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1.
Proc Natl Acad Sci U S A ; 121(30): e2315438121, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39028693

RESUMEN

There is evidence from both behavior and brain activity that the way information is structured, through the use of focus, can up-regulate processing of focused constituents, likely to give prominence to the relevant aspects of the input. This is hypothesized to be universal, regardless of the different ways in which languages encode focus. In order to test this universalist hypothesis, we need to go beyond the more familiar linguistic strategies for marking focus, such as by means of intonation or specific syntactic structures (e.g., it-clefts). Therefore, in this study, we examine Makhuwa-Enahara, a Bantu language spoken in northern Mozambique, which uniquely marks focus through verbal conjugation. The participants were presented with sentences that consisted of either a semantically anomalous constituent or a semantically nonanomalous constituent. Moreover, focus on this particular constituent could be either present or absent. We observed a consistent pattern: Focused information generated a more negative N400 response than the same information in nonfocus position. This demonstrates that regardless of how focus is marked, its consequence seems to result in an upregulation of processing of information that is in focus.


Asunto(s)
Lenguaje , Humanos , Femenino , Masculino , Adulto , Mozambique , Electroencefalografía , Semántica , Encéfalo/fisiología , Adulto Joven , Lingüística , Potenciales Evocados/fisiología
2.
Cereb Cortex ; 34(2)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38314589

RESUMEN

Sentence comprehension is highly practiced and largely automatic, but this belies the complexity of the underlying processes. We used functional neuroimaging to investigate garden-path sentences that cause difficulty during comprehension, in order to unpack the different processes used to support sentence interpretation. By investigating garden-path and other types of sentences within the same individuals, we functionally profiled different regions within the temporal and frontal cortices in the left hemisphere. The results revealed that different aspects of comprehension difficulty are handled by left posterior temporal, left anterior temporal, ventral left frontal, and dorsal left frontal cortices. The functional profiles of these regions likely lie along a spectrum of specificity to generality, including language-specific processing of linguistic representations, more general conflict resolution processes operating over linguistic representations, and processes for handling difficulty in general. These findings suggest that difficulty is not unitary and that there is a role for a variety of linguistic and non-linguistic processes in supporting comprehension.


Asunto(s)
Comprensión , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Lenguaje , Lingüística , Neuroimagen Funcional , Mapeo Encefálico
3.
J Neurosci ; 43(24): 4461-4469, 2023 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-37208175

RESUMEN

Neural oscillations are thought to support speech and language processing. They may not only inherit acoustic rhythms, but might also impose endogenous rhythms onto processing. In support of this, we here report that human (both male and female) eye movements during naturalistic reading exhibit rhythmic patterns that show frequency-selective coherence with the EEG, in the absence of any stimulation rhythm. Periodicity was observed in two distinct frequency bands: First, word-locked saccades at 4-5 Hz display coherence with whole-head theta-band activity. Second, fixation durations fluctuate rhythmically at ∼1 Hz, in coherence with occipital delta-band activity. This latter effect was additionally phase-locked to sentence endings, suggesting a relationship with the formation of multi-word chunks. Together, eye movements during reading contain rhythmic patterns that occur in synchrony with oscillatory brain activity. This suggests that linguistic processing imposes preferred processing time scales onto reading, largely independent of actual physical rhythms in the stimulus.SIGNIFICANCE STATEMENT The sampling, grouping, and transmission of information are supported by rhythmic brain activity, so-called neural oscillations. In addition to sampling external stimuli, such rhythms may also be endogenous, affecting processing from the inside out. In particular, endogenous rhythms may impose their pace onto language processing. Studying this is challenging because speech contains physical rhythms that mask endogenous activity. To overcome this challenge, we turned to naturalistic reading, where text does not require the reader to sample in a specific rhythm. We observed rhythmic patterns of eye movements that are synchronized to brain activity as recorded with EEG. This rhythmicity is not imposed by the external stimulus, which indicates that rhythmic brain activity may serve as a pacemaker for language processing.


Asunto(s)
Tecnología de Seguimiento Ocular , Lectura , Masculino , Humanos , Femenino , Electroencefalografía , Periodicidad , Lenguaje
4.
J Neurosci ; 43(20): 3718-3732, 2023 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-37059462

RESUMEN

Brain oscillations are prevalent in all species and are involved in numerous perceptual operations. α oscillations are thought to facilitate processing through the inhibition of task-irrelevant networks, while ß oscillations are linked to the putative reactivation of content representations. Can the proposed functional role of α and ß oscillations be generalized from low-level operations to higher-level cognitive processes? Here we address this question focusing on naturalistic spoken language comprehension. Twenty-two (18 female) Dutch native speakers listened to stories in Dutch and French while MEG was recorded. We used dependency parsing to identify three dependency states at each word: the number of (1) newly opened dependencies, (2) dependencies that remained open, and (3) resolved dependencies. We then constructed forward models to predict α and ß power from the dependency features. Results showed that dependency features predict α and ß power in language-related regions beyond low-level linguistic features. Left temporal, fundamental language regions are involved in language comprehension in α, while frontal and parietal, higher-order language regions, and motor regions are involved in ß. Critically, α- and ß-band dynamics seem to subserve language comprehension tapping into syntactic structure building and semantic composition by providing low-level mechanistic operations for inhibition and reactivation processes. Because of the temporal similarity of the α-ß responses, their potential functional dissociation remains to be elucidated. Overall, this study sheds light on the role of α and ß oscillations during naturalistic spoken language comprehension, providing evidence for the generalizability of these dynamics from perceptual to complex linguistic processes.SIGNIFICANCE STATEMENT It remains unclear whether the proposed functional role of α and ß oscillations in perceptual and motor function is generalizable to higher-level cognitive processes, such as spoken language comprehension. We found that syntactic features predict α and ß power in language-related regions beyond low-level linguistic features when listening to naturalistic speech in a known language. We offer experimental findings that integrate a neuroscientific framework on the role of brain oscillations as "building blocks" with spoken language comprehension. This supports the view of a domain-general role of oscillations across the hierarchy of cognitive functions, from low-level sensory operations to abstract linguistic processes.


Asunto(s)
Comprensión , Percepción del Habla , Femenino , Humanos , Comprensión/fisiología , Magnetoencefalografía , Encéfalo/fisiología , Lenguaje , Lingüística , Mapeo Encefálico/métodos , Percepción del Habla/fisiología
5.
J Cogn Neurosci ; 32(5): 747-761, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31851593

RESUMEN

There is a range of variability in the speed with which a single speaker will produce the same word from one instance to another. Individual differences studies have shown that the speed of production and the ability to maintain attention are related. This study investigated whether fluctuations in production latencies can be explained by spontaneous fluctuations in speakers' attention just prior to initiating speech planning. A relationship between individuals' incidental attentional state and response performance is well attested in visual perception, with lower prestimulus alpha power associated with faster manual responses. Alpha is thought to have an inhibitory function: Low alpha power suggests less inhibition of a specific brain region, whereas high alpha power suggests more inhibition. Does the same relationship hold for cognitively demanding tasks such as word production? In this study, participants named pictures while EEG was recorded, with alpha power taken to index an individual's momentary attentional state. Participants' level of alpha power just prior to picture presentation and just prior to speech onset predicted subsequent naming latencies. Specifically, higher alpha power in the motor system resulted in faster speech initiation. Our results suggest that one index of a lapse of attention during speaking is reduced inhibition of motor-cortical regions: Decreased motor-cortical alpha power indicates reduced inhibition of this area while early stages of production planning unfold, which leads to increased interference from motor-cortical signals and longer naming latencies. This study shows that the language production system is not impermeable to the influence of attention.


Asunto(s)
Ritmo alfa/fisiología , Atención/fisiología , Corteza Motora/fisiología , Inhibición Neural/fisiología , Reconocimiento Visual de Modelos/fisiología , Tiempo de Reacción/fisiología , Habla/fisiología , Adulto , Femenino , Humanos , Masculino , Psicolingüística , Adulto Joven
6.
Am J Epidemiol ; 189(10): 1011-1015, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32602537

RESUMEN

The positive effects of increased diversity and inclusion in scientific research and practice are well documented. In this issue, DeVilbiss et al. (Am J Epidemiol. 2020;189(10):998-1010) present findings from a survey used to collect information to characterize diversity among epidemiologists and perceptions of inclusion in the epidemiologic profession. They capture identity across a range of personal characteristics, including race, gender, socioeconomic background, sexual orientation, religion, and political leaning. In this commentary, we assert that the inclusion of political leaning as an axis of identity alongside the others undermines the larger project of promoting diversity and inclusion in the profession and is symptomatic of the movement for "ideological diversity" in higher education. We identify why political leaning is not an appropriate metric of diversity and detail why prioritizing ideological diversity counterintuitively can work against equity building initiatives. As an alternative to ideological diversity, we propose that epidemiologists take up an existing framework for research and practice that centers the voices and perspectives of historically marginalized populations in epidemiologic work.


Asunto(s)
Diversidad Cultural , Epidemiología/organización & administración , Política
7.
J Org Chem ; 81(15): 6816-9, 2016 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-27387821

RESUMEN

We investigate the effect of buffer identity, ionic strength, pH, and organic cosolvents on the rate of strain-promoted azide-alkyne cycloaddition with the widely used DIBAC cyclooctyne. The rate of reaction between DIBAC and a hydrophilic azide is highly tolerant to changes in buffer conditions but is impacted by organic cosolvents. Thus, bioconjugation reactions using DIBAC can be carried out in the buffer that is most compatible with the biomolecules being labeled, but the use of organic cosolvents should be carefully considered.

8.
Int J Mol Sci ; 17(12)2016 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-27916801

RESUMEN

With a growing need for sustainable resources research has become highly interested in investigating the structure and physical properties of biomaterials composed of natural macromolecules. In this study, we assessed the structural, morphological, and thermal properties of blended, regenerated films comprised of cellulose, lignin, and hemicellulose (xylan) using the ionic liquid 1-allyl-3-methylimidazolium chloride (AMIMCl). Attenuated total reflectance Fourier transform infrared (ATR-FTIR) analysis, scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray scattering, and thermogravimetric analysis (TGA) were used to qualitatively and quantitatively measure bonding interactions, morphology, and thermal stability of the regenerated films. The results demonstrated that the regenerated films' structural, morphological, and thermal character changed as a function of lignin-xylan concentration. The decomposition temperature rose according to an increase in lignin content and the surface topography of the regenerated films changed from fibrous to spherical patterns. This suggests that lignin-xylan concentration alters the self-assembly of lignin and the cellulose microfibril development. X-ray scattering confirms the extent of the morphological and molecular changes. Our data reveals that the inter- and intra-molecular interactions with the cellulose crystalline domains, along with the amount of disorder in the system, control the microfibril dimensional characteristics, lignin self-assembly, and possibly the overall material's structural and thermal properties.


Asunto(s)
Materiales Biocompatibles/química , Celulosa/química , Líquidos Iónicos/química , Lignina/química , Polisacáridos/química , Temperatura , Resistencia a la Tracción , Termogravimetría
9.
Environ Manage ; 58(1): 117-29, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27017517

RESUMEN

Throughout the developing world, mobile phones are spreading rapidly into rural areas where subsistence livelihoods, biodiversity conservation, and human-wildlife conflict (HWC) are each common. Despite this trend, little is known about the relationship between mobile phones and HWC in conservation landscapes. This paper examines this relationship within ethnically Maasai communities in northern Tanzania on the border of Tarangire National Park. Mixed qualitative and quantitative methods of data collection and analysis are used to (1) describe how Maasai agro-pastoralists use phones to manage human-wildlife interactions; and (2) assess the relationship between phone use and measures of HWC, controlling for other factors. The findings indicate that households use phones to reduce the number and severity of HWC events and that the relationship between phones and HWC varies according to the type of HWC.


Asunto(s)
Animales Salvajes , Teléfono Celular/tendencias , Conflicto Psicológico , Conservación de los Recursos Naturales , Animales , Animales Salvajes/psicología , Biodiversidad , Teléfono Celular/estadística & datos numéricos , Conservación de los Recursos Naturales/métodos , Conservación de los Recursos Naturales/estadística & datos numéricos , Recolección de Datos , Humanos , Percepción , Riesgo , Población Rural , Tanzanía
10.
Neuroimage ; 109: 50-62, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25583610

RESUMEN

EEG mu rhythms (8-13 Hz) recorded at fronto-central electrodes are generally considered as markers of motor cortical activity in humans, because they are modulated when participants perform an action, when they observe another's action or even when they imagine performing an action. In this study, we analyzed the time-frequency (TF) modulation of mu rhythms while participants read action language ("You will cut the strawberry cake"), abstract language ("You will doubt the patient's argument"), and perceptive language ("You will notice the bright day"). The results indicated that mu suppression at fronto-central sites is associated with action language rather than with abstract or perceptive language. Also, the largest difference between conditions occurred quite late in the sentence, while reading the first noun, (contrast Action vs. Abstract), or the second noun following the action verb (contrast Action vs. Perceptive). This suggests that motor activation is associated with the integration of words across the sentence beyond the lexical processing of the action verb. Source reconstruction localized mu suppression associated with action sentences in premotor cortex (BA 6). The present study suggests (1) that the understanding of action language activates motor networks in the human brain, and (2) that this activation occurs online based on semantic integration across multiple words in the sentence.


Asunto(s)
Ondas Encefálicas , Encéfalo/fisiología , Comprensión/fisiología , Lenguaje , Movimiento , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Corteza Motora/fisiología , Lectura , Análisis Espectral , Adulto Joven
11.
J Am Pharm Assoc (2003) ; 54(5): 502-9, 2 p following 509, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25216880

RESUMEN

OBJECTIVES: To characterize pregnancy and lactation-related medication inquiries to a drug information center to identify classes of medications of most concern to providers. A secondary objective was to identify any trends in provider inquiries over the study period. DESIGN: A retrospective descriptive study of pregnancy and lactation-related inquiries to the University of North Carolina Health Care System Drug Information Center database between January 2001 and December 2010. SETTING: University of North Carolina Health Care System Drug Information Center. INTERVENTION: Provider inquiries and responses were extracted and characterized by indication for treatment and reason for inquiry. Comparison of the first and second 5-year periods was performed to delineate trends. Descriptive statistics, Fisher's Exact and χ2 tests were used for analysis. MAIN OUTCOME MEASURES: Inquiry origin, time, and subject. RESULTS: 433 inquiries were retrieved over the study period from physicians (50%), pharmacists (21%), and nurses (18%). Inquiries were most often made during the antepartum period (34%), followed by the postpartum (28%) and preconception (22%) periods. The most frequent indications for inquiry were psychiatry (15%) and infectious diseases (14%), which remained constant throughout the study period. Safety was the most common reason for inquiry (52%). The responses provided to callers were limited due to lack of information availability 37% of the time. CONCLUSION: Psychiatry and infectious disease-related indications are the most frequent subjects of provider inquiry regarding medication use in pregnancy. Rates of inquiry remained constant throughout the past decade in most therapeutic areas. These findings are consistent with previous observations in other developed countries and suggest high-yield areas for pharmacist education.


Asunto(s)
Bases de Datos Farmacéuticas/estadística & datos numéricos , Servicios de Información sobre Medicamentos/estadística & datos numéricos , Lactancia , Complicaciones del Embarazo/tratamiento farmacológico , Femenino , Humanos , North Carolina , Enfermeras y Enfermeros/estadística & datos numéricos , Preparaciones Farmacéuticas/administración & dosificación , Farmacéuticos/estadística & datos numéricos , Médicos/estadística & datos numéricos , Embarazo , Estudios Retrospectivos , Universidades
12.
Brain Res ; 1838: 148993, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38729334

RESUMEN

Previous studies, using the Continuous Flash Suppression (CFS) paradigm, observed that (Western) university students are better able to detect otherwise invisible pictures of objects when they are presented with the corresponding spoken word shortly before the picture appears. Here we attempted to replicate this effect with non-Western university students in Goa (India). A second aim was to explore the performance of (non-Western) meditators practicing Sudarshan Kriya Yoga in Goa in the same task. Some previous literature suggests that meditators may excel in some tasks that tap visual attention, for example by exercising better endogenous and exogenous control of visual awareness than non-meditators. The present study replicated the finding that congruent spoken cue words lead to significantly higher detection sensitivity than incongruent cue words in non-Western university students. Our exploratory meditator group also showed this detection effect but both frequentist and Bayesian analyses suggest that the practice of meditation did not modulate it. Overall, our results provide further support for the notion that spoken words can activate low-level category-specific visual features that boost the basic capacity to detect the presence of a visual stimulus that has those features. Further research is required to conclusively test whether meditation can modulate visual detection abilities in CFS and similar tasks.


Asunto(s)
Estudiantes , Yoga , Humanos , Yoga/psicología , Masculino , Femenino , Adulto Joven , Adulto , Estudiantes/psicología , Percepción Visual/fisiología , Atención/fisiología , Estimulación Luminosa/métodos , Percepción del Habla/fisiología , Meditación/métodos , Meditación/psicología , Señales (Psicología) , Adolescente
13.
Science ; 385(6711): 831-833, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39172825

RESUMEN

Governments should evaluate advanced models and if needed impose safety measures.


Asunto(s)
Inteligencia Artificial , Bioaseguramiento , Humanos , Modelos Biológicos , Personal Administrativo , Gobierno
14.
Humanit Soc Sci Commun ; 10(1): 10, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36628103

RESUMEN

By employing a retrospective collaborative autoethnographic approach, this work aims to better understand how an interdisciplinary context shaped the authors' experiences of British academia during their Ph.D research. The authors bring together their individual observations and experiences to collectively interrogate and critically reflect on their position as postgraduate researchers (PGRs) on a collaborative interdisciplinary research project. These reflections are taken as a lens through which to interrogate the contemporary British university. Pre-existing tensions within the academy are characterised as 'asymmetries' along dimensions of risk, disciplinary hierarchy, and knowledge. It is argued that the authors' experience of uncertainty and precarity as junior academics stems principally from pre-existing structures within British academia, rather than the interdisciplinary environment in which they were immersed. By emphasising the role of the successfully trained doctoral candidate as an outcome itself, it is argued that indicators of success can be reframed, shifting the power asymmetry to place greater value on PGRs within the neoliberal academy. Highlighting the ambiguity of their convergent and divergent personal experiences, the authors suggest there is a need for a greater focus on the contested role of the PGR within the contemporary university system.

15.
JAMA Health Forum ; 4(9): e233197, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37738064

RESUMEN

Importance: Medicaid patients with mental illness comprise one of the most high-need and complex patient populations. Value-based reforms aim to improve care, but their efficacy in the Medicaid program is unclear. Objective: To investigate if New York state's Medicaid value-based payment reform was associated with improved utilization patterns for patients with mental illness. Design, Setting, and Participants: This retrospective cohort study used a difference-in-differences analysis to compare changes in utilization between Medicaid beneficiaries whose outpatient practices participated in value-based payment reform and beneficiaries whose practices did not participate from before (July 1, 2013-June 30, 2015) to after reform (July 1, 2015-June 30, 2019). Participants were Medicaid beneficiaries in New York state aged 18 to 64 years with major depression disorder, bipolar disorder, and/or schizophrenia. Data analysis was performed from April 2021 to July 2023. Exposure: Beneficiaries were exposed to value-based payment reforms if their attributed outpatient practice participated in value-based payment reform at baseline (July 1, 2015). Main Outcomes and Measures: Primary outcomes were the number of outpatient primary care visits and the number of behavioral health visits per year. Secondary outcomes were the number of mental health emergency department visits and hospitalizations per year. Results: The analytic population comprised 306 290 individuals with depression (67.4% female; mean [SD] age, 38.6 [11.9] years), 85 105 patients with bipolar disorder (59.6% female; mean [SD] age, 38.0 [11.6] years), and 71 299 patients with schizophrenia (45.1% female; mean [SD] age, 40.3 [12.2] years). After adjustment, analyses estimated a statistically significant, positive association between value-based payments and behavioral health visits for patients with depression (0.91 visits; 95% CI, 0.51-1.30) and bipolar disorder (1.01 visits; 95% CI, 0.22-1.79). There was no statistically significant changes to primary care visits for patients with depression and bipolar disorder, but value-based payments were associated with reductions in primary care visits for patients with schizophrenia (-1.31 visits; 95% CI, -2.51 to -0.12). In every diagnostic population, value-based payment was associated with significant reductions in mental health emergency department visits (population with depression: -0.01 visits [95% CI, -0.02 to -0.002]; population with bipolar disorder: -0.02 visits [95% CI, -0.05 to -0.001]; population with schizophrenia: -0.04 visits [95% CI, -0.07 to -0.01]). Conclusions and Relevance: In this cohort study, Medicaid value-based payment reform was statistically significantly associated with an increase in behavioral health visits and a reduction in mental health emergency department visits for patients with mental illness. Medicaid value-based payment may be effective at altering health care utilization in patients with mental illness.


Asunto(s)
Trastorno Depresivo Mayor , Trastornos Mentales , Estados Unidos , Humanos , Femenino , Adulto , Masculino , Estudios de Cohortes , Medicaid , Estudios Retrospectivos , Trastornos Mentales/epidemiología , Trastornos Mentales/terapia , Pacientes Ambulatorios , Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/terapia
16.
Psychophysiology ; 60(10): e14332, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37203219

RESUMEN

There remains some debate about whether beta power effects observed during sentence comprehension reflect ongoing syntactic unification operations (beta-syntax hypothesis), or instead reflect maintenance or updating of the sentence-level representation (beta-maintenance hypothesis). In this study, we used magnetoencephalography to investigate beta power neural dynamics while participants read relative clause sentences that were initially ambiguous between a subject- or an object-relative reading. An additional condition included a grammatical violation at the disambiguation point in the relative clause sentences. The beta-maintenance hypothesis predicts a decrease in beta power at the disambiguation point for unexpected (and less preferred) object-relative clause sentences and grammatical violations, as both signal a need to update the sentence-level representation. While the beta-syntax hypothesis also predicts a beta power decrease for grammatical violations due to a disruption of syntactic unification operations, it instead predicts an increase in beta power for the object-relative clause condition because syntactic unification at the point of disambiguation becomes more demanding. We observed decreased beta power for both the agreement violation and object-relative clause conditions in typical left hemisphere language regions, which provides compelling support for the beta-maintenance hypothesis. Mid-frontal theta power effects were also present for grammatical violations and object-relative clause sentences, suggesting that violations and unexpected sentence interpretations are registered as conflicts by the brain's domain-general error detection system.

17.
J Health Econ ; 90: 102770, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37216773

RESUMEN

While a large body of evidence has examined hospital concentration, its effects on health care for low-income populations are less explored. We use comprehensive discharge data from New York State to measure the effects of changes in market concentration on hospital-level inpatient Medicaid volumes. Holding fixed hospital factors constant, a one percent increase in HHI leads to a 0.6% (s.e. = 0.28%) decrease in the number of Medicaid admissions for the average hospital. The strongest effects are on admissions for birth (-1.3%, s.e. = 0.58%). These average hospital-level decreases largely reflect redistribution of Medicaid patients across hospitals, rather than overall reductions in hospitalizations for Medicaid patients. In particular, hospital concentration leads to a redistribution of admissions from non-profit hospitals to public hospitals. We find evidence that for births, physicians serving high shares of Medicaid beneficiaries in particular experience reduced admissions as concentration increased. These reductions may reflect preferences among these physicians or reduced admitting privileges by hospitals as a means to screen out Medicaid patients.


Asunto(s)
Hospitalización , Hospitales , Medicaid , Pobreza , New York , Humanos , Alta del Paciente , Hospitales/provisión & distribución , Hospitalización/estadística & datos numéricos , Modelos Estadísticos
18.
Cognition ; 226: 105148, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35533629

RESUMEN

In sentence comprehension, the parser in many languages has the option to use both the morphological form of a noun and its lexical representation when evaluating agreement. The additional step of consulting the lexicon incurs processing costs, and an important question is whether the parser takes that step even when the formal cues alone are sufficiently reliable to evaluate agreement. Our study addressed this question using electrophysiology in Zulu, a language where both grammatical gender and number features are reliably expressed formally by noun class prefixes, but only gender features are lexically specified. We observed reduced, more topographically focal LAN, and more frontally distributed alpha/beta power effects for gender compared to number agreement violations. These differences provide evidence that for gender mismatches, even though the formal cues are reliable, the parser nevertheless takes the additional step of consulting the noun's lexical representation, a step which is not available for number.


Asunto(s)
Potenciales Evocados , Lenguaje , Comprensión/fisiología , Señales (Psicología) , Electroencefalografía , Potenciales Evocados/fisiología , Humanos , Semántica
19.
J Youth Adolesc ; 40(3): 249-62, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20204687

RESUMEN

Situated within a positive psychology perspective, this study explored linkages between adolescent students' positive subjective well-being and their levels of engagement in schooling. Specifically, using structural equation modeling techniques, we evaluated the nature and directionality of longitudinal relationships between life satisfaction and student engagement variables. It was hypothesized that adolescents' life satisfaction and student engagement variables would show bidirectional relationships. To test this hypothesis, 779 students (53% female, 62% Caucasian) in a Southeastern US middle school completed a measure of global life satisfaction and measures of cognitive, emotional, and behavioral engagement at two time points, 5 months apart. A statistically significant bidirectional relationship between life satisfaction and cognitive engagement was found; however, non-significant relationships were found between life satisfaction and emotional and behavioral student engagement. The findings provide important evidence of the role of early adolescents' life satisfaction in their engagement in schooling during the important transition grades between elementary and high school. The findings also help extend the positive psychology perspective to the relatively neglected context of education.


Asunto(s)
Logro , Satisfacción Personal , Estudiantes/psicología , Adolescente , Estudios Transversales , Femenino , Felicidad , Humanos , Estudios Longitudinales , Masculino , Pruebas Psicológicas , Psicología Educacional , Calidad de Vida/psicología , Autoinforme , Sudeste de Estados Unidos
20.
Neuropsychologia ; 155: 107754, 2021 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-33476626

RESUMEN

The possibility to combine smaller units of meaning (e.g., words) to create new and more complex meanings (e.g., phrases and sentences) is a fundamental feature of human language. In the present project, we investigated how the brain supports the semantic and syntactic composition of two-word adjective-noun phrases in Dutch, using magnetoencephalography (MEG). The present investigation followed up on previous studies reporting a composition effect in the left anterior temporal lobe (LATL) when comparing neural activity at nouns combined with adjectives, as opposed to nouns in a non-compositional context. The first aim of the present study was to investigate whether this effect, as well as its modulation by noun specificity and adjective class, can also be observed in Dutch. A second aim was to investigate to what extent these effects may be driven by syntactic composition rather than primarily by semantic composition as was previously proposed. To this end, a novel condition was administered in which participants saw nouns combined with pseudowords lacking meaning but agreeing with the nouns in terms of grammatical gender, as real adjectives would. We failed to observe a composition effect or its modulation in both a confirmatory analysis (focused on the cortical region and time-window where it has previously been reported) and in exploratory analyses (where we tested multiple regions and an extended potential time-window of the effect). A syntactically driven composition effect was also not observed in our data. We do, however, successfully observe an independent, previously reported effect on single word processing in our data, confirming that our MEG data processing pipeline does meaningfully capture language processing activity by the brain. The failure to observe the composition effect in LATL is surprising given that it has been previously reported in multiple studies. Reviewing all previous studies investigating this effect, we propose that materials and a task involving imagery might be necessary for this effect to be observed. In addition, we identified substantial variability in the regions of interest analyzed in previous studies, which warrants additional checks of robustness of the effect. Further research should identify limits and conditions under which this effect can be observed. The failure to observe specifically a syntactic composition effect in such minimal phrases is less surprising given that it has not been previously reported in MEG data.


Asunto(s)
Lenguaje , Semántica , Mapeo Encefálico , Comprensión , Humanos , Magnetoencefalografía
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