed that letters and speech sounds are integrated in heteromodal superior temporal cortex. Interestingly, responses to speech sounds in a modality-specific region of the early auditory cortex were modified by simultaneously presented letters. These results suggest that efficient processing of culturally defined associations between letters and speech sounds relies on neural mechanisms similar to those naturally evolved for integrating audiovisual speech.

Adult↗