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1.
Biometrics ; 80(2)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38888097

RESUMO

Convolutional neural networks (CNNs) provide flexible function approximations for a wide variety of applications when the input variables are in the form of images or spatial data. Although CNNs often outperform traditional statistical models in prediction accuracy, statistical inference, such as estimating the effects of covariates and quantifying the prediction uncertainty, is not trivial due to the highly complicated model structure and overparameterization. To address this challenge, we propose a new Bayesian approach by embedding CNNs within the generalized linear models (GLMs) framework. We use extracted nodes from the last hidden layer of CNN with Monte Carlo (MC) dropout as informative covariates in GLM. This improves accuracy in prediction and regression coefficient inference, allowing for the interpretation of coefficients and uncertainty quantification. By fitting ensemble GLMs across multiple realizations from MC dropout, we can account for uncertainties in extracting the features. We apply our methods to biological and epidemiological problems, which have both high-dimensional correlated inputs and vector covariates. Specifically, we consider malaria incidence data, brain tumor image data, and fMRI data. By extracting information from correlated inputs, the proposed method can provide an interpretable Bayesian analysis. The algorithm can be broadly applicable to image regressions or correlated data analysis by enabling accurate Bayesian inference quickly.


Assuntos
Teorema de Bayes , Neoplasias Encefálicas , Imageamento por Ressonância Magnética , Método de Monte Carlo , Redes Neurais de Computação , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética/estatística & dados numéricos , Imageamento por Ressonância Magnética/métodos , Malária/epidemiologia , Algoritmos
2.
Emerg Infect Dis ; 29(11): 2275-2284, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37877548

RESUMO

SARS-CoV-2 induces illness and death in humans by causing systemic infections. Evidence suggests that SARS-CoV-2 can induce brain pathology in humans and other hosts. In this study, we used a canine transmission model to examine histopathologic changes in the brains of dogs infected with SARS-CoV-2. We observed substantial brain pathology in SARS-CoV-2-infected dogs, particularly involving blood-brain barrier damage resembling small vessel disease, including changes in tight junction proteins, reduced laminin levels, and decreased pericyte coverage. Furthermore, we detected phosphorylated tau, a marker of neurodegenerative disease, indicating a potential link between SARS-CoV-2-associated small vessel disease and neurodegeneration. Our findings of degenerative changes in the dog brain during SARS-CoV-2 infection emphasize the potential for transmission to other hosts and induction of similar signs and symptoms. The dynamic brain changes in dogs highlight that even asymptomatic individuals infected with SARS-CoV-2 may develop neuropathologic changes in the brain.


Assuntos
COVID-19 , Doenças Neurodegenerativas , Humanos , Animais , Cães , SARS-CoV-2 , COVID-19/veterinária , Encéfalo
3.
BMC Med Ethics ; 24(1): 18, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882795

RESUMO

BACKGROUND: This study aimed to identify the healthcare providers' experience and perspectives toward end-of-life care decisions focusing on end-of-life discussion and physician's order of life-sustaining treatment documentation in Korea which are major parts of the Life-Sustaining Treatment Act. METHODS: A cross-sectional survey was conducted using a questionnaire developed by the authors. A total of 474 subjects-94 attending physicians, 87 resident physicians, and 293 nurses-participated in the survey, and the data analysis was performed in terms of frequency, percentage, mean and standard deviation using the SPSS 24.0 program. RESULTS: Study results showed that respondents were aware of terminal illness and physician's order of life-sustaining treatment in Korea well enough except for some details. Physicians reported uncertainty in terminal state diagnosis and disease trajectory as the most challenging. Study participants regarded factors (related to relationships and communications) on the healthcare providers' side as the major impediment to end-of-life discussion. Study respondents suggested that simplification of the process and more staff are required to facilitate end-of-life discussion and documentation. CONCLUSION: Based on the study results, adequate education and training for better end-of-life discussion are required for future practice. Also, a simple and clear procedure for completing a physician's order of life-sustaining treatment in Korea should be prepared and legal and ethical advice would be required. Since the enactment of the Life-Sustaining Treatment Act, several revisions already have been made including disease categories, thus continuous education to update and support clinicians is also called for.


Assuntos
Médicos , Assistência Terminal , Humanos , Estudos Transversais , Morte , República da Coreia
4.
Hum Brain Mapp ; 42(10): 3295-3304, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33939212

RESUMO

This study investigated the empathic response of postpartum women to babies in pain and the underlying neural mechanism. Postpartum women responded with more empathy and speed to babies over other stimuli compared to controls. Brain scans taken 3 months after birth showed more elevated activation in the Middle cingulate cortex/middle frontal gyrus (MCC/MFG) than the controls regardless of the task condition. When compared to the adult and neutral conditions, the posterior cingulate cortex (PCC) region was consistently more activated when postpartum women saw babies than controls. In addition, higher activation levels in the PCC region for the baby condition significantly correlated with faster and more empathic responses to babies. Considering that PCC is a core region for the theory of mind or mentalizing which requires cognitive reasoning to understand others, these results suggest that PCC might be a pivotal neural locus facilitating cognitive efforts to empathize with babies during the postpartum period. In a follow-up experiment at 12 months after birth, we were still able to observe higher activity in the MCC/MFG of postpartum women. However, previously observed PCC activation patterns disappeared 12 months after birth, despite the women's response patterns to babies still being maintained. These results suggest that the mentalizing process activated to empathize with babies in the early postpartum period becomes less cognitively demanding over time.


Assuntos
Empatia/fisiologia , Giro do Cíngulo/fisiologia , Mentalização/fisiologia , Período Pós-Parto/fisiologia , Córtex Pré-Frontal/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
5.
Am J Transplant ; 20(7): 1773-1779, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32202064

RESUMO

The COVID-19 pandemic has rapidly evolved and changed our way of life in an unprecedented manner. The emergence of COVID-19 has impacted transplantation worldwide. The impact has not been just restricted to issues pertaining to donors or recipients, but also health-care resource utilization as the intensity of cases in certain jurisdictions exceeds available capacity. Here we provide a personal viewpoint representing different jurisdictions from around the world in order to outline the impact of the current COVID-19 pandemic on organ transplantation. Based on our collective experience, we discuss mitigation strategies such as donor screening, resource planning, and a staged approach to transplant volume considerations as local resource issues demand. We also discuss issues related to transplant-related research during the pandemic, the role of transplant infectious diseases, and the influence of transplant societies for education and disseminating current information.


Assuntos
Infecções por Coronavirus/complicações , Infecções por Coronavirus/prevenção & controle , Transplante de Órgãos/tendências , Pandemias/prevenção & controle , Pneumonia Viral/complicações , Pneumonia Viral/prevenção & controle , Betacoronavirus , COVID-19 , Tomada de Decisões , Seleção do Doador , Saúde Global , Humanos , Infectologia/organização & administração , SARS-CoV-2 , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/normas , Transplantes , Populações Vulneráveis
6.
J Stroke Cerebrovasc Dis ; 29(10): 105105, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32912571

RESUMO

Heat stroke is a life-threatening disease characterized by hyperthermia and neurological dysfunction. The central nervous system is highly sensitive to hyperthermia, which causes neurological complications due to the involvement of the cerebellum, basal ganglia, anterior horn cells, and peripheral nerves. Several studies reported about clinical symptoms and brain image findings of heat stroke. Isolated cranial nerve dysfunction caused by lacunar infarction is an extremely rare condition in patient with heat stroke. We experienced a rare case of trochlear nerve palsy due to midbrain infarction caused by heat stroke.


Assuntos
Infarto Cerebral/etiologia , Golpe de Calor/complicações , Mesencéfalo/irrigação sanguínea , Acidente Vascular Cerebral Lacunar/etiologia , Doenças do Nervo Troclear/etiologia , Idoso , Aspirina/uso terapêutico , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/fisiopatologia , Fibrinolíticos/uso terapêutico , Golpe de Calor/diagnóstico , Humanos , Masculino , Recuperação de Função Fisiológica , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Acidente Vascular Cerebral Lacunar/tratamento farmacológico , Acidente Vascular Cerebral Lacunar/fisiopatologia , Resultado do Tratamento , Doenças do Nervo Troclear/diagnóstico , Doenças do Nervo Troclear/fisiopatologia
8.
Neurobiol Learn Mem ; 150: 116-135, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29544726

RESUMO

Numerous studies have suggested that postpartum women show a decline in cognitive abilities. However, to date, no study has investigated the presence of qualitative alterations in recognition memory processes in postpartum women that may lead to a decline in cognitive ability. To address this issue, we employed the Remember/Know procedure and functional magnetic resonance imaging (fMRI). Behavioral results demonstrated that compared with the matched control (CTRL) group, the postpartum (PP) group endorsed "Remember" less and "Know" more to old items. A univariate analysis of fMRI data indicated lower neural activity of the subjective recollection network in the PP group than in the CTRL group. We also performed a large-scale functional connectivity multivariate pattern analysis (fcMVPA) using task-dependent time-series to detect differences in functional connectivity patterns and neural interactivity between the PP and CTRL groups. The fcMVPA results revealed that the PP group exhibited altered functional connectivity patterns from which machine learning algorithms could discriminate group membership with 94% accuracy. Collectively, these findings demonstrated that altered subjective recollection processes in the PP group during episodic memory decisions are associated with diminished neural activity and abnormal interactivity across the subjective recollection network. We believe that this is one of the first studies demonstrating qualitative alterations in recognition memory processes in postpartum women.


Assuntos
Encéfalo/diagnóstico por imagem , Memória Episódica , Rede Nervosa/diagnóstico por imagem , Período Pós-Parto/fisiologia , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Rede Nervosa/fisiologia , Testes Neuropsicológicos , Período Pós-Parto/psicologia
9.
Genetica ; 146(2): 211-226, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29441472

RESUMO

Many peninsulas in the temperate zone played an important role as refugia of various flora and fauna, and the southern Korean Peninsula also served as a refugium for many small mammals in East Asia during the Pleistocene. The Asian lesser white-toothed shrew, Crocidura shantungensis, is a widely distributed species in East Asia, and is an appropriate model organism for exploring the role of the Korean Peninsula as a refugium of small mammals. Here, we investigated phylogenetic relationships and genetic diversity based on the entire sequence of the mitochondrial cytochrome b gene (1140 bp). A Bayesian tree for 98 haplotypes detected in 228 C. shantungensis specimens from East Asia revealed the presence of three major groups with at least 5 subgroups. Most haplotypes were distributed according to their geographic proximity. Pairwise FST's and analysis of molecular variance (AMOVA) revealed a high degree of genetic differentiation and variance among regions as well as among populations within region, implying little gene flow among local populations. Genetic evidence from South Korean islands, Jeju-do Island of South Korea, and Taiwan leads us to reject the hypothesis of recent population expansion. We observed unique island-type genetic characteristics consistent with geographic isolation and resultant genetic drift. Phylogeographic inference, together with estimates of genetic differentiation and diversity, suggest that the southern most part the Korean Peninsula, including offshore islands, played an important role as a refugium for C. shantungensis during the Pleistocene. However, the presence of several refugia on the mainland of northeast Asia is also proposed.


Assuntos
Variação Genética , Musaranhos/genética , Animais , Citocromos b/genética , Haplótipos , Coreia (Geográfico) , Filogeografia , Musaranhos/classificação
10.
Virus Genes ; 54(4): 587-590, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29691774

RESUMO

Rabbits are considered a new natural reservoir of hepatitis E virus (HEV). In this study, HEV infection was verified by the detection of partial genomic sequence of HEV and anti-HEV antibodies in specific pathogen-free (SPF) rabbits. HEV RNA was found in 6.4% serum and 13.5% fecal samples from 126 SPF rabbits. Anti-HEV antibodies were also detected in 4.0% of the SPF rabbits. HEV genetic sequences isolated from the rabbits were clustered into a rabbit HEV clade with other rabbit HEV isolates; they were found to be most closely related with a rabbit HEV sequence previously reported in Korea. Therefore, HEV infection should be diagnosed before conducting experiments involving SPF rabbits.


Assuntos
Doenças dos Animais/virologia , Vírus da Hepatite E , Hepatite E/veterinária , Doenças dos Animais/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/genética , Genótipo , Vírus da Hepatite E/classificação , Vírus da Hepatite E/genética , Vírus da Hepatite E/imunologia , Filogenia , RNA Viral , Coelhos , República da Coreia
11.
J Med Virol ; 89(11): 1995-2002, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28617964

RESUMO

Hepatitis caused by hepatitis E virus (HEV) is a public health concern worldwide. HEV strains have been isolated from several animal species, some of which induce zoonosis. Recently, the isolation of HEV from rabbits was reported. Here, the partial capsid gene (320 bp) of HEV was detected in rabbit feces via reverse transcriptase-polymerase chain reaction (RT-PCR). Rabbit HEV was found in two of six rabbit farms and 17 of 264 rabbit fecal samples (6.4%). A phylogenetic analysis of the partial capsid gene classified the 17 HEV isolates into the putative rabbit HEV clade. A full genomic sequence, KOR-Rb-1, was obtained from one rabbit HEV isolate by 5' and 3' rapid amplification of cDNA ends-PCR and RT-PCR, and comprised 7275 bp excluding the 3' poly(A) tail. It shared 77.5-86.8%, 86.6%, and 80.2-84.3% nucleotide identities with rabbit HEV isolates from China, the US, and France, respectively. It also shared 72.3-73.0%, 71.4%, 76.7-78.3%, 72.8-73.3%, and 47.1-47.2% nucleotide identities with representative strains of HEV-1, HEV-2, HEV-3, HEV-4, and avian HEV, respectively. A full-genome phylogenetic analysis classified KOR-Rb-1 into the provisional rabbit HEV clade. This isolate could be used to study the pathogenesis and zoonotic potential of rabbit HEV.


Assuntos
Vírus da Hepatite E/genética , Hepatite E/veterinária , Coelhos/virologia , Animais , Proteínas do Capsídeo/genética , China/epidemiologia , Fezes/virologia , França/epidemiologia , Genoma Viral , Genótipo , Hepatite E/epidemiologia , Hepatite E/transmissão , Hepatite E/virologia , Vírus da Hepatite E/classificação , Vírus da Hepatite E/isolamento & purificação , Humanos , Filogenia , Prevalência , RNA Viral , Reação em Cadeia da Polimerase em Tempo Real , República da Coreia/epidemiologia , Análise de Sequência de DNA , Estados Unidos/epidemiologia , Zoonoses
12.
Opt Express ; 24(3): 2065-71, 2016 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-26906781

RESUMO

We investigate field enhancement inside metal-insulator-metal gaps with asymmetric thicknesses and tapered shapes in the terahertz regime. Finite-difference time-domain simulations were conducted for calculation of field enhancement factor. The calculation indicates that for asymmetric sample, field enhancement increases proportionally with the decrease of the thinner of the two metal film thicknesses surrounding the gap. Concomitantly, angle variation has little effect on the field enhancement if the thickness of the narrowest gap region is fixed. A model based on the capacitor concept is proposed for intuitive understanding of the phenomena.

13.
PLoS Genet ; 9(7): e1003554, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23874208

RESUMO

We previously established an 80 kb haplotype upstream of TNFSF4 as a susceptibility locus in the autoimmune disease SLE. SLE-associated alleles at this locus are associated with inflammatory disorders, including atherosclerosis and ischaemic stroke. In Europeans, the TNFSF4 causal variants have remained elusive due to strong linkage disequilibrium exhibited by alleles spanning the region. Using a trans-ancestral approach to fine-map the locus, utilising 17,900 SLE and control subjects including Amerindian/Hispanics (1348 cases, 717 controls), African-Americans (AA) (1529, 2048) and better powered cohorts of Europeans and East Asians, we find strong association of risk alleles in all ethnicities; the AA association replicates in African-American Gullah (152,122). The best evidence of association comes from two adjacent markers: rs2205960-T (P=1.71 × 10(-34) , OR=1.43[1.26-1.60]) and rs1234317-T (P=1.16 × 10(-28) , OR=1.38[1.24-1.54]). Inference of fine-scale recombination rates for all populations tested finds the 80 kb risk and non-risk haplotypes in all except African-Americans. In this population the decay of recombination equates to an 11 kb risk haplotype, anchored in the 5' region proximal to TNFSF4 and tagged by rs2205960-T after 1000 Genomes phase 1 (v3) imputation. Conditional regression analyses delineate the 5' risk signal to rs2205960-T and the independent non-risk signal to rs1234314-C. Our case-only and SLE-control cohorts demonstrate robust association of rs2205960-T with autoantibody production. The rs2205960-T is predicted to form part of a decameric motif which binds NF-κBp65 with increased affinity compared to rs2205960-G. ChIP-seq data also indicate NF-κB interaction with the DNA sequence at this position in LCL cells. Our research suggests association of rs2205960-T with SLE across multiple groups and an independent non-risk signal at rs1234314-C. rs2205960-T is associated with autoantibody production and lymphopenia. Our data confirm a global signal at TNFSF4 and a role for the expressed product at multiple stages of lymphocyte dysregulation during SLE pathogenesis. We confirm the validity of trans-ancestral mapping in a complex trait.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Lúpus Eritematoso Sistêmico/genética , Ligante OX40/genética , Negro ou Afro-Americano/genética , Alelos , Povo Asiático/genética , Mapeamento Cromossômico , Feminino , Genótipo , Haplótipos , Hispânico ou Latino/genética , Humanos , Desequilíbrio de Ligação , Lúpus Eritematoso Sistêmico/patologia , Linfócitos/patologia , Masculino , NF-kappa B/genética , Polimorfismo de Nucleotídeo Único , População Branca/genética
14.
J Korean Med Sci ; 31(7): 1089-93, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27366007

RESUMO

Kidney length is the most useful parameter for clinical measurement of kidney size, and is useful to distinguish acute kidney injury from chronic kidney disease. In this prospective observational study of 437 normal children aged between 0 and < 13 years, kidney length was measured using sonography. There were good correlations between kidney length and somatic values, including age, weight, height, and body surface area. The rapid growth of height during the first 2 years of life was intimately associated with a similar increase in kidney length, suggesting that height should be considered an important factor correlating with kidney length. Based on our findings, the following regression equation for the reference values of bilateral kidney length for Korean children was obtained: kidney length of the right kidney (cm) = 0.051 × height (cm) + 2.102; kidney length of the left kidney (cm) = 0.051 × height (cm) + 2.280. This equation may aid in the diagnosis of various kidney disorders.


Assuntos
Rim/diagnóstico por imagem , Fatores Etários , Povo Asiático , Estatura , Superfície Corporal , Peso Corporal , Criança , Pré-Escolar , Feminino , Gráficos de Crescimento , Humanos , Lactente , Recém-Nascido , Nefropatias/diagnóstico , Masculino , Estudos Prospectivos , Valores de Referência , República da Coreia , Ultrassonografia
15.
Nano Lett ; 15(10): 6318-23, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26352780

RESUMO

We report that vanadium dioxide films patterned with λ/100000 nanogaps exhibit an anomalous transition behavior at millimeter wavelengths. Most of the hybrid structure's switching actions occur well below the insulator to metal transition temperature, starting from 25 °C, so that the hysteresis curves completely separate themselves from their bare film counterparts. It is found that thermally excited intrinsic carriers are responsible for this behavior by introducing enough loss in the context of the radically modified electromagnetic environment in the vicinity of the nanogaps. This phenomenon newly extends the versatility of insulator to metal transition devices to encompass their semiconductor properties.

16.
Nano Lett ; 15(9): 5893-8, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26301339

RESUMO

We demonstrate that high-field terahertz (THz) pulses trigger transient insulator-to-metal transition in a nanoantenna patterned vanadium dioxide thin film. THz transmission of vanadium dioxide instantaneously decreases in the presence of strong THz fields. The transient THz absorption indicates that strong THz fields induce electronic insulator-to-metal transition without causing a structural transformation. The transient phase transition is activated on the subcycle time scale during which the THz pulse drives the electron distribution of vanadium dioxide far from equilibrium and disturb the electron correlation. The strong THz fields lower the activation energy in the insulating phase. The THz-triggered insulator-to-metal transition gives rise to hysteresis loop narrowing, while lowering the transition temperature both for heating and cooling sequences. THz nanoantennas enhance the field-induced phase transition by intensifying the field strength and improve the detection sensitivity via antenna resonance. The experimental results demonstrate a potential that plasmonic nanostructures incorporating vanadium dioxide can be the basis for ultrafast, energy-efficient electronic and photonic devices.

17.
Opt Express ; 23(11): 14937-45, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26072850

RESUMO

We present a new and versatile technique of self-assembly lithography to fabricate a large scale Cadmium selenide quantum dots-silver nanogap metamaterials. After optical and electron microscopic characterizations of the metamaterials, we performed spatially resolved photoluminescence transmission measurements. We obtained highly quenched photoluminescence spectra compared to those from bare quantum dots film. We then quantified the quenching in terms of an average photoluminescence enhancement factor. A finite difference time domain simulation was performed to understand the role of an electric field enhancement in the nanogap over this quenching. Finally, we interpreted the mechanism of the photoluminescence quenching and proposed fabrication method of new metamaterials using our technique.

18.
Phys Rev Lett ; 115(12): 125501, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26431000

RESUMO

Metal-graphene-metal hybrid structures allow angstrom-scale van der Waals gaps, across which electron tunneling occurs. We squeeze terahertz electromagnetic waves through these λ/10 000 000 gaps, accompanied by giant field enhancements. Unprecedented transmission reduction of 97% is achieved with the transient voltage across the gap saturating at 5 V. Electron tunneling facilitated by the transient electric field strongly modifies the gap index, starting a self-limiting process related to the barrier height. Our work enables greater interplay between classical optics and quantum tunneling, and provides optical indices to the van der Waals gaps.

19.
J Cogn Neurosci ; 26(4): 810-24, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24168218

RESUMO

It has been proposed that choice utility exhibits an inverted U-shape as a function of the number of options in the choice set. However, most researchers have so far only focused on the "physically extant" number of options in the set while disregarding the more important psychological factor, the "subjective" number of options worth considering to choose-that is, the size of the consideration set. To explore this previously ignored aspect, we examined how variations in the size of a consideration set can produce different affective consequences after making choices and investigated the underlying neural mechanism using fMRI. After rating their preferences for art posters, participants made a choice from a presented set and then reported on their level of satisfaction with their choice and the level of difficulty experienced in choosing it. Our behavioral results demonstrated that enlarged assortment set can lead to greater choice satisfaction only when increases in both consideration set size and preference contrast are involved. Moreover, choice difficulty is determined based on the size of an individual's consideration set rather than on the size of the assortment set, and it decreases linearly as a function of the level of contrast among alternatives. The neuroimaging analysis of choice-making revealed that subjective consideration set size was encoded in the striatum, the dACC, and the insula. In addition, the striatum also represented variations in choice satisfaction resulting from alterations in the size of consideration sets, whereas a common neural specificity for choice difficulty and consideration set size was shown in the dACC. These results have theoretical and practical importance in that it is one of the first studies investigating the influence of the psychological attributes of choice sets on the value-based decision-making process.


Assuntos
Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Mapeamento Encefálico , Emoções , Feminino , Giro do Cíngulo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Análise e Desempenho de Tarefas , Percepção Visual
20.
Brain Cogn ; 88: 55-64, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24859091

RESUMO

Accurate person perception is crucial in social decision-making. One of the central elements in successful social perception is the ability to understand another's response bias; this is because the same behavior can represent different inner states depending on whether other people are yea-sayers or naysayers. In the present study, we have tried to investigate how the internal biases of others are perceived. Using a multi-trial learning paradigm, perceivers made predictions about a target's responses to various suggested activities and then received feedback for each prediction trial-by-trial. Our hypotheses were that (1) the internal decision criterion of the targets would be realized through repeated experiences, and (2) due to positive-negative asymmetry, yea-sayers would be recognized more gradually than naysayers through the probabilistic integration of repeated experiences. To find neural evidence that tracks probabilistic integration when forming person knowledge on response biases, we employed a model-based fMRI with a State-Space Model. We discovered that person knowledge about yea-sayers modulated several brain regions, including caudate nucleus, DLPFC, hippocampus, etc. Moreover, when person knowledge was updated with incorrect performance feedback, brain regions including the caudate nucleus, DLPFC, dmPFC, and TPJ were also involved. There were overlapping regions for both processes, caudate nucleus and DLPFC, suggesting that these regions take crucial roles in forming person knowledge with repeated feedback, while reflecting acquired information up to the current prediction.


Assuntos
Encéfalo/fisiologia , Percepção Social , Adulto , Mapeamento Encefálico , Tomada de Decisões/fisiologia , Retroalimentação Psicológica/fisiologia , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa , Comportamento Social , Adulto Jovem
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