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PubMed1994

Using cross-modal lexical decision tasks to investigate sentence processing.

Recent investigations of sentence processing have used the cross-modal lexical decision task to show that the antecedent of a phonologically empty noun phrase (specifically, WH-trace) is reactivated at the trace position. G. McKoon, R. Ratcliff, and G. Ward (1994) claimed that (a) a design feature concerning the choice of related and unrelated targets is a possible confound in this work and (b) the conclusions drawn from this previous research are therefore called into question. These claims are considered in light of both McKoon et al.'s experimental findings and results of our own experiments in which we test their linguistic materials. We argue that their results may be due to the nature of their materials. Additionally, we argue that a follow-up experiment reported by G. McKoon and R. Ratcliff (1994) used a technique that is not comparable to the cross-modal lexical decision task. It is concluded that current evidence supports the claim that structural information is using during on-line sentence processing and that the cross-modal technique is sensitive to this.

Cognition↗

PubMed1997

Genetic factors in reproduction and their evolutionary significance.

PROBLEM: The reproductive process is a major driving force in human evolution. An evolutionary perspective was brought to bear on some aspects of reproduction and its aberrations, and, conversely, some of the insights of modern reproductive genetics were used to investigate problems in evolution. METHOD: The data used were obtained from the literature in evolution, anthropology, archeology, linguistics, and genetics. RESULTS: The evolutionary line leading to modern humans diverged from that leading to the chimpanzees approximately 5-7 million years ago (Mya). Archaic Homo sapiens emerged ca. 0.3 Mya, and modern Homo sapiens and the development of language ca. 0.1 Mya; thus, modern humans occupy approximately 2% of the evolutionary history of the hominid line. During all of this time, the ancestors of modern humans were migratory hunter-gatherers. It was only during the Neolithic transition ca. 0.01 Mya (approximately 0.2% of hominid evolutionary history) that agriculture was developed, and with it a settled lifestyle that allowed a more stable existence and the development of a different reproductive pattern. Various estimates indicate that the human population increased from 0.05 million at the time of the emergence of modern Homo sapiens to 6,000 million at the present time (120,000-fold increase). CONCLUSIONS: These evolutionary considerations were used to explore three areas: (1) the extinction of the Neanderthals, who coexisted for ca. 65,000 years with modern humans; (2) the relatively low and stable rate of human conceptions (20-35% of ova fertilized naturally or fertilized in vitro); and (3) the long postnatal period required for the full maturation of the immune response. From these considerations, a broad view of the human reproductive process was obtained that may provide some insight into the rationale for the development of effective reproductive technologies.

Animals↗

PubMed2003

The recognition of gender-marked nouns and verbs in Polish-speaking aphasic patients.

In the present study, we investigated the on-line recognition of gender-marked lexical items by three aphasic patients and eighteen matched control participants, all native speakers of Polish. Polish is unique in that it allows investigating grammatical gender across the major categories of nouns and verbs. Patients and their controls were tested using a simple visual lexical decision paradigm in which gender, number and grammatical category were manipulated. Results show that, while response latencies were markedly slower for aphasic patients, gender did not yield differential results in either grammatical category, for both patients and control participants. Plural forms, on the other hand, showed significantly slower response latencies than singular forms in both brain-damaged and unimpaired participants, but only for nouns. We interpret these findings in terms of the inherent vs. contextual, i.e. underspecified, nature of gender and number in the two grammatical categories. This study suggests that while gender can be impaired in off-line performance in aphasia, on-line recognition patterns parallel the performance of non-brain-damaged individuals, confirming the preservation of access procedures in automatic word recognition.

Aged↗

PubMed2000

Principles that are invoked in the acquisition of words, but not facts.

A controversial question is whether language acquisition is the result of domain-general or domain-specific principles. Focusing on word-learning, Markson and Bloom (Nature 385(6619) (1997) 813) recently argued that the ability to learn and retain new words (count nouns) is the result of abilities that are not specific to language. In the current experiment, we replicate their empirical finding, but challenge their domain-general interpretation by highlighting a crucial distinction between the principles involved in learning a count noun, as compared to learning a fact. The current results confirm that learning count nouns and facts involve (at least) two common components: establishing a mapping to a designated individual, and retaining this mapping over time. However, these results go further to document that the processes invoked in the acquisition of words differ from those invoked in the acquisition of facts. Children spontaneously and systematically extended a novel count noun exclusively to other members of the same category, but revealed no such systematicity when extending a fact. This illustrates that there are principles that are invoked in learning a novel count noun that are not invoked in learning a fact.

Analysis of Variance↗

PubMed1997

Interleukin-10: biology, role in inflammation and autoimmunity.

LEARNING OBJECTIVES: Reading this article will increase the readers' knowledge of the biology of interleukin-10 (IL-10) an important cytokine. The survival of an organism and its host defense mechanisms require, among other processes, a complex but target-oriented interaction and an interdependence between the immune and inflammatory pathways. The biologic role of interleukin-10 in these processes is presented as well as the possible involvement of IL-10 in the pathogenesis of various diseases. The influence of pharmacologic agents on IL-10 production and the possible pharmacologic role of IL-10 itself are discussed. DATA SOURCES: A detailed literature search was conducted. Studies considered relevant and important involving both humans and animals, in all languages were used. STUDY SELECTION: Material was taken only from peer reviewed journals. RESULTS: IL-10 is produced by CD4+, Tho, Th1, B lymphocytes, mast cells, eosinophils, monocytes, macrophages and keratinocytes. IL-10 has a diverse array of actions, which differ depending on cell type, nature of stimulus and the cellular microenvironment. Interleukin-10 has an important role in the inflammatory and immune systems. In addition, present studies suggest that IL-10 may well play a pivotal role in the pathogenesis of several diseases. It has the potential for therapeutic use. Most of the data on IL-10 have been obtained from in vitro studies or animal experiments. Studies on humans are few, but rapidly increasing. CONCLUSIONS: Interleukin-10 is an important molecule with a central role in maintaining health and in the pathogenesis of disease. Known pharmacologic agents and some under investigation can modify IL-10 production in vivo. Development of agents that can selectively affect a very specific biologic action of IL-10 may provide significant benefit in treating autoimmune and inflammatory diseases.

Animals↗

PubMed1999

Effects of rate of presentation on the reception of American Sign Language.

Previous research on the visual reception of fingerspelled English suggests that communication rates are limited primarily by constraints on production. Studies of artificially accelerated fingerspelling indicate that reception of fingerspelled sentences is highly accurate for rates up to 2 to 3 times those that can be produced naturally. The current paper reports on the results of a comparable study of the reception of American Sign Language (ASL). Fourteen native deaf ASL signers participated in an experiment in which videotaped productions of isolated ASL signs or ASL sentences were presented at normal playback speed and at speeds of 2, 3, 4, and 6 times normal speed. For isolated signs, identification scores decreased from 95% correct to 46% correct across the range of rates that were tested; for sentences, the ability to identify key signs decreased from 88% to 19% over the range of rates tested. The results indicate a breakdown in processing at around 2.5-3 times the normal rate as evidenced both by a substantial drop in intelligibility in this region and by a shift in error patterns away from semantic and toward formational. These results parallel those obtained in previous studies of the intelligibility of the auditory reception of time-compressed speech and the visual reception of accelerated fingerspelling. Taken together, these results suggest a modality-independent upper limit to language processing.

Adult↗

PubMed2003

Visual categorization: accessing abstraction in non-human primates.

Evolution might have set the basic foundations for abstract mental representation long ago. Because of language, mental abilities would have reached different degrees of sophistication in mammals and in humans but would be, essentially, of the same nature. Thus, humans and animals might rely on the same basic mechanisms that could be masked in humans by the use of sophisticated strategies. In this paper, monkey and human abilities are compared in a variety of perceptual tasks including visual categorization to assess behavioural similarities and dissimilarities, and to determine the level of abstraction of monkeys' mental representations. The question of how these abstract representations might be encoded in the brain is then addressed. A comparative study of the neural processing underlying abstract cognitive operations in animals and humans might help to understand when abstraction emerged in the phylogenetic scale, and how it increased in complexity.

Animals↗

PubMed2001

[Biological child and adolescent psychiatry and social psychiatry: controversies and comments].

There is an ongoing debate in the child and adolescent psychiatry on the question of 'nature or nurture', as it was pointed out many years ago by Michael Rutter (1986). Newer studies anchored in both areas support hypotheses of mutual interferences and give biological explanations for social behavior. To date, it is no question anymore, whether biological child and adolescent psychiatry and social psychiatry are contradictory or in line. They are in a steady process, look at the same development, the same symptom from different points of view. They describe it with concepts, which are not understood from the other position, because of different contexts and possible because of ideologic influences. The goal must be to find a common language--especially with respect to the patient.

Adolescent↗

PubMed2004

Monkey homologues of language areas: computing the ambiguities.

The 'language-readiness' of human brains most probably resulted from modification of structures present in non-human primate brains, but identifying such homologues and the nature of their modifications has been highly problematic. In a recent article, Arbiband Bota suggest that these problems can be overcome using a neuroinformatics approach. But its assumptions ignore many non-local, activity-dependent, regressive, and allometric effects of neurodevelopment that violate assumptions of classic homology. What if these effects are what matter most?

Animals↗

PubMed1991

Generation of color composites for enhanced tissue differentiation in magnetic resonance imaging of the brain.

Currently, the diagnostic interpretation of magnetic resonance (MR) images requires that radiologists integrate specific tissue contrast information from several different images obtained at the same anatomic slice position. Each of these images has its own unique tissue contrast patterns which are based on the image acquisition parameters (pulse sequence) selected. The complex contrast patterns observable in these images reflect the inherent biophysical characteristics of the tissues and fluids present in the imaged section. In an effort to increase the diagnostic accuracy and efficiency of MR image interpretation, we have generated color composite images from quantitatively analyzed achromatic MR images of the brain, obtained while utilizing different pulse sequences. By using a DEC MicroVAX II computer with Interactive Digital Language (IDL), this color display method has been applied to images obtained from General Electric Signa and Siemens Magnatom imagers. For this study, our image sets included T1-weighted, T2-weighted, and proton density spin echo sequences as well as both high and low flip angle gradient echo sequences. Advantages of our color composite methods, in contrast to many other image processing techniques that have been described, are that minimal information is lost, computer misclassification of tissues is avoided, and the conspicuity of specific tissues is enhanced. Furthermore, with this method it is possible to produce composite images whose color renditions approach a natural anatomic tissue appearance. Availability of these color composites to radiologists may improve the efficiency and accuracy of the diagnostic interpretation of MR images.

Brain↗

PubMed2003

False belief understanding in maltreated children.

False belief understanding was investigated in maltreated (N = 203), low socioeconomic status (SES) nonmaltreated (N = 143), and middle SES nonmaltreated (N = 172) 3- to 8-year-old children. Contrasts among the three groups provided an opportunity to examine the impact of family contextual influences on theory of mind development. Specifically, child maltreatment served as an "experiment of nature" in order to elucidate theory of mind abilities. Two false belief tasks and language assessments were administered. Among children with a verbal mental age of 49 months or greater, maltreatment was related to delays in the development of theory of mind, beyond the influence of chronological age and SES. The occurrence of maltreatment during the toddler period, onset during the toddler years, and physical abuse were features of maltreatment associated with delay in the development of theory of mind. Findings are discussed in terms of the influence of harsh caregiving on the development of theory of mind. Implications for the understanding of normal developmental processes are highlighted.

Child↗

PubMed1998

Concept-oriented standardization and statistics-oriented classification: continuing the classification versus nomenclature controversy.

Nowadays, most activities on controlled medical vocabularies focus on the provision of a sufficient atomic-level granularity for representing clinical data. Amongst others, clinical vocabularies should be concept oriented, compositional and should also reject "Not Elsewhere Classified". We strongly share the opinion that there is a need to deal with serious deficits of existing manually created vocabularies and with new demands for computer-based advanced processing and exchange of medical language data. However, we do not share the opinion that methodological requirements like observational and structural comparability needed for sound statistics should not be included in desiderata of controlled medical vocabularies. Statistical-oriented classifications are not developed for representing detailed clinical data but for providing purpose-dependent classes where cases of interest are assigned uniquely. Either statistical classifications are not included into the set of controlled medical vocabularies in the sense of Cimino, or his desiderata are misleading. We argue that statistical classifications should be linked to (formal) concept systems, but again this linkage does not change their different natures. With this article we continue the "classification versus nomenclature" controversy referring to Coté.

Data Interpretation, Statistical↗

PubMed2006

Similarity-based interference during language comprehension: Evidence from eye tracking during reading.

The nature of working memory operation during complex sentence comprehension was studied by means of eye-tracking methodology. Readers had difficulty when the syntax of a sentence required them to hold 2 similar noun phrases (NPs) in working memory before syntactically and semantically integrating either of the NPs with a verb. In sentence structures that placed these NPs at the same linear distances from one another but allowed integration with a verb for 1 of the NPs, the comprehension difficulty was not seen. These results are interpreted as indicating that similarity-based interference occurs online during the comprehension of complex sentences and that the degree of memory accessibility conventionally associated with different types of NPs does not have a strong effect on sentence processing.

Attention↗

PubMed2003

Building bridges between body and mind: The analysis of an adolescent with paralyzing chronic pain.

This paper describes the evaluation, initial psychotherapy and subsequent psychoanalysis of an adolescent who presented with a severe psychosomatic process involving total body pain and profound fatigue. The author details the complex and multifaceted nature of the psychosomatic process as it unfolded in the treatment. The psychosomatic problem was not a single entity, but rather was comprised of diverse interwoven elements such as somatization, conversion on pre-oedipal and oedipal levels, conflicts over aggression, sexuality, identity, masochism, secondary gain, anaclitic depression, internalized self-other interactions with a depressed mother and transgenerational transmission of trauma. The author uses the case material to discuss technical approaches to problems that often arise in the analytic treatment of patients with complicated chronic pain and fatigue as the primary complaints. Such approaches include respecting the mind-body split as a primary defense, speaking the language of the body along with the language of the mind and developing the verbal sphere around the non-verbal symptoms. The author emphasizes that complicated chronic pain problems are common and can be helped by psychoanalysis as long as the unique and complex features are understood and reflected in the technical approach.

Adolescent↗

PubMedDate not supplied

Financial impact of health promotion programs: a comprehensive review of the literature.

PURPOSE: The purpose of this review is to summarize the literature on the ability of health promotion programs to reduce employee-related health care expenditures and absenteeism. SEARCH PROCESS: Using key words in a literature-searching program, a comprehensive search was conducted on the following databases: MEDLINE, Embase, HealthSTAR. SPORTDiscus, PsycINFO, SciSearch, ERIC, and ABI Inform. STUDY INCLUSION AND EXCLUSION CRITERIA: All data-based studies that appeared in peer reviewed journals in the English language. Theses, dissertations, or presentation abstracts that were not published in peer reviewed journals were excluded. The initial search identified 196 studies, but only 72 met the inclusion criteria and were included in the review. DATA EXTRACTION METHODS: Summary tables were created that include design classification, subject size, results, and other key information for each study. DATA SYNTHESIS: Both the nature of the findings and the overall quality of the literature were evaluated in an attempt to answer two questions: Do individuals or populations with high health risks have worse financial outcomes than individuals or populations with low health risks? Do health promotion programs improve financial outcomes? MAJOR CONCLUSIONS: There are good correlational data to suggest that high levels of stress, excessive body weight, and multiple risk factors are associated with increased health care costs and illness-related absenteeism. The associations between seat belt use, cholesterol, diet, hypertension, and alcohol abuse and absenteeism and health care expenditures are either mixed or unknown. Health promotion programs are associated with lower levels of absenteeism and health care costs, and fitness programs are associated with reduced health care costs.

Absenteeism↗

PubMed2005

Reference assignment: using language breakdown to choose between theoretical approaches.

We report results of an experimental study with Dutch agrammatic aphasics that investigated their ability to interpret pronominal elements in transitive clauses and Exceptional Case Marking constructions (ECM). Using the obtained experimental results as a tool, we distinguish between three competing linguistic theories that aim at determining principles responsible for pronoun distribution: Government and Binding (Chomsky, 1981), Reflexivity (Reinhart & Reuland, 1993), and Primitives of Binding (Reuland, 2001). The obtained results are inconsistent with Government and Binding, but consistent with the latter two theories. We further show that the Primitives of Binding framework most naturally explains our results. Our proposal is based on the different performance demonstrated by patients in transitive clauses and ECM constructions, in combination with the often-made claim in the literature regarding the limitation of processing resources in this population (e.g., Haarmann and Kolk, 1991, Haarmann and Kolk, 1994 and Zurif et al., 1993, among others).

Adult↗

PubMed2006

[Modeling developmental aspects of sensorimotor control of speech production].

BACKGROUND: Detailed knowledge of the neurophysiology of speech acquisition is important for understanding the developmental aspects of speech perception and production and for understanding developmental disorders of speech perception and production. METHOD: A computer implemented neural model of sensorimotor control of speech production was developed. The model is capable of demonstrating the neural functions of different cortical areas during speech production in detail. RESULTS: (i) Two sensory and two motor maps or neural representations and the appertaining neural mappings or projections establish the sensorimotor feedback control system. These maps and mappings are already formed and trained during the prelinguistic phase of speech acquisition. (ii) The feedforward sensorimotor control system comprises the lexical map (representations of sounds, syllables, and words of the first language) and the mappings from lexical to sensory and to motor maps. The training of the appertaining mappings form the linguistic phase of speech acquisition. (iii) Three prelinguistic learning phases--i. e. silent mouthing, quasi stationary vocalic articulation, and realisation of articulatory protogestures--can be defined on the basis of our simulation studies using the computational neural model. These learning phases can be associated with temporal phases of prelinguistic speech acquisition obtained from natural data. CONCLUSIONS: The neural model illuminates the detailed function of specific cortical areas during speech production. In particular it can be shown that developmental disorders of speech production may result from a delayed or incorrect process within one of the prelinguistic learning phases defined by the neural model.

Brain Mapping↗

PubMed2006

Describing the impact of health research: a Research Impact Framework.

BACKGROUND: Researchers are increasingly required to describe the impact of their work, e.g. in grant proposals, project reports, press releases and research assessment exercises. Specialised impact assessment studies can be difficult to replicate and may require resources and skills not available to individual researchers. Researchers are often hard-pressed to identify and describe research impacts and ad hoc accounts do not facilitate comparison across time or projects. METHODS: The Research Impact Framework was developed by identifying potential areas of health research impact from the research impact assessment literature and based on research assessment criteria, for example, as set out by the UK Research Assessment Exercise panels. A prototype of the framework was used to guide an analysis of the impact of selected research projects at the London School of Hygiene and Tropical Medicine. Additional areas of impact were identified in the process and researchers also provided feedback on which descriptive categories they thought were useful and valid vis-à-vis the nature and impact of their work. RESULTS: We identified four broad areas of impact: I. Research-related impacts; II. Policy impacts; III. Service impacts: health and intersectoral and IV. Societal impacts. Within each of these areas, further descriptive categories were identified. For example, the nature of research impact on policy can be described using the following categorisation, put forward by Weiss: Instrumental use where research findings drive policy-making; Mobilisation of support where research provides support for policy proposals; Conceptual use where research influences the concepts and language of policy deliberations and Redefining/wider influence where research leads to rethinking and changing established practices and beliefs. CONCLUSION: Researchers, while initially sceptical, found that the Research Impact Framework provided prompts and descriptive categories that helped them systematically identify a range of specific and verifiable impacts related to their work (compared to ad hoc approaches they had previously used). The framework could also help researchers think through implementation strategies and identify unintended or harmful effects. The standardised structure of the framework facilitates comparison of research impacts across projects and time, which is useful from analytical, management and assessment perspectives.

Evaluation Studies as Topic↗