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1.
Nat Methods ; 21(7): 1316-1328, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38918605

RESUMO

Contemporary pose estimation methods enable precise measurements of behavior via supervised deep learning with hand-labeled video frames. Although effective in many cases, the supervised approach requires extensive labeling and often produces outputs that are unreliable for downstream analyses. Here, we introduce 'Lightning Pose', an efficient pose estimation package with three algorithmic contributions. First, in addition to training on a few labeled video frames, we use many unlabeled videos and penalize the network whenever its predictions violate motion continuity, multiple-view geometry and posture plausibility (semi-supervised learning). Second, we introduce a network architecture that resolves occlusions by predicting pose on any given frame using surrounding unlabeled frames. Third, we refine the pose predictions post hoc by combining ensembling and Kalman smoothing. Together, these components render pose trajectories more accurate and scientifically usable. We released a cloud application that allows users to label data, train networks and process new videos directly from the browser.


Assuntos
Algoritmos , Teorema de Bayes , Gravação em Vídeo , Animais , Gravação em Vídeo/métodos , Aprendizado de Máquina Supervisionado , Computação em Nuvem , Software , Postura/fisiologia , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Comportamento Animal
2.
bioRxiv ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38915704

RESUMO

Methodological advances in neuroscience have enabled the collection of massive datasets which demand innovative approaches for scientific communication. Existing platforms for data storage lack intuitive tools for data exploration, limiting our ability to interact effectively with these brain-wide datasets. We introduce two public websites: (Data and Atlas) developed for the International Brain Laboratory which provide access to millions of behavioral trials and hundreds of thousands of individual neurons. These interfaces allow users to discover both the raw and processed brain-wide data released by the IBL at the scale of the whole brain, individual sessions, trials, and neurons. By hosting these data interfaces as websites they are available cross-platform with no installation. By releasing each site's code as a modular open-source framework, other researchers can easily develop their own web interfaces and explore their own data. As neuroscience datasets continue to expand, customizable web interfaces offer a glimpse into a future of streamlined data exploration and act as blueprints for future tools.

3.
bioRxiv ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37162966

RESUMO

Contemporary pose estimation methods enable precise measurements of behavior via supervised deep learning with hand-labeled video frames. Although effective in many cases, the supervised approach requires extensive labeling and often produces outputs that are unreliable for downstream analyses. Here, we introduce "Lightning Pose," an efficient pose estimation package with three algorithmic contributions. First, in addition to training on a few labeled video frames, we use many unlabeled videos and penalize the network whenever its predictions violate motion continuity, multiple-view geometry, and posture plausibility (semi-supervised learning). Second, we introduce a network architecture that resolves occlusions by predicting pose on any given frame using surrounding unlabeled frames. Third, we refine the pose predictions post-hoc by combining ensembling and Kalman smoothing. Together, these components render pose trajectories more accurate and scientifically usable. We release a cloud application that allows users to label data, train networks, and predict new videos directly from the browser.

4.
Hum Brain Mapp ; 45(4): e26539, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38124341

RESUMO

Decreased long-range temporal correlations (LRTC) in brain signals can be used to measure cognitive effort during task execution. Here, we examined how learning a motor sequence affects long-range temporal memory within resting-state functional magnetic resonance imaging signal. Using the Hurst exponent (HE), we estimated voxel-wise LRTC and assessed changes over 5 consecutive days of training, followed by a retention scan 12 days later. The experimental group learned a complex visuomotor sequence while a complementary control group performed tightly matched movements. An interaction analysis revealed that HE decreases were specific to the complex sequence and occurred in well-known motor sequence learning associated regions including left supplementary motor area, left premotor cortex, left M1, left pars opercularis, bilateral thalamus, and right striatum. Five regions exhibited moderate to strong negative correlations with overall behavioral performance improvements. Following learning, HE values returned to pretraining levels in some regions, whereas in others, they remained decreased even 2 weeks after training. Our study presents new evidence of HE's possible relevance for functional plasticity during the resting-state and suggests that a cortical subset of sequence-specific regions may continue to represent a functional signature of learning reflected in decreased long-range temporal dependence after a period of inactivity.


Assuntos
Aprendizagem , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Oxigênio
5.
Nat Methods ; 20(3): 403-407, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36864199

RESUMO

We describe an architecture for organizing, integrating and sharing neurophysiology data within a single laboratory or across a group of collaborators. It comprises a database linking data files to metadata and electronic laboratory notes; a module collecting data from multiple laboratories into one location; a protocol for searching and sharing data and a module for automatic analyses that populates a website. These modules can be used together or individually, by single laboratories or worldwide collaborations.


Assuntos
Laboratórios , Neurofisiologia , Bases de Dados Factuais
6.
Brain Struct Funct ; 227(3): 793-807, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34704176

RESUMO

In motor learning, sequence specificity, i.e. the learning of specific sequential associations, has predominantly been studied using task-based fMRI paradigms. However, offline changes in resting state functional connectivity after sequence-specific motor learning are less well understood. Previous research has established that plastic changes following motor learning can be divided into stages including fast learning, slow learning and retention. A description of how resting state functional connectivity after sequence-specific motor sequence learning (MSL) develops across these stages is missing. This study aimed to identify plastic alterations in whole-brain functional connectivity after learning a complex motor sequence by contrasting an active group who learned a complex sequence with a control group who performed a control task matched for motor execution. Resting state fMRI and behavioural performance were collected in both groups over the course of 5 consecutive training days and at follow-up after 12 days to encompass fast learning, slow learning, overall learning and retention. Between-group interaction analyses showed sequence-specific decreases in functional connectivity during overall learning in the right supplementary motor area (SMA). We found that connectivity changes in a key region of the motor network, the superior parietal cortex (SPC) were not a result of sequence-specific learning but were instead linked to motor execution. Our study confirms the sequence-specific role of SMA that has previously been identified in online task-based learning studies, and extends it to resting state network changes after sequence-specific MSL.


Assuntos
Mapeamento Encefálico , Córtex Motor , Aprendizagem , Imageamento por Ressonância Magnética , Córtex Motor/diagnóstico por imagem , Descanso
7.
Psychosom Med ; 83(6): 579-591, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34213860

RESUMO

OBJECTIVE: Mindfulness-based interventions (MBIs) have been found to be a promising approach for the treatment of recurrent courses of depression. However, little is known about their neural mechanisms. This functional magnetic resonance imaging study set out to investigate activation changes in corticolimbic regions during implicit emotion regulation. METHODS: Depressed patients with a recurrent lifetime history were randomized to receive a 2-week MBI (n = 16 completers) or psychoeducation and resting (PER; n = 22 completers). Before and after, patients underwent functional magnetic resonance imaging while labeling the affect of angry, happy, and neutral facial expressions and completed questionnaires assessing ruminative brooding, the ability to decenter from such thinking, and depressive symptoms. RESULTS: Activation decreased in the right dorsolateral prefrontal cortex (dlPFC) in response to angry faces after MBI (p < .01, voxel-wise family-wise error rate correction, T > 3.282; 56 mm3; Montreal Neurological Institute peak coordinate: 32, 24, 40), but not after PER. This change was highly correlated with increased decentring (r = -0.52, p = .033), decreased brooding (r = 0.60, p = .010), and decreased symptoms (r = 0.82, p = .005). Amygdala activation in response to happy faces decreased after PER (p < .01, family-wise error rate corrected; 392 mm3; Montreal Neurological Institute peak coordinate: 28, -4, -16), whereas the MBI group showed no significant change. CONCLUSIONS: The dlPFC is involved in emotion regulation, namely, reappraisal or suppression of negative emotions. Decreased right dlPFC activation might indicate that, after the MBI, patients abstained from engaging in elaboration or suppression of negative affective stimuli; a putatively important mechanism for preventing the escalation of negative mood.Trial Registration: The study is registered at ClinicalTrials.gov (NCT02801513; 16/06/2016).


Assuntos
Regulação Emocional , Atenção Plena , Depressão/diagnóstico por imagem , Depressão/terapia , Emoções , Expressão Facial , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem
8.
Neuron ; 109(11): 1769-1775, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33932337

RESUMO

Brainhack is an innovative meeting format that promotes scientific collaboration and education in an open, inclusive environment. This NeuroView describes the myriad benefits for participants and the research community and how Brainhacks complement conventional formats to augment scientific progress.


Assuntos
Comunicação , Internet , Neurociências/organização & administração , Congressos como Assunto , Guias de Prática Clínica como Assunto
9.
Neuroimage ; 225: 117528, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33157264

RESUMO

Understanding cortical organization is a fundamental goal of neuroscience that requires comparisons across species and modalities. Large-scale connectivity gradients have recently been introduced as a data-driven representation of the intrinsic organization of the cortex. We studied resting-state functional connectivity gradients in the mouse cortex and found robust spatial patterns across four data sets. The principal gradient of functional connectivity shows a striking overlap with an axis of neocortical evolution from two primordial origins. Additional gradients reflect sensory specialization and aspects of a sensory-to-transmodal hierarchy, and are associated with transcriptomic features. While some of these gradients strongly resemble observations in the human cortex, the overall pattern in the mouse cortex emphasizes the specialization of sensory areas over a global functional hierarchy.


Assuntos
Evolução Biológica , Neocórtex/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Animais , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Conectoma , Neuroimagem Funcional , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Neocórtex/fisiologia , Vias Neurais/fisiologia , Descanso
11.
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
12.
Sci Data ; 6: 180308, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30747911

RESUMO

We present a publicly available dataset of 227 healthy participants comprising a young (N=153, 25.1±3.1 years, range 20-35 years, 45 female) and an elderly group (N=74, 67.6±4.7 years, range 59-77 years, 37 female) acquired cross-sectionally in Leipzig, Germany, between 2013 and 2015 to study mind-body-emotion interactions. During a two-day assessment, participants completed MRI at 3 Tesla (resting-state fMRI, quantitative T1 (MP2RAGE), T2-weighted, FLAIR, SWI/QSM, DWI) and a 62-channel EEG experiment at rest. During task-free resting-state fMRI, cardiovascular measures (blood pressure, heart rate, pulse, respiration) were continuously acquired. Anthropometrics, blood samples, and urine drug tests were obtained. Psychiatric symptoms were identified with Standardized Clinical Interview for DSM IV (SCID-I), Hamilton Depression Scale, and Borderline Symptoms List. Psychological assessment comprised 6 cognitive tests as well as 21 questionnaires related to emotional behavior, personality traits and tendencies, eating behavior, and addictive behavior. We provide information on study design, methods, and details of the data. This dataset is part of the larger MPI Leipzig Mind-Brain-Body database.


Assuntos
Cognição , Emoções , Adulto , Fatores Etários , Idoso , Eletroencefalografia , Feminino , Alemanha , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Psicofisiologia/métodos , Adulto Jovem
13.
Cogn Affect Behav Neurosci ; 19(5): 1317, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30547376

RESUMO

Maria Fissler and Emilia Winnebeck also are affiliated at Department of Psychiatry and Psychotherapy, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany.

14.
Gigascience ; 7(7)2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982501

RESUMO

With recent improvements in human magnetic resonance imaging (MRI) at ultra-high fields, the amount of data collected per subject in a given MRI experiment has increased considerably. Standard image processing packages are often challenged by the size of these data. Dedicated methods are needed to leverage their extraordinary spatial resolution. Here, we introduce a flexible Python toolbox that implements a set of advanced techniques for high-resolution neuroimaging. With these tools, segmentation and laminar analysis of cortical MRI data can be performed at resolutions up to 500 µm in reasonable times. Comprehensive online documentation makes the toolbox easy to use and install. An extensive developer's guide encourages contributions from other researchers that will help to accelerate progress in the promising field of high-resolution neuroimaging.


Assuntos
Mapeamento Encefálico/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Informática Médica/métodos , Software , Algoritmos , Encéfalo/diagnóstico por imagem , Sistemas Computacionais , Humanos , Sistemas On-Line , Linguagens de Programação
15.
Trends Cogn Sci ; 22(1): 21-31, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29203085

RESUMO

Recent advances in mapping cortical areas in the human brain provide a basis for investigating the significance of their spatial arrangement. Here we describe a dominant gradient in cortical features that spans between sensorimotor and transmodal areas. We propose that this gradient constitutes a core organizing axis of the human cerebral cortex, and describe an intrinsic coordinate system on its basis. Studying the cortex with respect to these intrinsic dimensions can inform our understanding of how the spectrum of cortical function emerges from structural constraints.


Assuntos
Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Animais , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/crescimento & desenvolvimento , Humanos
16.
Cogn Affect Behav Neurosci ; 17(6): 1164-1175, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28975567

RESUMO

The error-related negativity (ERN), an evoked-potential that arises in response to the commission of errors, is an important early indicator of self-regulatory capacities. In this study we investigated whether brief mindfulness training can reverse ERN deficits in chronically depressed patients. The ERN was assessed in a sustained attention task. Chronically depressed patients (n = 59) showed significantly blunted expression of the ERN in frontocentral and frontal regions, relative to healthy controls (n = 18). Following two weeks of training, the patients (n = 24) in the mindfulness condition showed a significantly increased ERN magnitude in the frontal region, but there were no significant changes in patients who had received a resting control (n = 22). The findings suggest that brief training in mindfulness may help normalize aberrations in the ERN in chronically depressed patients, providing preliminary evidence for the responsiveness of this parameter to mental training.


Assuntos
Atenção/fisiologia , Encéfalo/fisiopatologia , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/terapia , Atenção Plena , Adulto , Doença Crônica , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Entrevista Psicológica , Masculino , Testes Neuropsicológicos , Tempo de Reação , Resultado do Tratamento
17.
Front Hum Neurosci ; 11: 340, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28701943

RESUMO

The spontaneous oscillatory activity in the human brain shows long-range temporal correlations (LRTC) that extend over time scales of seconds to minutes. Previous research has demonstrated aberrant LRTC in depressed patients; however, it is unknown whether the neuronal dynamics normalize after psychological treatment. In this study, we recorded EEG during eyes-closed rest in depressed patients (N = 71) and healthy controls (N = 25), and investigated the temporal dynamics in depressed patients at baseline, and after attending either a brief mindfulness training or a stress reduction training. Compared to the healthy controls, depressed patients showed stronger LRTC in theta oscillations (4-7 Hz) at baseline. Following the psychological interventions both groups of patients demonstrated reduced LRTC in the theta band. The reduction of theta LRTC differed marginally between the groups, and explorative analyses of separate groups revealed noteworthy topographic differences. A positive relationship between the changes in LRTC, and changes in depressive symptoms was observed in the mindfulness group. In summary, our data show that aberrant temporal dynamics of ongoing oscillations in depressive patients are attenuated after treatment, and thus may help uncover the mechanisms with which psychotherapeutic interventions affect the brain.

18.
Hum Brain Mapp ; 38(7): 3502-3515, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28397392

RESUMO

Obesity is a complex neurobehavioral disorder that has been linked to changes in brain structure and function. However, the impact of obesity on functional connectivity and cognition in aging humans is largely unknown. Therefore, the association of body mass index (BMI), resting-state network connectivity, and cognitive performance in 712 healthy, well-characterized older adults of the Leipzig Research Center for Civilization Diseases (LIFE) cohort (60-80 years old, mean BMI 27.6 kg/m2 ± 4.2 SD, main sample: n = 521, replication sample: n = 191) was determined. Statistical analyses included a multivariate model selection approach followed by univariate analyses to adjust for possible confounders. Results showed that a higher BMI was significantly associated with lower default mode functional connectivity in the posterior cingulate cortex and precuneus. The effect remained stable after controlling for age, sex, head motion, registration quality, cardiovascular, and genetic factors as well as in replication analyses. Lower functional connectivity in BMI-associated areas correlated with worse executive function. In addition, higher BMI correlated with stronger head motion. Using 3T neuroimaging in a large cohort of healthy older adults, independent negative associations of obesity and functional connectivity in the posterior default mode network were observed. In addition, a subtle link between lower resting-state connectivity in BMI-associated regions and cognitive function was found. The findings might indicate that obesity is associated with patterns of decreased default mode connectivity similar to those seen in populations at risk for Alzheimer's disease. Hum Brain Mapp 38:3502-3515, 2017. © 2017 Wiley Periodicals, Inc.

19.
Cereb Cortex ; 27(2): 981-997, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28184415

RESUMO

Research in the macaque monkey suggests that cortical areas with similar microstructure are more likely to be connected. Here, we examine this link in the human cerebral cortex using 2 magnetic resonance imaging (MRI) measures: quantitative  T1 maps, which are sensitive to intracortical myelin content and provide an in vivo proxy for cortical microstructure, and resting-state functional connectivity. Using ultrahigh-resolution MRI at 7 T and dedicated image processing tools, we demonstrate a systematic relationship between T1-based intracortical myelin content and functional connectivity. This effect is independent of the proximity of areas. We employ nonlinear dimensionality reduction to characterize connectivity components and identify specific aspects of functional connectivity that are linked to myelin content. Our results reveal a consistent spatial pattern throughout different analytic approaches. While functional connectivity and myelin content are closely linked in unimodal areas, the correspondence is lower in transmodal areas, especially in posteromedial cortex and the angular gyrus. Our findings are in agreement with comprehensive reports linking histologically assessed microstructure and connectivity in different mammalian species and extend them to the human cerebral cortex in vivo.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Bainha de Mielina/metabolismo , Mapeamento Encefálico/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Descanso , Software , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia , Adulto Jovem
20.
Brain Struct Funct ; 222(5): 2173-2182, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27807628

RESUMO

Connectivity between distant cortical areas is a valuable, yet costly feature of cortical organization and is predominantly found between regions of heteromodal association cortex. The recently proposed 'tethering hypothesis' describes the emergence of long-distance connections in association cortex as a function of their spatial separation from primary cortical regions. Here, we investigate this possibility by characterizing the distance between functionally connected areas along the cortical surface. We found a systematic relationship between an area's characteristic connectivity distance and its distance from primary cortical areas. Specifically, the further a region is located from primary sensorimotor regions, the more distant are its functional connections with other areas of the cortex. The measure of connectivity distance also captured major functional subdivisions of the cerebral cortex: unimodal, attention, and higher-order association regions. Our findings provide evidence for the anchoring role of primary cortical regions in establishing the spatial distribution of cortical properties that are related to functional specialization and differentiation.


Assuntos
Atenção/fisiologia , Córtex Cerebral/fisiologia , Rede Nervosa/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Adulto Jovem
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