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1.
Soc Cogn Affect Neurosci ; 16(9): 903-914, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-33760100

RESUMO

Roughly 20 years of functional magnetic resonance imaging (fMRI) studies have investigated the neural correlates underlying engagement in social cognition (e.g. empathy and emotion perception) about targets spanning various social categories (e.g. race and gender). Yet, findings from individual studies remain mixed. In the present quantitative functional neuroimaging meta-analysis, we summarized across 50 fMRI studies of social cognition to identify consistent differences in neural activation as a function of whether the target of social cognition was an in-group or out-group member. We investigated if such differences varied according to a specific social category (i.e. race) and specific social cognitive processes (i.e. empathy and emotion perception). We found that social cognition about in-group members was more reliably related to activity in brain regions associated with mentalizing (e.g. dorsomedial prefrontal cortex), whereas social cognition about out-group members was more reliably related to activity in regions associated with exogenous attention and salience (e.g. anterior insula). These findings replicated for studies specifically focused on the social category of race, and we further found intergroup differences in neural activation during empathy and emotion perception tasks. These results help shed light on the neural mechanisms underlying social cognition across group lines.


Assuntos
Imageamento por Ressonância Magnética , Cognição Social , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Cognição , Humanos , Córtex Pré-Frontal
2.
Affect Sci ; 1(3): 128-154, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36043210

RESUMO

We report the first functional neuroimaging meta-analysis on age-related differences in adult neural activity during affect. We identified and coded experimental contrasts from 27 studies (published 1997-2018) with 490 older adults (55-87 years, M age = 69 years) and 470 younger adults (18-39 years, M age = 24 years). Using multilevel kernel density analysis, we assessed functional brain activation contrasts for older vs. younger adult affect across in-scanner tasks (i.e., affect induction and perception). Relative to older adults, younger adults showed more reliable activation in subcortical structures (e.g., amygdala, thalamus, caudate) and in relatively more posterior aspects of specific brain structures (e.g., posterior insula, mid- and posterior cingulate). In contrast, older adults exhibited more reliable activation in the prefrontal cortex and more anterior aspects of specific brain structures (e.g., anterior insula, anterior cingulate). Meta-analytic coactivation network analyses further revealed that in younger adults, the amygdala and mid-cingulate were more central, locally efficient network nodes, whereas in older adults, regions in the superior and medial prefrontal cortex were more central, locally efficient network nodes. Collectively, these findings help characterize age differences in the brain basis of affect and provide insights for future investigations into the neural mechanisms underlying affective aging.

3.
J Med Ethics ; 45(11): 751-754, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31506293

RESUMO

The shortage of organs for transplantation by its nature prompts ethical dilemmas. For example, although there is an imperative to save human life and reduce suffering by maximising the supply of vital organs, there is an equally important obligation to ensure that the process by which we increase the supply respects the rights of all stakeholders. In a relatively unexamined practice in the USA, organs are procured from unrepresented decedents without their express consent. Unrepresented decedents have no known healthcare wishes or advance care planning document; they also lack a surrogate. The Revised Uniform Anatomical Gift Act (RUAGA) of 2006 sends a mixed message about the procurement of organs from this patient population and there are hospitals that authorise donation. In addition, in adopting the RUAGA, some states included provisions that clearly allow organ procurement from unrepresented decedents. An important unanswered question is whether this practice meets the canons of ethical permissibility. The current Brief Report presents two principled approaches to the topic as a way of highlighting some of the complexities involved. Concluding remarks offer suggestions for future research and discussion.


Assuntos
Obtenção de Tecidos e Órgãos/ética , Obtenção de Tecidos e Órgãos/métodos , Humanos , Consentimento Livre e Esclarecido/ética , Consentimento Livre e Esclarecido/legislação & jurisprudência , Consentimento do Representante Legal/ética , Consentimento do Representante Legal/legislação & jurisprudência
4.
Proc Natl Acad Sci U S A ; 116(30): 15033-15041, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31289235

RESUMO

Flying birds maneuver effectively through lateral gusts, even when gust speeds are as high as flight speeds. What information birds use to sense gusts and how they compensate is largely unknown. We found that lovebirds can maneuver through 45° lateral gusts similarly well in forest-, lake-, and cave-like visual environments. Despite being diurnal and raised in captivity, the birds fly to their goal perch with only a dim point light source as a beacon, showing that they do not need optic flow or a visual horizon to maneuver. To accomplish this feat, lovebirds primarily yaw their bodies into the gust while fixating their head on the goal using neck angles of up to 30°. Our corroborated model for proportional yaw reorientation and speed control shows how lovebirds can compensate for lateral gusts informed by muscle proprioceptive cues from neck twist. The neck muscles not only stabilize the lovebirds' visual and inertial head orientations by compensating low-frequency body maneuvers, but also attenuate faster 3D wingbeat-induced perturbations. This head stabilization enables the vestibular system to sense the direction of gravity. Apparently, the visual horizon can be replaced by a gravitational horizon to inform the observed horizontal gust compensation maneuvers in the dark. Our scaling analysis shows how this minimal sensorimotor solution scales favorably for bigger birds, offering local wind angle feedback within a wingbeat. The way lovebirds glean wind orientation may thus inform minimal control algorithms that enable aerial robots to maneuver in similar windy and dark environments.


Assuntos
Agapornis/fisiologia , Retroalimentação Sensorial/fisiologia , Voo Animal/fisiologia , Orientação/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Animais , Escuridão , Feminino , Masculino , Músculos do Pescoço/fisiologia , Percepção Visual/fisiologia , Vento , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia
5.
Menopause ; 25(2): 242, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29206772
8.
Clin Auton Res ; 20(2): 105-11, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19633908

RESUMO

BACKGROUND: Vasovagal response (VVR) is provoked by a reduced venous blood return to the heart as a reaction to orthostatic stress and to haemorrhage. Recently, two cases were reported showing elevated plasma concentration of von-Willebrand-factor (VWF) and factor VIII (FVIII) after VVR due to venapuncture. Although the effect of epinephrine as trigger for VWF liberation is known, a connection between VVR and activation of the coagulation system has not been studied systematically. METHODS: We examined 21 subjects with lower body negative pressure. We measured the plasma concentration of von-Willebrand-factor-antigen (VWF:Ag), the activity of von-Willebrand-factor-Ristocetin-Cofactor (VWF:RiCo) and FVIII at several stress-levels and consecutively split up the different VWF-multimers. RESULTS: In 16 of 21 subjects VVR could be induced. These subjects showed a significant increase of VWF:Ag concentration in plasma and an increase of FVIII and VWF:RiCo activity. The five individuals who experienced all stress-levels without VVR did not show any changes in their clotting factor levels. CONCLUSION: VVR leads to measurable changes in the coagulation system. This might be a further diagnostic tool in treating patients with syncope.


Assuntos
Coagulação Sanguínea/fisiologia , Nervo Vago/fisiologia , Vasodilatação/fisiologia , Adolescente , Adulto , Fator VIII/metabolismo , Feminino , Humanos , Pressão Negativa da Região Corporal Inferior , Masculino , Adulto Jovem , Fator de von Willebrand/imunologia , Fator de von Willebrand/metabolismo
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