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1.
Hum Brain Mapp ; 43(10): 3195-3206, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35344245

RESUMO

Recent research suggests there is a neural organization for representing abstract concepts that is common across English speakers. To investigate the possible role of language on the representation of abstract concepts, multivariate pattern analytic (MVPA) techniques were applied to fMRI data to compare the neural representations of 28 individual abstract concepts between native English and Mandarin speakers. Factor analyses of the activation patterns of the 28 abstract concepts from both languages characterized this commonality in terms of a set of four underlying neurosemantic dimensions, indicating the degree to which a concept is verbally represented, internal to the person, contains social content, and is rule-based. These common semantic dimensions (factors) underlying the 28 concepts provided a sufficient basis for reliably identifying the individual abstract concepts from their neural signature in the other language with a mean rank accuracy of 0.65 (p < .001). Although the neural dimensions used for representing abstract concepts are common across languages, differences in the meaning of some individual concepts can be accommodated in terms of differential salience of particular dimensions. These semantic dimensions constitute a set of neurocognitive resources for abstract concept representations within a larger set of regions responsible for general semantic processing.


Assuntos
Formação de Conceito , Idioma , Mapeamento Encefálico/métodos , Formação de Conceito/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Semântica
2.
Cereb Cortex ; 30(4): 2157-2166, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-31665238

RESUMO

The abstractness of concepts is sometimes defined indirectly as lacking concreteness, this view provides little insight into their cognitive or neural basis. Multivariate pattern analytic techniques applied to functional magnetic resonance imaging data were used to characterize the neural representations of 28 individual abstract concepts. A classifier trained on the concepts' neural signatures reliably decoded their neural representations in an independent subset of data for each participant. There was considerable commonality of the neural representations across participants as indicated by the accurate classification of each participant's concepts based on the neural signatures obtained in other participants. Group-level factor analysis revealed 3 semantic dimensions underlying the 28 concepts, suggesting a brain-based ontology for this set of abstract concepts. The 3 dimensions corresponded to 1) the degree a concept was Verbally Represented; 2) whether a concept was External (or Internal) to the individual, and 3) whether the concept contained Social Content. Further exploration of the Verbal Representation dimension suggests that the degree a concept is verbally represented can be construed as a point on a continuum between language faculties and perceptual faculties. A predictive model, based on independent behavioral ratings of the 28 concepts along the 3 factor dimensions, provided converging evidence for the interpretations.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Formação de Conceito/fisiologia , Imageamento por Ressonância Magnética/métodos , Leitura , Semântica , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
3.
Front Pharmacol ; 10: 1312, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31787896

RESUMO

Prenatal ethanol exposure (PAE) induces behavioral maladptations in offspring, including a deficit in memory formation which is part of the umbrella sign of fetal alcohol spectrum disorder. Clinical and preclinical studies have shown that iron depletion exacerbates cognitive problems in offspring exposed to ethanol in utero and that PAE promotes dysregulation in brain iron homeostasis. However, the mechanisms underlying brain iron dysregulation and neuronal activity defects in adolescent offspring of PAE are unclear and poorly understand. Here, we used a PAE rat model to analyze messenger RNA (mRNA) and protein expression of iron homeostasis genes such as transferrin receptor (TfR), divalent metal transporter (DMT1), ferroportin (FPN1), and ferritin (FT) in brain areas associated with memory formation such as the prefrontal cortex (PFC), ventral tegmental area, and hippocampus. Interestingly, we found that 21 day old PAE rats have higher mRNA expression of DMT1 in the PFC, and TfR in the hippocampus, compared to control animals. In contrast FPN has lower mRNA expression in the PFC, and FT and FPN1 have lower expression in the hippocampus. In agreement with these results, we found a 1.5-2 fold increase of TfR and DMT1 protein levels both in the hippocampus and the PFC. Additionally, using an electrophysiological approach, we found that in hippocampal slices from PAE rats, iron treatment decreased long-term potentiation (LTP), but not AMPAR basal transmission (AMPAR fEPSP). In contrast, in control slices Fe-NTA did not affect LTP but decreased significantly the AMPAR fEPSP. Meanwhile, iron chelation with deferiprone decreased AMPAR transmission in PAE and control slices and decreased LTP only in controls slices. These results suggest that PAE affects iron homeostasis of specific brain areas-PFC and hippocampus-which could be involved in maladaptive cognition observed in this animal model.

4.
Am J Community Psychol ; 62(1-2): 87-100, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30071136

RESUMO

Relative to their peers, Latino youth are underinvolved in organized community activities (e.g., Boys and Girls Club), and their experiences lack examination. This study employed a neighborhood case-study approach to examine the experiences of Latino youth in a neighborhood with high levels of violence and their participation in organized community activities. Employing a cluster sampling design (Lohr, Sampling: Design and analysis. Pacific Grove, CA: Nelson Education, 2009), we used quantitative, spatial, and qualitative data to understand adolescents' participation in organized community activities. Furthermore, to understand how adolescents from the same neighborhood may experience violence differently we examined gender differences. Those who participated in organized community activities witnessed more violence, regardless of gender. General violence (e.g., robberies, shootings) was dispersed throughout the neighborhood, but gender-specific violence was concentrated along the main street of the neighborhood. In qualitative interviews, adolescents reported this concentration of violence a deterrent to their participation: sexual harassment for girls and gang intimidation for boys. Our findings highlight the unique experiences of youth in violent neighborhoods and the importance of examining differential constraints for those within the same neighborhood.


Assuntos
Participação da Comunidade , Hispânico ou Latino/psicologia , Características de Residência , Violência/psicologia , Adolescente , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Meio-Oeste dos Estados Unidos , Fatores Sexuais , Violência/estatística & dados numéricos , Adulto Jovem
5.
Cogn Neuropsychol ; 33(3-4): 257-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27314175

RESUMO

The generativity and complexity of human thought stem in large part from the ability to represent relations among concepts and form propositions. The current study reveals how a given object such as rabbit is neurally encoded differently and identifiably depending on whether it is an agent ("the rabbit punches the monkey") or a patient ("the monkey punches the rabbit"). Machine-learning classifiers were trained on functional magnetic resonance imaging (fMRI) data evoked by a set of short videos that conveyed agent-verb-patient propositions. When tested on a held-out video, the classifiers were able to reliably identify the thematic role of an object from its associated fMRI activation pattern. Moreover, when trained on one subset of the study participants, classifiers reliably identified the thematic roles in the data of a left-out participant (mean accuracy = .66), indicating that the neural representations of thematic roles were common across individuals.


Assuntos
Mapeamento Encefálico/estatística & dados numéricos , Formação de Conceito/fisiologia , Idioma , Aprendizado de Máquina/estatística & dados numéricos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Pensamento/fisiologia , Humanos
6.
Soc Sci Med ; 165: 263-270, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26806315

RESUMO

Health navigators are a new health care workforce created by the Affordable Care Act (ACA) to assist low-income minority populations with acquiring health insurance. Given the high levels of distrust among the poor toward government and the medical profession, this article asks: How do health navigators build the legitimacy necessary to persuade low-income uninsured clients to enroll in health insurance? Through ethnography of face-to-face interaction between navigators and the uninsured poor in Chicago, this study shows that successful navigators deployed a combination of cultural repertoires for building trust and legitimacy. These repertoires included ceding control of the conversation, creating ethnic solidarity, and disassociating themselves from government bureaucrats or self-serving insurance employees. These findings demonstrate the usefulness of cultural sociology for understanding health insurance provision to the poor, ACA outreach efforts, and the more general study of how occupations legitimize themselves to clients.


Assuntos
Pessoas sem Cobertura de Seguro de Saúde/estatística & dados numéricos , Navegação de Pacientes/métodos , Patient Protection and Affordable Care Act/tendências , Pobreza/estatística & dados numéricos , Adulto , Chicago , Feminino , Humanos , Cobertura do Seguro/normas , Cobertura do Seguro/estatística & dados numéricos , Masculino , Patient Protection and Affordable Care Act/organização & administração , Pesquisa Qualitativa
7.
Brain Lang ; 132: 7-13, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24681401

RESUMO

Voice control is critical to communication. To date, studies have used behavioral, electrophysiological and functional data to investigate the neural correlates of voice control using perturbation tasks, but have yet to examine the interactions of these neural regions. The goal of this study was to use structural equation modeling of functional neuroimaging data to examine network properties of voice with and without perturbation. Results showed that the presence of a pitch shift, which was processed as an error in vocalization, altered connections between right STG and left STG. Other regions that revealed differences in connectivity during error detection and correction included bilateral inferior frontal gyrus, and the primary and pre motor cortices. Results indicated that STG plays a critical role in voice control, specifically, during error detection and correction. Additionally, pitch perturbation elicits changes in the voice network that suggest the right hemisphere is critical to pitch modulation.


Assuntos
Córtex Cerebral/fisiologia , Retroalimentação Fisiológica/fisiologia , Modelos Neurológicos , Discriminação da Altura Tonal/fisiologia , Voz/fisiologia , Adulto , Mapeamento Encefálico/métodos , Neuroimagem Funcional/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Córtex Motor/fisiologia , Rede Nervosa/fisiologia , Percepção da Altura Sonora/fisiologia , Córtex Pré-Frontal/fisiologia , Lobo Temporal/fisiologia
8.
J Pain ; 13(6): 532-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22537559

RESUMO

UNLABELLED: Recently, the lexicon of pain was refined into a parsimonious set of words making up the Pain Descriptor System (PDS). The present study investigated the latent structure of the sensory category of the PDS with its 24 descriptors distributed equally across 8 subcategories. A sample of 629 chronic pain patients rated the degree to which each of these words described their pain. It was found that coldness-related words were rarely used and shared high covariance with other descriptors, thus warranting their removal as a subcategory. Confirmatory factor analysis of a previously theorized single higher-order model of 7 latent factors (each with 3 observed variables) resulted in poor fit, x(2)(181) = 377.72, P < .05; comparative fit index (CFI) = .915; root mean square error of approximation (RMSEA) = .04. This model was replaced with a dual higher-order model retaining the same 7 latent factors plus 2 higher-order factors corresponding to deep pain versus superficial pain. This model provided a good representation of the data, x(2)(181) = 301.07, P < .05; CFI = .948; RMSEA = .032. Therefore, descriptors of pain sensation differentiate sensory quality while also reflecting a fundamental dichotomy supported by neurophysiological research. Thus, the lexicon can illuminate pathophysiology, thereby clarifying pain diagnoses. PERSPECTIVE: Confirmatory factor analysis was performed on pain sensation descriptors used by 629 patients. This supported a hierarchical model with 7 lower-order factors plus 2 higher-order factors corresponding to deep pain versus superficial pain. By reflecting neurophysiology, this lexicon of pain can offer diagnostic clues.


Assuntos
Idioma , Medição da Dor/métodos , Dor/diagnóstico , Terminologia como Assunto , Análise Fatorial , Humanos
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