Theta Rhythm
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. Preventive Effects of Ellagic Acid on Nucleus Tractus Solitarius Electrical Activity and Oxidative Stress Altered by Cerebral Global Ischemia/Reperfusion in Rat
ABSTRACT Cerebral ischemia commonly occurs when the blood flow to the entire brain or some part of the brain is disrupted. Global cerebral ischemia attenuates the nucleus tractus solitaries (NTS) EEG rhythm, increases the free radicals production and brain inflammation. Ellagic acid (EA) has antioxidative and anti-inflammatory effects against neural damages.
Braz. arch. biol. technol.. Publicado em: 08/01/2018
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2. Dinâmica do sistema córtico-hipocampal durante o condicionamento contextual de medo / Cortico-hippocampal system dynamics during contextual fear conditioning
O estabelecimento das memórias de longo prazo requer uma efetiva comunicação do hipocampo com o neocortex. Um mecanismo plausível envolvido na comunicação neuronal e na plasticidade sináptica é a sincronização da atividade elétrica cerebral na frequência teta. Estudos recentes mostraram que a sincronização entre os ritmos teta do hipocampo e do
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 03/02/2012
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3. Em busca da região epileptiforme em pacientes com epilepsia do lobo temporal: métodos alternativos baseados em fMRI e EEG-fMRI / Searching for epileptiform region in patients with temporal lobe epilepsy: alternative methods based on fMRI and EEG-fMRI
Temporal lobe epilepsy (TLE) is the most common and resistant form of epilepsy to anti-epileptic drug. There are several types of anti-epileptic drugs used in seizure control. However, in some cases drug treatment is not effective and surgery to remove the epileptogenic zone (EZ) is a recommended alternative. EZ is a theoretical concept and there are many te
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/08/2011
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4. Desenvolvimento de uma tecnica multimodal associando eletroencefalografia e imagens funcionais po ressonancia magnetica para o estudo de memoria operacional : aplicação em individuos com epilepsia de lobo temporal mesial associada a atrofia hipocampal
In this work, a multimodal approach involving electroencefalography (EEG) and functional Magnetic Resonance Imaging (fMRI) was implemented in order to perform studies on working memory in a group of subjects including controls and patients with mesial temporal lobe epilepsy (MTLE) associated with left hippocampal atrophy. In order to do that, a series of mem
Publicado em: 2008
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5. Photic driving in the electroencephalogram of children and adolescents: harmonic structure and relation to the resting state
In order to identify latent bioelectrical oscillators, 15 normal subjects (aged 9-17 years, 8 males, 7 females) were subjected to intermittent photic stimulation. The EEG amplitude spectra corresponding to the 11 fixed frequencies of stimulation presented (3-24 Hz) were combined to form "profiles" of the driving reaction in the right occipital area. The driv
Brazilian Journal of Medical and Biological Research. Publicado em: 2001-12
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6. Networks of interneurons with fast and slow γ-aminobutyric acid type A (GABAA) kinetics provide substrate for mixed gamma-theta rhythm
During active exploration, hippocampal neurons exhibit nested rhythmic activity at theta (≈8 Hz) and gamma (≈40 Hz) frequencies. Gamma rhythms may be generated locally by interactions within a class of interneurons mediating fast GABAA (GABAA,fast) inhibitory postsynaptic currents (IPSCs), whereas theta rhythms traditionally are thought to be imposed ext
The National Academy of Sciences.
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7. LTD windows of the STDP learning rule and synaptic connections having a large transmission delay enable robust sequence learning amid background noise
Spike-timing-dependent synaptic plasticity (STDP) is a simple and effective learning rule for sequence learning. However, synapses being subject to STDP rules are readily influenced in noisy circumstances because synaptic conductances are modified by pre- and postsynaptic spikes elicited within a few tens of milliseconds, regardless of whether those spikes c
Springer Netherlands.
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8. Orthogonal arrangement of rhythm-generating microcircuits in the hippocampus
As a structure involved in learning and memory, the hippocampus functions as a network. The functional differentiation along the longitudinal axis of the hippocampus is poorly demarcated in comparison with the transverse axis. Using patch clamp recordings in conjunction with post hoc anatomy, we have examined the pattern of connectivity and the functional di
National Academy of Sciences.
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9. Analysis of gamma rhythms in the rat hippocampus in vitro and in vivo.
1. We have shown previously, with experimental and computer models, how a '40 Hz' (gamma) oscillation can arise in networks of hippocampal interneurones, involving mutual GABAA-mediated synaptic inhibition and a source of tonic excitatory input. Here, we explore implications of this model for some hippocampal network phenomena in the rat in vitro and in vivo
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10. Disinhibition of rat hippocampal pyramidal cells by GABAergic afferents from the septum.
1. Slices were prepared from rat forebrain to include both the septum and the hippocampus in order to examine the effects of septal stimulation on hippocampal inhibitory circuits. 2. Repetitive stimulation of septo-hippocampal fibres caused a maintained decrease in the frequency of spontaneous IPSPs recorded from CA3 pyramidal cells in the presence of antago