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Learning about brain physiology and complexity from the study of the epilepsies

GARCIA-CAIRASCO, N.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
241.59871%
The brain is a complex system, which produces emergent properties such as those associated with activity-dependent plasticity in processes of learning and memory. Therefore, understanding the integrated structures and functions of the brain is well beyond the scope of either superficial or extremely reductionistic approaches. Although a combination of zoom-in and zoom-out strategies is desirable when the brain is studied, constructing the appropriate interfaces to connect all levels of analysis is one of the most difficult challenges of contemporary neuroscience. Is it possible to build appropriate models of brain function and dysfunctions with computational tools? Among the best-known brain dysfunctions, epilepsies are neurological syndromes that reach a variety of networks, from widespread anatomical brain circuits to local molecular environments. One logical question would be: are those complex brain networks always producing maladaptive emergent properties compatible with epileptogenic substrates? The present review will deal with this question and will try to answer it by illustrating several points from the literature and from our laboratory data, with examples at the behavioral, electrophysiological, cellular and molecular levels. We conclude that...

Medidas de fluxo de informação com aplicação em neurociência; Measure of information flow with application in neuroscience

Takahashi, Daniel Yasumasa
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 15/01/2009 PT
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Inferência da força de interação nos fenômenos físicos/biológicos é objetivo comum a diversas áreas da ciência. Em particular, nas neurociências tem-se assistido a uma mudança no paradigma experimental em que a atenção tem-se voltado à compreensão da interação entre grupamentos neuronais. Em vista desta demanda surgiram naturalmente diversos métodos estatísticos de medida de dependência entre grupamentos neurais. Alguns foram desenhados para inferência de fluxo de informação, sem contudo precisar o que se entende por fluxo de informação, gerando consequentemente controvérsias na literatura. O principal objetivo deste trabalho é aplicar os conceitos da Teoria da Informação na análise de processos estacionários de segunda ordem para precisar as idéias de fluxo de informação utilizadas na literatura de forma ad hoc e obter um melhor entendimento da relação existente entre as diferentes medidas de dependência propostas.; We study the relationship between different measures of causality or information flow. We show that the concept of partial measures of dependence are related to the definition of inverse random variables.

A contribuição do neuromarketing para o estudo do comportamento do consumidor; Neuromarketing´s contribution to consumer behaviour studies

Colaferro, Claudia Almeida
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 16/12/2011 PT
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À medida que se avança no século XXI observamos a diversidade humana, cada vez em maior número, convivendo e interagindo a todo o momento. As dificuldades aumentam quando a diversidade se dá além de diferentes sexos, idades, mas também por diferentes opiniões e as várias formas de expressão e comportamento das pessoas, principalmente aqueles não conscientes. Nesse contexto vive-se o desencadeamento de uma crise das metodologias clássicas de investigação, vistas como limitantes e pouco esclarecedoras para o entendimento de que, em um mesmo indivíduo, podem existir estilos de consumo distintos, não conscientes, além de que o entrevistado pode, de maneira intencional ou não intencional, compreender mal, interpretar mal ou até mesmo enganar o pesquisador. O objetivo da dissertação foi avaliar se o neuromarketing pode ser uma nova área de colaboração ao entendimento do consumidor, ser capaz de obter as informações não declaradas do indivíduo, pela captura das informações cerebrais, adicionando assim conhecimento para o processo do entendimento de seu comportamento de consumo, validando-o como uma nova área de cooperação. Por meio de revisão bibliográfica e pesquisa empírica buscou-se identificar, entender e com isso resumir conceitos básicos sobre o neuromarketing...

Um estudo sobre a motricidade e a percepção visual na neurociência através do olhar da filosofia de Merleau-Ponty; A study of motricity and visual perception in neuroscience seen trough the Merleau-Pontys philosophy

Bandeira, Marcio Leitão
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 10/02/2012 PT
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Este é um trabalho de cunho teórico, cujo objetivo foi analisar alguns aspectos da neurociência com a ajuda do pensamento do filósofo Merleau-Ponty. A estrutura do trabalho é apresentada nos seguintes capítulos: (1o) faz uma introdução do pensamento do filósofo no que diz respeito a sua análise da fisiologia clássica e moderna; (2o) apresenta a neurociência, restrita a assuntos discutidos pelo filósofo; (3o) os dois capítulos iniciais circunscrevem o domínio da filosofia e da ciência, e neste capítulo, guiado pelas análises do filósofo, apresenta-se o encontro entre eles. Adiciona-se ao capítulo a apresentação de autores que utilizam em sua metodologia de estudo as proposições do filósofo, terminando com uma análise do modo com que estes autores usam certos conceitos de Merleau-Ponty; (4o) propõe uma análise do fenômeno do membro fantasma por meio dos resultados do capítulo anterior. A fim de objetivar o encontro dos domínios, proposto neste trabalho, foi preciso desenvolver uma matriz composta por vetores que representam os temas centrais do primeiro capítulo de modo a proporcionar uma espécie de linguagem comum aos dois domínios. Os temas centrais compõem-se de uma análise dos pressupostos metodológicos de pesquisa...

A teoria neuronal de Santiago Ramón y Cajal; The neuron theory of Santiago Ramón y Cajal

Ferreira, Francisco Rômulo Monte
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 24/10/2013 PT
Relevância na Pesquisa
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A teoria neuronal prerroga a existência da unidade básica do sistema nervoso, o neurônio. A teoria neuronal foi proposta e formulada nas últimas décadas do século XIX. Ela é comumente associada ao nome de Santiago Ramón y Cajal (1852-1934), que a formulou em oposição à proposta de que o tecido nervoso é constituído por redes contínuas formadas por células nervosas. Os trabalhos de Ramón y Cajal são, portanto, considerados ponto de inflexão nas pesquisas em Neurociência. Este trabalho objetiva investigar a constituição da teoria neuronal de acordo com a formação do conceito de neurônio. A formação do conceito de neurônio está diretamente ligada ao conceito de plasticidade. Como parte da pesquisa, serão investigados os principais trabalhos de um dos mais fervorosos defensores do reticularismo, o italiano Camillo Golgi (1843-1926). Em linhas gerais, o trabalho pretende um exame da constituição da teoria neuronal a partir da formação do conceito de neurônio e do papel que o conceito de plasticidade teve na formulação do conceito de neurônio; The neuron theory prerogatives the existence of the basic unit of the nervous system, the neuron. The neuron theory was proposed and formulated in the last decades of the nineteenth century. It is commonly associated with the name of Santiago Ramón y Cajal (1852-1934)...

Learning about brain physiology and complexity from the study of the epilepsies

Garcia-Cairasco,N.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 EN
Relevância na Pesquisa
241.59871%
The brain is a complex system, which produces emergent properties such as those associated with activity-dependent plasticity in processes of learning and memory. Therefore, understanding the integrated structures and functions of the brain is well beyond the scope of either superficial or extremely reductionistic approaches. Although a combination of zoom-in and zoom-out strategies is desirable when the brain is studied, constructing the appropriate interfaces to connect all levels of analysis is one of the most difficult challenges of contemporary neuroscience. Is it possible to build appropriate models of brain function and dysfunctions with computational tools? Among the best-known brain dysfunctions, epilepsies are neurological syndromes that reach a variety of networks, from widespread anatomical brain circuits to local molecular environments. One logical question would be: are those complex brain networks always producing maladaptive emergent properties compatible with epileptogenic substrates? The present review will deal with this question and will try to answer it by illustrating several points from the literature and from our laboratory data, with examples at the behavioral, electrophysiological, cellular and molecular levels. We conclude that...

Neuroscience databases: tools for exploring brain structure-function relationships.

Kötter, R
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 29/08/2001 EN
Relevância na Pesquisa
241.59871%
Faster than ever, neuroscience is generating vast amounts of data that await cross-referencing, comparison, integration and interpretation in the endeavour to unravel the mechanisms of the brain. The complex, diverse and distributed nature of these data requires the development of advanced neuroinformatics methodologies for databases and associated tools that are now beginning to emerge. This paper presents an overview of current issues in the representation, integration and analysis of neuroscience data from molecular to brain systems levels, including issues of implementation, standardization, management, quality control, copyright, confidentiality and acceptance. Particular emphasis is given to integrative neuroinformatics approaches for exploring structure-function relationships in the brain.

Center for Behavioral Neuroscience: a prototype multi-institutional collaborative research center

Powell, Kelly R; Albers, H Elliott
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Publicado em 17/07/2006 EN
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The Center for Behavioral Neuroscience was launched in the fall of 1999 with support from the National Science Foundation, the Georgia Research Alliance, and our eight participating institutions (Georgia State University, Emory University, Georgia Institute of Technology, Morehouse School of Medicine, Clark-Atlanta University, Spelman College, Morehouse College, Morris Brown College). The CBN provides the resources to foster innovative research in behavioral neuroscience, with a specific focus on the neurobiology of social behavior. Center faculty working in collaboratories use diverse model systems from invertebrates to humans to investigate fear, aggression, affiliation, and reproductive behaviors. The addition of new research foci in reward and reinforcement, memory and cognition, and sex differences has expanded the potential for collaborations among Center investigators. Technology core laboratories develop the molecular, cellular, systems, behavioral, and imaging tools essential for investigating how the brain influences complex social behavior and, in turn, how social experience influences brain function.

BioMediator Data Integration: Beyond Genomics to Neuroscience Data

Wang, K.; Tarczy-Hornoch, P.; Shaker, R.; Mork, P.; Brinkley, J.F.
Fonte: American Medical Informatics Association Publicador: American Medical Informatics Association
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
241.59871%
The BioMediator system developed at the University of Washington (UW) provides a theoretical and practical foundation for data integration across diverse biomedical research domains and various data types. In this paper we demonstrate the generalizability of its architecture through its application to the UW Human Brain Project (HBP) for understanding language organization in the brain. We first describe the system architecture and the characteristics of the four data sources developed by the UW HBP. Second we present the process of developing the application prototype for HBP neuroscience researchers posing queries across these semantically and syntactically heterogeneous neurophysiologic data sources. Then we discuss the benefits and potential limitations of the BioMediator system as a general data integration solution for different user groups in genomic and neuroscience research domains.

Quantum physics in neuroscience and psychology: a neurophysical model of mind–brain interaction

Schwartz, Jeffrey M; Stapp, Henry P; Beauregard, Mario
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
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Neuropsychological research on the neural basis of behaviour generally posits that brain mechanisms will ultimately suffice to explain all psychologically described phenomena. This assumption stems from the idea that the brain is made up entirely of material particles and fields, and that all causal mechanisms relevant to neuroscience can therefore be formulated solely in terms of properties of these elements. Thus, terms having intrinsic mentalistic and/or experiential content (e.g. ‘feeling’, ‘knowing’ and ‘effort’) are not included as primary causal factors. This theoretical restriction is motivated primarily by ideas about the natural world that have been known to be fundamentally incorrect for more than three-quarters of a century. Contemporary basic physical theory differs profoundly from classic physics on the important matter of how the consciousness of human agents enters into the structure of empirical phenomena. The new principles contradict the older idea that local mechanical processes alone can account for the structure of all observed empirical data. Contemporary physical theory brings directly and irreducibly into the overall causal structure certain psychologically described choices made by human agents about how they will act. This key development in basic physical theory is applicable to neuroscience...

Interacting and paradoxical forces in neuroscience and society

Singh, Jennifer; Hallmayer, Joachim; Illes, Judy
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/2007 EN
Relevância na Pesquisa
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Discoveries in the field of neuroscience are a natural source of discourse among scientists and have long been disseminated to the public. Historically, as news of findings has travelled between communities, it has elicited both expected and unusual reactions. What scientific landmarks promote discourse within the professional community? Do the same findings achieve a place in the public eye? How does the media choose what is newsworthy, and why does the public react the way it does? Drawing on examples of past challenges at the crossroads of neuroscience and society and on a case study of trends in one neurogenetic disease, autism, we explore the dialectical forces interacting in scientific and public discourse.

Social neuroscience of child and adolescent depression

Miller, Anita
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
241.59871%
The social neuroscience of child and adolescent depression is inherently multidisciplinary. Depressive disorders beginning early in life can have serious developmental and functional consequences. Psychopathology research has described depression’s defining clinical and contextual features, and intervention research has characterized its response to treatment and prevention programs. Neuroendocrine, electrophysiological, and neuroimaging studies have identified core neurobiological aspects of early-onset mood disorders. These areas are reviewed using a developmental social neuroscience perspective for integrating disparate observations. The paper introduces a dynamic adaptive systems framework, and it discusses hedonic capacity, stress sensitivity, ruminative self-focus, and attentional impairments as fundamental components of mood disorders.

The circumplex model of affect: An integrative approach to affective neuroscience, cognitive development, and psychopathology

Posner, Jonathan; Russell, James A.; Peterson, Bradley S.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
241.59871%
The circumplex model of affect proposes that all affective states arise from cognitive interpretations of core neural sensations that are the product of two independent neurophysiological systems. This model stands in contrast to theories of basic emotions, which posit that a discrete and independent neural system subserves every emotion. We propose that basic emotion theories no longer explain adequately the vast number of empirical observations from studies in affective neuroscience, and we suggest that a conceptual shift is needed in the empirical approaches taken to the study of emotion and affective psychopathologies. The circumplex model of affect is more consistent with many recent findings from behavioral, cognitive neuroscience, neuroimaging, and developmental studies of affect. Moreover, the model offers new theoretical and empirical approaches to studying the development of affective disorders as well as the genetic and cognitive underpinnings of affective processing within the central nervous system.

Why Are Computational Neuroscience and Systems Biology So Separate?

De Schutter, Erik
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
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Despite similar computational approaches, there is surprisingly little interaction between the computational neuroscience and the systems biology research communities. In this review I reconstruct the history of the two disciplines and show that this may explain why they grew up apart. The separation is a pity, as both fields can learn quite a bit from each other. Several examples are given, covering sociological, software technical, and methodological aspects. Systems biology is a better organized community which is very effective at sharing resources, while computational neuroscience has more experience in multiscale modeling and the analysis of information processing by biological systems. Finally, I speculate about how the relationship between the two fields may evolve in the near future.

Some recent advances in basic neuroscience research in China

Poo, Mu-ming; Guo, Aike
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
241.59871%
Neuroscience as a distinct discipline or research programme has been a rather recent event in most Chinese universities and in the Chinese Academy of Sciences. However, the last few years have witnessed increased funding and an improved research environment for neuroscience, both of which facilitated an influx of Chinese neuroscientists trained abroad. In this review, we have highlighted some recent research advances made by neuroscientists in China. Based on our own expertise, this review is focused mainly on findings that have contributed to our understanding of the mechanisms underlying brain development, neural plasticity and cognitive processes, and neural degeneration.

The Brain Connectivity Workshops: Moving the frontiers of computational systems neuroscience

Stephan, Klaas Enno; Riera, Jorge J.; Deco, Gustavo; Horwitz, Barry
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
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Understanding the link between neurobiology and cognition requires that neuroscience moves beyond mere structure-function correlations. An explicit systems perspective is needed in which putative mechanisms of how brain function is constrained by brain structure are mathematically formalized and made accessible for experimental investigation. Such a systems approach critically rests on a better understanding of brain connectivity in its various forms. Since 2002, frontier topics of connectivity and neural system analysis have been discussed in a multidisciplinary annual meeting, the Brain Connectivity Workshop (BCW), bringing together experimentalists and theorists from various fields. This article summarizes some of the main discussions at the two most recent workshops, 2006 at Sendai, Japan, and 2007 at Barcelona, Spain: (i) investigation of cortical micro- & macrocircuits, (ii) models of neural dynamics at multiple scales, (iii) analysis of “resting state” networks, and (iv) linking anatomical to functional connectivity. Finally, we outline some central challenges and research trajectories in computational systems neuroscience for the next years.

Assesment of Caregiver Experiences and Their Influence on Global DNA Methylation within the Adolescent Hippocampus and Amygdala

Forster, Amy
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
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Tania Roth; Current neuroscience and developmental psychology research reveals that there are sensitive postnatal periods during which the developing brain has a high level of plasticity. Therefore, early-life experiences can shape neural circuits, determining the structural and functional aspects of brain and behavior throughout the lifespan. More precisely, early-caregiver experiences can produce epigenetic modifications, which are functional and heritable changes to the genome that do not alter the DNA sequence. This study focuses specifically on DNA methylation???an epigenetic alteration that is typically associated with gene silencing and transcriptional suppression???in the ventral hippocampus, dorsal hippocampus, and amygdala. Previous research with adult animals indicates that early-life stress or experiences with a caregiver can epigenetically alter genes in these two regions. However, studies have not examined whether such effects are present during adolescence. This study aimed to quantify levels of 5-methylcytosine (5-mC) within the genome of adolescent rats that were exposed to various caregiving experiences (aversive vs. nurturing) during the first postnatal week of life. Results indicate that exposure to aversive caregiving was associated with significantly higher 5-mC levels in the dorsal hippocampus...

Memristance can explain Spike-Time-Dependent-Plasticity in Neural Synapses

Bernabé Linares-Barranco; Teresa Serrano-Gotarredona
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Relevância na Pesquisa
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Interdisciplinary research broadens the view of particular problems yielding fresh and possibly unexpected insights. This is the case of neuromorphic engineering where technology and neuroscience cross-fertilize each other. For example, consider on one side the recently discovered memristor, postulated in 1974, thanks to research in nanotechnology electronics. On the other side, consider the mechanism known as Spike-Time-Dependent-Plasticity (STDP) which describes a neuronal synaptic learning mechanism that outperforms the traditional Hebbian synaptic plasticity proposed in 1949. STDP was originally postulated as a computer learning algorithm, and is being used by the machine intelligence and computational neuroscience community. At the same time its biological and physiological foundations have been reasonably well established during the past decade. If memristance and STDP can be related, then (a) recent discoveries in nanophysics and nanoelectronic principles may shed new lights into understanding the intricate molecular and physiological mechanisms behind STDP in neuroscience, and (b) new neuromorphic-like computers built out of nanotechnology memristive devices could incorporate the biological STDP mechanisms yielding a new generation of self-adaptive ultra-high-dense intelligent machines. Here we show that by combining memristance models with the electrical wave signals of neural impulses (spikes) converging from pre- and post-synaptic neurons into a synaptic junction...

A simulation study on different STDP models concerning localized gamma oscillations

Florian Hauser; Andreas Knoblauch; Günther Palm
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Poster
Relevância na Pesquisa
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Gamma oscillations are a prominent feature in experimental as well as theoretical descriptions of brain activity. One of the network models which has the capability to generate such oscillations is what we call a local cell assembly (CA), i.e. a group of neighboring neurons which are strongly interconnected in an excitatory manner. Postulated by experimenters and extensively used in theoretical studies, these local networks seem to be a good candidate for investigating the impact of biological constraints given by models of spike-timing-dependent plasticity (STDP) on local gamma oscillating structures in the mammalian brain. Therefore we fi tted a two-compartment neuron model with AMPA- and NMDA-receptor mediated synaptic currents to desired properties of a local CA, meaning pattern completion and after-activity. We simulated 100 recurrently connected neurons with fi xed axonal transmission delays. In addition, every neuron receives Poissonian spikes from 1000 input cells firing at low background rate. During simulation the network is stimulated every second by increasing the input rate 10-fold for 35 msec. As a quality measure for keeping or even enhancing the properties of the network, we counted the relative amount of synapses with increased synaptic strengths with reference to the initial values. Three phenomenological STDP models (Song et al....

Biological resource catalog: NIF and NeuroLex

Anita E. Bandrowski
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
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In the digital age one can find data and teaching materials on the web, however data and materials of a high quality are not always ranked very high on commercial search engines that look at the number of other sites that link to a page rather than the quality of the information. Additionally, many such materials are maintained within databases that are inaccessible to search technology. To solve these problems, the Neuroscience Information Framework (NIF: http://www.neuinfo.org) was created to aid the neuroscience community to discover useful digital resources, such as academic databases, and it has also developed a large digital catalog of resources that are related to neuroscience. NIF has developed a “resource ontology”, and synchronized to a large extent the effort with the BRO (biomedical resource ontology) and assigned all 4000+ digital resources within the catalog to one or more of these ontological categories, making it possible to discover for example: all atlases through the NIF catalog. The resource categories are: Data, Funding, Job, Material, People, Services, Software, and Training. Most of these comprise sub-categorizations, definitions and synonyms and they can be viewed in the Neurolex found at http://neurolex.org/wiki/Resource_Type_Hierarchy. Each “resource descriptor” has been coded in OWL format files and has a unique identifier as well as synonyms and subclasses to help search systems locate data. Cataloging efforts of digital resources are tricky because unlike publications they can change at any time...