The sublanguage of cross-coverage. (49/669)

At Columbia-Presbyterian Medical Center, free-text "Signout" notes are typed into the electronic record by clinicians for the purpose of cross-coverage. We plan to "unlock" information about adverse events contained in these notes in a subsequent project using Natural Language Processing (NLP). To better understand the requirements for parsing, Signout notes were compared to other common medical notes (ambulatory clinic notes and discharge summaries) on a series of quantitative metrics. They are shorter (mean length 59.25 words vs. 144.11 and 340.85 for ambulatory and discharge notes respectively) and use more abbreviations (26.88% vs. 20.07% and 3.57%). Despite being terser, Signout notes use less ambiguous abbreviations (8.34% vs. 9.09% and 18.02%). Differences were found using Relative Entropy and Squared Chi-square Distance in a novel fashion to compare these medical corpora. Signout notes appear to constitute a unique sublanguage of medicine. The implications for parsing free-text cross-coverage notes into coded medical data are discussed.  (+info)

Defining medical concepts by linguistic variables with fuzzy Arden Syntax. (50/669)

Diagnostic and therapeutic decisions in the domain of medicine usually depend on observed or measured data, such as observations made during an examination, or laboratory data. Furthermore, such decisions are often based on abstract domain knowledge. For decision-making, it is necessary to establish relationships between concrete data and abstract knowledge. These relationships can be defined in a formal way by fuzzy set theory. We extended the Arden Syntax for Medical Logic Systems, which can be used for decision support in the medical domain, to include concepts of fuzzy set theory. This paper presents extensions for defining linguistic variables by Arden Syntax, which can formalize different states of an abstract concept, such as different levels of blood glucose. Arden Syntax linguistic variables can be used within conditional expressions in decision rules or within fuzzy control rules for computer-aided diagnosis and therapy.  (+info)

The role of left inferior frontal and superior temporal cortex in sentence comprehension: localizing syntactic and semantic processes. (51/669)

An event-related functional magnetic resonance imaging (fMRI) paradigm was used to specify those brain areas supporting the processing of sentence-level semantic and syntactic information. Hemodynamic responses were recorded while participants listened to correct, semantically incorrect and syntactically incorrect sentences. Both anomalous conditions recruited larger portions of the superior temporal region than correct sentences. Processing of semantic violations relied primarily on the mid-portion of the superior temporal region bilaterally and the insular cortex bilaterally, whereas processing of syntactic violations specifically involved the anterior portion of the left superior temporal gyrus, the left posterior frontal operculum adjacent to Broca's area and the putamen in the left basal ganglia. A comparison of the two anomalous conditions revealed higher levels of activation for the syntactic over the semantic condition in the left basal ganglia and for the semantic over the syntactic condition in the mid-portion of the superior temporal gyrus, bilaterally. These data indicate that both semantic and syntactic processes are supported by a temporo-frontal network with distinct areas specialized for semantic and syntactic processes.  (+info)

Verb and auxiliary movement in agrammatic Broca's aphasia. (52/669)

Verb production in agrammatic Broca's aphasia has repeatedly been shown to be impaired by a number of investigators. Not only is the number of verbs produced often significantly reduced, but verb inflections and auxiliaries are often omitted as well (e.g., Bastiaanse, Jonkers, & Moltmaker-Osinga, 1996; Saffran, Berndt, & Schwartz, 1989; Thompson, Shapiro, Li, &Schendel, 1994, 1997). It has been suggested that these problems are, in part, caused by the fact that finite verbs need to be moved from their base-generated position to inflectional nodes in the syntactic tree (e.g., Bastiaanse & Van Zonneveld, 1998). Others have suggested that production deficits in agrammatism can be predicted based on the position that certain structures take in the syntactic tree (Friedmann & Grodzinsky, 1997; Hagiwara, 1995). If the former theory is correct, several predictions can be made. First of all, the discrepancy between production of finite verbs in the matrix and embedded clause that has been found for Dutch (Bastiaanse & Van Zonneveld, 1998) should not be observed in English, since the word order of the matrix and embedded clause are the same in the latter language. Second, if verb movement (including movement of auxiliaries) is problematic for speakers with agrammatic aphasia, then a hierarchy in the production of auxiliaries in yes/no questions, auxiliaries, and finite verbs in declarative sentences in English would be expected, since the former has been moved and the two latter are in base-generated position. In the present paper, these hypotheses were tested in a cross-linguistic study of Dutch and English. Results showed the position in the syntactic tree does not predict deficit patterns; rather the critical factor appears to relate to whether or not verb or auxiliary movement is required.  (+info)

The language system in schizophrenia: effects of capacity and linguistic structure. (53/669)

Dysfunction in receptive language processes has been reliably observed in individuals diagnosed with schizophrenia and their first degree family members. The present study addressed the unresolved issue of whether receptive syntax is intact in schizophrenia. The principal question concerned whether comprehension dysfunction in schizophrenia involves a disturbance in the processing of syntactic structure, a susceptibility to demands placed on temporal auditory processing, or some combination of these two general factors. Comprehension accuracy was compared between 32 males diagnosed with schizophrenia and 22 males with no lifetime diagnosis of psychiatric disorder. Accuracy was examined for responses to Who questions ("Who did X?" and "Who was done X?") about information in the sentential clauses (main vs. relative) of two types of relative sentences (subject-relatives vs. object-relatives) that were presented aurally at conversational and accelerated rates. The relationship between cognitive functions and comprehension accuracy was also tested. Results showed highly significant effects of diagnosis, syntactic structure, and temporal demand. Patients were characterized by reduced overall comprehension accuracy compared to controls. More important, patients and controls differed in their patterns of accuracy across the different types of syntactic structure. Finally, cognitive functions predicted but did not completely account for comprehension accuracy. Findings suggest the hypothesis that receptive syntax is disrupted in schizophrenia, and this dysfunction may not be entirely explained by compromised general cognitive ability.  (+info)

An event-related fMRI study of explicit syntactic processing of normal/anomalous sentences in contrast to implicit syntactic processing. (54/669)

Using event-related functional magnetic resonance imaging (fMRI), we examined activation of cortical language areas for explicit syntactic processing. In a syntactic decision (Syn) task, the participants judged whether the presented sentence was syntactically correct, where syntactic knowledge about the distinction between transitive and intransitive verbs was required. In a semantic decision (Sem) task, lexico-semantic knowledge about selectional restrictions was indispensable. In a phonological decision (Pho) task, phonological knowledge about accent patterns was required. The Sem and Pho tasks involved implicit syntactic processing, as well as explicit semantic and phonological processing, respectively. We also tested a voice-pitch comparison (Voi) task in which no explicit linguistic knowledge was required. In the direct comparison of Syn - (Sem + Pho + Voi), we found localized activation in the left inferior frontal gyrus (F3op/F3t), indicating that activation of the left F3op/F3t is more prominently enhanced in explicit syntactic processing than in implicit syntactic processing. Moreover, we determined that its activation is selective to syntactic judgments regarding both normal and anomalous sentences. These results suggest that explicit information processing in the syntactic domain critically involves the left F3op/F3t, which is functionally separable from other regions.  (+info)

Doctor-patient communication: a comparison of the USA and Japan. (55/669)

BACKGROUND: Little is known about the differences and similarities between doctor-patient communication patterns in different cultures. OBJECTIVES: The aim of this study was to examine communication patterns of doctor-patient consultations in two different cultures, namely the USA and Japan, and to elucidate linguistic differences and similarities in communication. METHODS: This cross-sectional study used quantitative discourse analysis from linguistics to compare 40 doctor-patient consultations: 20 out-patient consultations of five physicians in the USA and 20 out-patient consultations of four physicians in Japan. The main outcomes measured were time spent in each phase of the encounter, number of categorized speech acts, distribution of question types and frequencies of back-channel responses and interruptions. RESULTS: The average length of doctor-patient encounters was 668.7 s in the USA and 505 s in Japan. US physicians spent relatively more time on treatment and follow-up talk (31%) and social talk (12%), whereas the Japanese had longer physical examinations (28%) and diagnosis or consideration talk (15%). Japanese doctor-patient conversations included more silence (30%) than those in the USA (8.2%). The doctor-patient ratios of total speech acts were similar (USA 55% versus 45%; Japan 59% versus 41%). Physicians in both countries controlled communication during encounters by asking more questions than the patients (75% in the USA; 78% in Japan). The Japanese physicians and patients used back-channel responses and interruptions more often than those in the USA. CONCLUSIONS: While doctor-patient communication differed between the USA and Japan in the proportion of time spent in each phase of the encounter, length of pauses and the use of back-channel responses and interruptions, physician versus patient ratios of questions and other speech acts were similar. The variations may reflect cultural differences, whereas the similarities may reflect professional specificity stemming from the shared needs to fill the information gap between physician and patient. Adequate awareness of these differences and similarities could be used to educate clinicians about the best approaches to patients from particular cultural backgrounds.  (+info)

Status of Austro-Asiatic groups in the peopling of India: An exploratory study based on the available prehistoric, linguistic and biological evidences. (56/669)

Among the most contentious currently debated issues is about the people who had settled first in the Indian subcontinent. It has been suggested that the communities affiliated to the Austro-Asiatic linguistic family are perhaps the first to settle in India and the palaeoanthropological evidences suggest the earliest settlement probably around 60,000 years BP. Recent speculations, based on both traditional genetic markers and DNA markers, seem to corroborate the aforesaid view. However, these studies are inadequate both in terms of the representation of the constituent groups within this broad linguistic category as well as the number of samples that represent each of them. We strongly feel that, before making any formidable conclusions on the peopling of India and/or the history of settlement, it is necessary to ascertain that the Austro-Asiatic speakers, represented by over 30 different tribal groups, either genetically constitute a homogenous single entity or are a heterogeneous conglomeration, derived from different sources. As a first step towards this we tried to collate and analyse the existing information geographic, ethno-historic, cultural and biological. The results of the analyses of anthropometric and genetic marker data indicate that the Austro-Asiatic groups, particularly the Mundari speakers, with certain exceptions, show greater homogeneity among them when compared to the other linguistic groups, although certain groups show as outliers. However, traditional genetic markers show lower within population heterozygosity compared to Dravidian and other Indian populations. This is contrary to what has been claimed in case of certain DNA markers. Given that relatively greater heterozygosity among the Austro-Asiatic populations has been taken as one of the important evidences supporting greater antiquity of these populations one should await results of detailed DNA studies being currently undertaken by us, involving a number of Austro-Asiatic and other ethnic populations of India to resolve the issue unequivocally.  (+info)