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1.
Trends Cogn Sci ; 27(5): 456-467, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36941184

RESUMO

Learning about threats is crucial for survival and fundamentally rests upon Pavlovian conditioning. However, Pavlovian threat learning is largely limited to detecting known (or similar) threats and involves first-hand exposure to danger, which inevitably poses a risk of harm. We discuss how individuals leverage a rich repertoire of mnemonic processes that operate largely in safety and significantly expand our ability to recognize danger beyond Pavlovian threat associations. These processes result in complementary memories - acquired individually or through social interactions - that represent potential threats and the relational structure of our environment. The interplay between these memories allows danger to be inferred rather than directly learned, thereby flexibly protecting us from potential harm in novel situations despite minimal prior aversive experience.


Assuntos
Condicionamento Clássico , Aprendizagem , Humanos , Memória , Afeto
2.
Nature ; 582(7810): 84-88, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32483374

RESUMO

Data analysis workflows in many scientific domains have become increasingly complex and flexible. Here we assess the effect of this flexibility on the results of functional magnetic resonance imaging by asking 70 independent teams to analyse the same dataset, testing the same 9 ex-ante hypotheses1. The flexibility of analytical approaches is exemplified by the fact that no two teams chose identical workflows to analyse the data. This flexibility resulted in sizeable variation in the results of hypothesis tests, even for teams whose statistical maps were highly correlated at intermediate stages of the analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Notably, a meta-analytical approach that aggregated information across teams yielded a significant consensus in activated regions. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset2-5. Our findings show that analytical flexibility can have substantial effects on scientific conclusions, and identify factors that may be related to variability in the analysis of functional magnetic resonance imaging. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for performing and reporting multiple analyses of the same data. Potential approaches that could be used to mitigate issues related to analytical variability are discussed.


Assuntos
Análise de Dados , Ciência de Dados/métodos , Ciência de Dados/normas , Conjuntos de Dados como Assunto , Neuroimagem Funcional , Imageamento por Ressonância Magnética , Pesquisadores/organização & administração , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Conjuntos de Dados como Assunto/estatística & dados numéricos , Feminino , Humanos , Modelos Logísticos , Masculino , Metanálise como Assunto , Modelos Neurológicos , Reprodutibilidade dos Testes , Pesquisadores/normas , Software
3.
Neuroimage ; 199: 680-690, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31173902

RESUMO

Acute stress triggers a broad psychophysiological response that is adaptive if rapidly activated and terminated. While the brain controls the stress response, it is strongly affected by it. Previous research of stress effects on brain activation and connectivity has mainly focused on pre-defined brain regions or networks, potentially missing changes in the rest of the brain. We here investigated how both stress reactivity and stress recovery are reflected in whole-brain network topology and how changes in functional connectivity relate to other stress measures. Healthy young males (n = 67) completed the Trier Social Stress Test or a control task. From 60 min before until 105 min after stress onset, blocks of resting-state fMRI were acquired. Subjective, autonomic, and endocrine measures of the stress response were assessed throughout the experiment. Whole-brain network topology was quantified using Eigenvector centrality (EC) mapping, which detects central hubs of a network. Stress influenced subjective affect, autonomic activity, and endocrine measures. EC differences between groups as well as before and after stress exposure were found in the thalamus, due to widespread connectivity changes in the brain. Stress-driven EC increases in the thalamus were significantly correlated with subjective stress ratings and showed non-significant trends for a correlation with heart rate variability and saliva cortisol. Furthermore, increases in thalamic EC and in saliva cortisol persisted until 105 min after stress onset. We conclude that thalamic areas are central for information processing after stress exposure and may provide an interface for the stress response in the rest of the body and in the mind.


Assuntos
Córtex Cerebral/fisiopatologia , Conectoma , Rede Nervosa/fisiopatologia , Estresse Psicológico/fisiopatologia , Tálamo/fisiopatologia , Adolescente , Adulto , Sistema Nervoso Autônomo/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Humanos , Hidrocortisona/metabolismo , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Estresse Psicológico/diagnóstico por imagem , Estresse Psicológico/metabolismo , Tálamo/diagnóstico por imagem , Adulto Jovem
4.
Sci Data ; 6: 180307, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30747913

RESUMO

The dataset enables exploration of higher-order cognitive faculties, self-generated mental experience, and personality features in relation to the intrinsic functional architecture of the brain. We provide multimodal magnetic resonance imaging (MRI) data and a broad set of state and trait phenotypic assessments: mind-wandering, personality traits, and cognitive abilities. Specifically, 194 healthy participants (between 20 and 75 years of age) filled out 31 questionnaires, performed 7 tasks, and reported 4 probes of in-scanner mind-wandering. The scanning session included four 15.5-min resting-state functional MRI runs using a multiband EPI sequence and a hig h-resolution structural scan using a 3D MP2RAGE sequence. This dataset constitutes one part of the MPI-Leipzig Mind-Brain-Body database.


Assuntos
Cognição , Conectoma , Personalidade , Atenção , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Brain Struct Funct ; 224(2): 925-935, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30547311

RESUMO

Cortical connectivity conforms to a series of organizing principles that are common across species. Spatial proximity, similar cortical type, and similar connectional profile all constitute factors for determining the connectivity between cortical regions. We previously demonstrated another principle of connectivity that is closely related to the spatial layout of the cerebral cortex. Using functional connectivity from resting-state fMRI in the human cortex, we found that the further a region is located from primary cortex, the more distant are its functional connections with the other areas of the cortex. However, it remains unknown whether this relationship between cortical layout and connectivity extends to other primate species. Here, we investigated this relationship using both resting-state functional connectivity as well as gold-standard tract-tracing connectivity in the macaque monkey cortex. For both measures of connectivity, we found a gradient of connectivity distance extending between primary and frontoparietal regions. In the human cortex, the further a region is located from primary areas, the stronger its connections to distant portions of the cortex, with connectivity distance highest in frontal and parietal regions. The similarity between the human and macaque findings provides evidence for a phylogenetically conserved relationship between the spatial layout of cortical areas and connectivity.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Animais , Mapeamento Encefálico , Macaca mulatta , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem
6.
Emotion ; 17(8): 1156-1165, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28358561

RESUMO

The literature concerning biological influences on positive social behavior shows that, in nonthreatening contexts, tonic oxytocin (OT) and respiratory sinus arrhythmia (RSA) each predict positive, affiliative behaviors toward certain others and are associated with positive health outcomes. The purpose of this investigation was to determine the degree to which the positive affiliative correlates of OT and RSA can be distinguished when observed at the level of everyday life events. A sample of midlife adults (N = 73) provided tonic indices of these biological characteristics, as well as perceptions of a variety of common life events alongside reports of their emotions during those events. OT and RSA each independently moderated the link between perceived event sociality and positive emotions, whereas only RSA predicted the probability of being with other people during an event. These findings suggest that OT and RSA may each be linked to positive social experiences in complementary yet distinct ways. (PsycINFO Database Record


Assuntos
Emoções , Ocitocina/metabolismo , Arritmia Sinusal Respiratória/fisiologia , Comportamento Social , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Neuroimage ; 153: 168-178, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28300639

RESUMO

We evaluated whether sliding-window analysis can reveal functionally relevant brain network dynamics during a well-established fear conditioning paradigm. To this end, we tested if fMRI fluctuations in amygdala functional connectivity (FC) can be related to task-induced changes in physiological arousal and vigilance, as reflected in the skin conductance level (SCL). Thirty-two healthy individuals participated in the study. For the sliding-window analysis we used windows that were shifted by one volume at a time. Amygdala FC was calculated for each of these windows. Simultaneously acquired SCL time series were averaged over time frames that corresponded to the sliding-window FC analysis, which were subsequently regressed against the whole-brain seed-based amygdala sliding-window FC using the GLM. Surrogate time series were generated to test whether connectivity dynamics could have occurred by chance. In addition, results were contrasted against static amygdala FC and sliding-window FC of the primary visual cortex, which was chosen as a control seed, while a physio-physiological interaction (PPI) was performed as cross-validation. During periods of increased SCL, the left amygdala became more strongly coupled with the bilateral insula and anterior cingulate cortex, core areas of the salience network. The sliding-window analysis yielded a connectivity pattern that was unlikely to have occurred by chance, was spatially distinct from static amygdala FC and from sliding-window FC of the primary visual cortex, but was highly comparable to that of the PPI analysis. We conclude that sliding-window analysis can reveal functionally relevant fluctuations in connectivity in the context of an externally cued task.


Assuntos
Tonsila do Cerebelo/fisiologia , Nível de Alerta , Mapeamento Encefálico/métodos , Medo/fisiologia , Adulto , Encéfalo/fisiologia , Condicionamento Clássico , Feminino , Resposta Galvânica da Pele , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Adulto Jovem
8.
Eur Arch Psychiatry Clin Neurosci ; 267(6): 551-565, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28039553

RESUMO

Emotion instability in borderline personality disorder (BPD) has been associated with an impaired fronto-limbic inhibitory network. However, functional connectivity (FC) underlying altered emotion regulation in BPD has yet to be established. Here, we used resting-state fMRI to investigate enduring effects of effortful emotion regulation on the amygdala intrinsic FC in BPD. In this multicenter study, resting-state fMRI was acquired before and after an emotion regulation task in 48 BPD patients and 39 non-patient comparison individuals. The bilateral amygdalae were used as a seed in the whole-brain FC analysis and two-way mixed ANOVA to test whether BPD patients exhibited weaker post-task increase in the amygdala intrinsic FC with the prefrontal cortex (PFC), compared to non-patients. Subsequently, we explored whether the results are common for personality disorders characterized by emotional problems, using additional data of 21 cluster-C personality disorder patients. In contrast to non-patients, BPD patients failed to show increased post-task amygdala resting-state FC with the medial, dorsolateral, ventrolateral PFC, and superior temporal gyrus, but surprisingly exhibited decreased FC with the posterior cingulate cortex and increased FC with the superior parietal lobule. In BPD patients, the emotion regulation task failed to increase resting-state amygdala FC with brain regions essential for effortful emotion regulation, which suggests: (a) altered cognitive control typically used to indirectly alleviate distress by reinterpreting the meaning of emotional stimuli; (b) impaired direct regulation of emotional responses, which might be common for personality disorders;


Assuntos
Tonsila do Cerebelo/fisiopatologia , Transtorno da Personalidade Borderline/fisiopatologia , Conectoma/métodos , Emoções/fisiologia , Córtex Pré-Frontal/fisiopatologia , Autocontrole , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Transtorno da Personalidade Borderline/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
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