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L Frazier

Publications and source records attributed to L Frazier.

At least 37 records · Page 2Linked to original sources
PubMed1995

Constraint satisfaction as a theory of sentence processing.

Various problems with the constraint satisfaction model are discussed. It is argued that the empirical evidence presented in support of the model does not concern predictions of the model that diverge from those of depth-first (one analysis at a time) models. Several methodological problems are also noted. As a theory of sentence processing, the model is inadequate. It fails to account for the assignment of local structure, global structure, structure involving discontinuous dependencies, long-distance dependencies, and adjunct phrases. It makes incorrect predictions about the timing of syntactic analysis. Further, because syntactic structure is available only through activation of syntactic projections stored in the lexical entry of words, the model leaves entirely unexplained the myriad psycholinguistic findings demonstrating independence of lexical and syntactic structure (in Event Related Potential studies, code-switching, pure syntactic priming, etc). Finally, the model is not restrictive or explanatory, providing an account that largely consists of post hoc correlations between frequency counts or subjects' ratings of sentences and processing time data for the same sentences.

Automatism↗
PubMed1995

Argument structure and association preferences in Spanish and English complex NPs.

Three questionnaire studies investigated Spanish and English readers' interpretations of sentences with complex noun phrases (NPs) such as "I really liked the preface of the book that I read yesterday." These complex NPs are ambiguous between two readings, one in which the relative clause (RC) that I read yesterday modifies the first noun, N1, preface, or the second noun, N2, book. Cuetos and Mitchell (Cognition, 1988, 30, 73-105) claimed that Spanish was biased toward having the RC modify N1, which they claimed was evidence against the cross-language universality of the late closure parsing principle. We demonstrate that the preference for N1 versus N2 modification varies greatly between different construction types within both Spanish and English while the variation between languages is relatively minor, but still of interest. The effect cannot be reduced to an effect of plausibility, but seems to reflect directly certain syntactic and semantic aspects of the constructions studied. We claim that relative clauses and other "nonprimary" phrases are not parsed following such parsing principles as late closure, but instead follow principles we advance in the form of the construal hypothesis. Thus, it is not the case that late closure is a language-specific strategy; rather, it and similar structural parsing principles are specific to only certain classes of phrases within a language.

Language↗
PubMed1995

Cultural paradoxes relating to sexuality and breastfeeding.

Despite the widely acknowledged evidence supporting the benefits of breastfeeding, the prevalence and duration of breastfeeding in the United States and other Western countries remain low. To investigate this phenomenon, we conducted an analysis of the socio-cultural factors that influence women's infant-feeding decisions and examined how breastfeeding is treated in the mass media and by U.S. legislation. We found that cultural notions of the female breast as a primarily sexual object place the act of breastfeeding in a controversial light and can be one of the most influential factors in a woman's decision not to breastfeed. This notion is often supported by the media and legislation. Further research needs to focus on the relationship between sexuality and breastfeeding to help our understanding of breastfeeding behavior. This research should assist policymakers and health workers in their efforts to protect and promote breastfeeding and to increase its social acceptability.

Attitude to Health↗
PubMed1993

Processing Dutch sentence structures.

This paper summarizes existing research on syntactic processing of Dutch sentences by adult native speakers of the language, with an eye to the implications of this work for a general theory of the human sentence processing mechanism (HSPM). The principles underlying the assignment of phrase structure and the binding of traces seem to be the same as those proposed for languages like English or Italian. For example, no delays of analysis exist in parsing the constituents of a phrase even if the phrase is head-final. Also, the obligatory topicalization of a constituent which is required in the highest clause of a Dutch sentence does not appear to result in trace postulation principles distinct from those operative in languages where topicalization is optional. The studies reviewed also address questions concerning the complexity of the dependency between a moved constituent and its trace as measured by the length of a path vs. the length of a chain, the processing of subject gaps following an overt complementizer, the complexity of interpreting an adjunct moved from an obligatory position, and the processing of discontinuous words. Though the studies do not pose a problem for pre-existing views of the HSPM, they do highlight certain areas of parsing theory which remain seriously underdeveloped. Foremost, perhaps, is the specification of the principles governing the architecture of the processing system, which ultimately should explain how the organization of the HSPM and its subcomponents results from acquiring the grammar of any particular language.

Animals↗
PubMed1993

Processing discontinuous words: on the interface between lexical and syntactic processing.

How are discontinuous words processed? Are they identified in the lexicon or in the syntax? Schreuder (1990) proposes the existence of morphological integration nodes (MI nodes) to account for the representation of complex verbs with separable prefixes in Dutch. We tested the MI model during sentence processing in Dutch, using an ungrammaticality judgment task. The results supported the predictions of the Schreuder model, and also provide evidence for distinct lexical/morphological and syntactic processing subsystems, each driven by the information resources and tasks relevant to its own representational vocabulary. It is argued that no special principles are needed to govern the interaction of lexical/morphological and syntactic processing, even for the identification of discontinuous words; this follows automatically from independently required characterizations of the subsystems themselves. We also examine the principles underlying the MI model in an attempt to extend the model to a wider array of constructions and languages. It is hypothesized that frequently encountered linguistic expressions are represented in the lexicon. In the basic case, they are represented as access nodes, if they may stand alone, and as MI nodes, if their constituents are already represented by access nodes. Unlike the original MI model, no further stipulation is needed concerning the existence or inhibition properties of MI nodes, assuming that candidate lexical/morphological hypotheses are appended to whatever portion(s) of the input string they are hypotheses about.

Adult↗
PubMed1992

A gamma delta+ T-cell leukemia bearing a novel t(8;14)(q24;q11) translocation demonstrates spontaneous in vitro natural killer-like activity.

A highly malignant human T-cell leukemia was identified by cell surface analysis as a member of the T-cell receptor (TCR) gamma delta lineage. Cytogenetic and molecular analysis showed a novel t(8;14)(q24;q11) rearrangement involving the J delta 1 gene segment on chromosome 14 and the distal end of chromosome 8 near the c-myc proto-oncogene locus. The gamma delta TCR of the leukemia blasts was functionally intact and could be activated to generate intracellular calcium flux and to target Fc receptor-mediated redirected tumor cell lysis. In addition, non-major histocompatibility complex restricted lysis of a limited target cell panel was shown by fresh leukemic blasts and by the in vitro-maintained leukemia cells that was comparable to known T-cell lines with natural killer-like activity. These data suggest that the T-cell leukemia potentially had in vivo functional cytolytic activity. However, whether this activity did contribute to the patient's clinical condition could not be determined.

Antigens, CD↗
PubMed1992

Thematic analysis in agrammatic comprehension: syntactic structures and task demands.

Aphasics' ability to assign thematic roles during sentence comprehension was investigated. The study was motivated by the hypothesis that capacity limitations, e.g., due to slowed processing operations, interact systematically with certain aspects of structural analysis more than with others. Experiments using a sentence-picture matching paradigm were conducted with several agrammatic Broca's and paragrammatic Wernicke's patients. Experiment 1 tested comprehension of various syntatic structures. The astoundingly good performance in Experiment 1 for both patient groups was attributed to the low task demands of the experiment. Raising the task demands, by delaying presentation of the relevant picture set in Experiment 2, resulted in a significant decrement of comprehension performance for agrammatic Broca's aphasics, but not for Wernicke's aphasics. Putting the main verb in the sentence-final position, as in Experiment 3, affected Wernicke's aphasics', but not Broca's aphasics' performance. In principle, one explanation for the performance differences between Experiments 1 and 2 for Broca's patient might be a deficit in these patients' verbal memory capacity. Therefore, verbal memory span on different word categories was tested in an additional experiment. No difference, however, was found between the Broca's patients' and the Wernicke's patients' capacity for verbal memory despite their different sentence comprehension profiles. The present data are taken to support the view that Broca's aphasics' comprehension behavior is due to the processing demands imposed by structural inference chains and not to a general reduction in verbal memory.

Adult↗
PubMed1991

On deriving the properties of agrammatic comprehension.

Several recent studies characterize agrammatic comprehension as a computational rather than a conceptual deficit. A restriction in the computational capacity of the processor may affect sentence comprehension performance unevenly due to the varying demands imposed by different sentence structures and different tasks. It is argued that structures involving longer inferential chains suffer greater degradation than structures involving shorter inferential chains. Many of the observed properties of agrammatic comprehension may be seen to follow from this principle alone.

Aphasia, Broca↗
PubMed1989

Selection mechanisms in reading lexically ambiguous words.

Readers' eye movements were monitored as they read sentences containing lexically ambiguous words. The ambiguous words were either biased (one strongly dominant interpretation) or nonbiased. Readers' gaze durations were longer on nonbiased than biased words when the disambiguating information followed the target word. In Experiment 1, reading times on the disambiguating word did not differ whether the disambiguation followed the target word immediately or occurred several words later. In Experiment 2, prior disambiguation eliminated the long gaze durations on nonbiased target words but resulted in long gaze durations on biased target words if the context demanded the subordinate meaning. The results indicate that successful integration of one meaning with prior context terminates the search for alternative meanings of that word. This results in selective (single meaning) access when integration of a dominant meaning is fast (due to a biasing context) and identification of a subordinate meaning is slow (a strongly biased ambiguity with a low-frequency meaning).

Adult↗
PubMed1986

The use of syntactic information in filling gaps.

Two sentence-comprehension time experiments replicated and extended previously reported research indicating that readers initially make a quick, heuristic assignment of fillers to gaps in temporarily ambiguous sentences such as "Who did John beg to sing?" and "Who did John beg to sing for?" The Most Recent Filler heuristic readers seemed to adopt made the former "distant filler" sentence harder to comprehend than the latter "recent filler" sentence. Readers did not in general use all available sources of information in making this assignment. In particular, they usually delayed their use of verb control information so that substituting the unambiguous-control verbs "force" or "begin" for "beg" did not eliminate the distant filler inferiority. The experiments counter some criticisms that have been made of the previously reported research. The possibility that readers delay using an interesting natural category of information was raised, and its implications for the mental grammar were considered.

Humans↗
PubMed1983

Arterial lesions and blood lipids in rhesus monkeys fed human diets.

The results of three consecutive experiments are reported in which atherosclerotic lesions of adult male rhesus monkeys produced by a ration relatively rich in calories, cholesterol, and saturated fats and resembling the "average American" table-prepared fare were compared with the atherosclerotic lesions in similar monkeys fed a low-fat, low-cholesterol, and low-calorie, so-called "prudent" table-prepared ration. Each experiment lasted 2 years. The frequency and severity of gross and microscopic aortic atheromatous disease and microscopic coronary artery disease were compared. In addition, the qualitative features of the lesions, several types of analyses of blood lipids, and the reactions of aortic cells to in vivo deposited interstitial aortic deposits of lipoprotein fractions prepared from these animals are described. In general, the animals fed the average American ration had serum cholesterols that were consistently higher (383 +/- 35 mg%) than animals fed the prudent ration (199 +/- 13 mg%). The contrasts in lesion involvement varied from about 6:1 in severity for both aortic and coronary lesions to approximately 3:1 or 4:1 in frequency. The aortic gross surface area involvement at autopsy was 46% for monkeys fed the average American ration compared to 7% for the prudent diet group. In lesions of animals fed the average American ration much of the lipid was extracellular and both cell proliferation and fiber protein deposition were prominent. The small lesions in the animals fed the prudent ration were much more likely to be composed mostly of "foam cell" intimal thickenings. The lesions seen in the animals fed the average American ration resemble those seen in autopsies of many young Americans whose lesions have been studied recently and who demonstrate raised lesions in their coronary arteries and aortas in the third decade.

Animals↗
PubMed1982

Respiratory and Nitrogenase Activities of Soybean Nodules Formed by Hydrogen Uptake Negative (Hup) Mutant and Revertant Strains of Rhizobium japonicum Characterized by Protein Patterns.

Rates of respiratory CO(2) loss and nitrogenase activities of H(2) uptake-negative mutant strains and H(2) uptake-positive revertant strains of Rhizobium japonicum have been investigated. Two-dimensional gel protein patterns of bacteroids formed by inoculation of soybeans (Glycine max L.) with these two strains show that they are closely related and revealed only one obvious difference between them. On the basis of molecular weight standards, it was concluded that the missing protein spot in the H(2) uptake-negative mutant strain could be caused by a failure of the mutant to synthesize hydrogenase. Nodules formed by the H(2) uptake-negative mutant strain evolved respiratory CO(2) at a rate of about 10% higher than that of nodules formed by the H(2) uptake-positive revertant strain. During short-term experiments employed, rates of both C(2)H(2) reduction and (15)N(2) fixation varied considerably among replicate samples and no statistically significant differences between mutant and revertant strains were observed. It was observed that increasing the partial pressure of O(2) over nodules significantly decreased the proportion of nitrogenase electrons allocated to H(+).

Journal Article↗