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theta rhythm

Rohit Marawar, Hsiang J Yeh, Chris Carnabatu, John M Stern
INTRODUCTION: The EEG rhythms demonstrate changes in frequency and power with spontaneous changes in behavioral state that do not have well understood metabolic correlates within the brain. To investigate this question and compare the temporal lobe theta and delta rhythms, resting-state functional MRI (fMRI) was obtained with simultaneous EEG. METHODS: Simultaneous EEG-fMRI was recorded from 14 healthy, sleep-deprived subjects in awake and drowsy states. Scalp electrodes corresponding to bilateral temporal lobes were used to calculate delta and theta band power...
October 18, 2016: Journal of Clinical Neurophysiology: Official Publication of the American Electroencephalographic Society
Claudio Del Percio, Wilhelmus Drinkenburg, Susanna Lopez, Francesco Infarinato, Jesper Frank Bastlund, Bettina Laursen, Jan T Pedersen, Ditte Zerlang Christensen, Gianluigi Forloni, Angelisa Frasca, Francesco M Noè, Marina Bentivoglio, Paolo Francesco Fabene, Giuseppe Bertini, Valeria Colavito, Jonathan Kelley, Sophie Dix, Jill C Richardson, Claudio Babiloni
Resting state electroencephalographic (EEG) rhythms reflect the fluctuation of cortical arousal and vigilance in a typical clinical setting, namely the EEG recording for few minutes with eyes closed (i.e., passive condition) and eyes open (i.e., active condition). Can this procedure be back-translated to C57 (wild type) mice for aging studies? On-going EEG rhythms were recorded from a frontoparietal bipolar channel in 85 (19 females) C57 mice. Male mice were subdivided into 3 groups: 25 young (4.5-6 months), 18 middle-aged (12-15 months), and 23 old (20-24 months) mice to test the effect of aging...
September 15, 2016: Neurobiology of Aging
Lars Wojtecki, Saskia Elben, Jan Vesper, Alfons Schnitzler
We investigated neurophysiological mechanisms of subthalamic nucleus involvement in verbal fluency by means of a verbal generation task. The subthalamic nucleus is thought to act as a behavioural go/no-go instance by means of oscillatory communication in theta band with the prefrontal cortex. Because subthalamic alpha-theta frequency stimulation has been shown to exert beneficial effects on verbal fluency in Parkinson's disease, we hypothesized that an alpha-theta oscillatory network involving the subthalamic nucleus underlies verbal generation task performance as a gating instance for speech execution...
October 8, 2016: European Journal of Neuroscience
Jesus Minguillon, Miguel A Lopez-Gordo, Francisco Pelayo
Stress assessment has been under study in the last years. Both biochemical and physiological markers have been used to measure stress level. In neuroscience, several studies have related modification of stress level to brain activity changes in limbic system and frontal regions, by using non-invasive techniques such as functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). In particular, previous studies suggested that the exhibition or inhibition of certain brain rhythms in frontal cortical areas indicates stress...
2016: Frontiers in Computational Neuroscience
Marleen Bink, Ilja L Bongers, Arne Popma, Tieme W P Janssen, Chijs van Nieuwenhuizen
BACKGROUND: Estimates of the effectiveness of neurofeedback as a treatment for attention-deficit hyperactivity disorder (ADHD) are mixed. AIMS: To investigate the long-term additional effects of neurofeedback (NFB) compared with treatment as usual (TAU) for adolescents with ADHD. METHOD: Using a multicentre parallel-randomised controlled trial design, 60 adolescents with a DSM-IV-TR diagnosis of ADHD receiving NFB+TAU (n=41) or TAU (n=19) were followed up...
March 2016: BJPsych Open
Xueliang Shang, Bo Xu, Qun Li, Baohui Zhai, Xiaxia Xu, Tao Zhang
This study aims to investigate if neural oscillations can play a role as a bridge between the alteration of glutamatergic system and emotional behaviors in simulated microgravity (SM) mice. Adult male C57BL/6J mice were randomly divided into two groups: SM and control groups. The animal model was established by hindlimb unloading (HU). The mice were exposed to HU continued for 14days. Weight and sucrose consumption were measured. The degree of anxious and depressive was evaluated by Open field test and Elevated plus maze test...
September 28, 2016: Behavioural Brain Research
Yannick Daviaux, Sylvain Cremoux, Jessica Tallet, David Amarantini, Christophe Cornu, Thibault Deschamps
It is known that anxiety (ANX) impairs action-perception coupling. This study tests whether this impairment could be associated with an alteration of the sensorimotor function. To this aim, the cortical activities underlying the sensorimotor function were recorded in twelve volunteers in a reach-to-grasp paradigm, in which the level of ANX and the position of a glass were manipulated. The experimental manipulation of the ANX-related somatosensory state was expected to prompt participants to underestimate their reaching-to-grasp capabilities while the sensorimotor-related oscillatory brain activities around the 6-Hz (θ) frequency over motor-related and parietal regions were expected to be modulated...
September 28, 2016: Neuroscience
Jianxia Cui, Laurel J Ng, Vladislav Volman
Mild traumatic brain injury (mTBI) often results in neurobehavioral aberrations such as impaired attention and increased reaction time. Diffusion imaging and post mortem analysis studies suggest that mTBI primarily affects myelinated axons in white matter tracts. In particular, corpus callosum, mediating inter-hemispheric information exchange, has been shown to be affected in mTBI. Yet little is known about the mechanisms linking the injury of myelinated callosal axons to the neurobehavioral sequelae of mTBI...
September 28, 2016: Journal of Neurophysiology
Stylianos Kouvaros, Costas Papatheodoropoulos
The hippocampal synapses display a conspicuous ability for long-term plasticity, which is thought to contribute to learning and memory. Previous research has shown that long-term potentiation (LTP) greatly differs between the dorsal (DH) and ventral (VH) CA1 hippocampal synapses when induced by high-frequency stimulation. In this study, using rat hippocampal slices and more physiologically relevant activity patterns based on the frequency of the theta rhythm (i.e., theta-burst stimulation, TBS) we found that the DH compared with the VH displayed a higher ability for induction and stability of NMDA receptor-dependent LTP of the field excitatory postsynaptic potential...
September 20, 2016: Hippocampus
Vitória Piai, Kristopher L Anderson, Jack J Lin, Callum Dewar, Josef Parvizi, Nina F Dronkers, Robert T Knight
Language is classically thought to be supported by perisylvian cortical regions. Here we provide intracranial evidence linking the hippocampal complex to linguistic processing. We used direct recordings from the hippocampal structures to investigate whether theta oscillations, pivotal in memory function, track the amount of contextual linguistic information provided in sentences. Twelve participants heard sentences that were either constrained ("She locked the door with the") or unconstrained ("She walked in here with the") before presentation of the final word ("key"), shown as a picture that participants had to name...
October 4, 2016: Proceedings of the National Academy of Sciences of the United States of America
Nina V Volf, Ludmila V Belousova, Gennady G Knyazev, Alexander V Kulikov
This study was aimed to localize the effects of 5-HTTLPR (serotonin-transporter-linked polymorphic region) on the age differences of spontaneous EEG activity in women using neuroimaging analysis sLORETA (Standardized Low Resolution brain Electromagnetic Tomography). DNA samples extracted from cheek swabs and resting-state EEG recorded at 60 standard leads were collected from young (YW, N=86, 18-35years) and older (OW, N=45; 55-80years) healthy women. We have shown that advanced age was associated with increased posterior EEG desynchronization in S'/S'...
September 8, 2016: International Journal of Psychophysiology
J Jesús Hernández-Pérez, Blanca E Gutiérrez-Guzmán, María E Olvera-Cortés
The theta rhythm is necessary for hippocampal-dependent spatial learning. It has been proposed that each hippocampal stratum can generate a current theta dipole. Therefore, considering that each hippocampal circuit (CA1, CA3, and Dentate Gyrus (DG)) contributes differently to distinct aspects of a spatial memory, the theta oscillations on each stratum and their couplings may exhibit oscillatory dynamics associated with different stages of learning. To test this hypothesis, the theta oscillations from five hippocampal strata were recorded in the rat during different stages of learning in a Morris maze...
September 8, 2016: Neuroscience
Voyko Kavcic, Bojan Zalar, Bruno Giordani
The finding that some older individuals report declines in aspects of cognitive functioning is becoming a frequently used criteria to identify elderly at risk for mild cognitive impairment (MCI) and dementia. Once concerns are identified in a community setting, however, effective means are necessary to pinpoint those individuals who should go on to more complex and costly diagnostic evaluations (e.g., functional imaging). We tested 44 African American volunteers endorsing cognitive concerns (37 females, 7 males) age≥65years with CogState battery subtests and recorded resting-state EEG, with eyes closed...
September 6, 2016: International Journal of Psychophysiology
A Korik, R Sosnik, N Siddique, D Coyle
A motion trajectory prediction (MTP) - based brain-computer interface (BCI) aims to reconstruct the three-dimensional (3D) trajectory of upper limb movement using electroencephalography (EEG). The most common MTP BCI employs a time series of bandpass-filtered EEG potentials (referred to here as the potential time-series, PTS, model) for reconstructing the trajectory of a 3D limb movement using multiple linear regression. These studies report the best accuracy when a 0.5-2Hz bandpass filter is applied to the EEG...
2016: Progress in Brain Research
Eric D Melonakos, John A White, Fernando R Fernandez
Hippocampal network oscillations are important for learning and memory. Theta rhythms are involved in attention, navigation, and memory encoding, whereas sharp wave-ripple complexes are involved in memory consolidation. Cholinergic neurons in the medial septum-diagonal band of Broca (MS-DB) influence both types of hippocampal oscillations, promoting theta rhythms and suppressing sharp wave-ripples. They also receive frequency-dependent hyperpolarizing feedback from hippocamposeptal connections, potentially affecting their role as neuromodulators in the septohippocampal circuit...
September 2, 2016: Hippocampus
Phillip Aitken, Alice Benoit, Yiwen Zheng, Bruno Philoxene, Anne Le Gall, Pierre Denise, Stephane Besnard, Paul F Smith
Permanent vestibular loss has detrimental effects on the hippocampus, resulting in a disruption to spatial learning and memory, hippocampal theta rhythm and place cell field spatial coherence. Little is known about the vestibular system-related hippocampal cholinergic transmission. Since the pharmacological blockade of muscarinic acetylcholine (ACh) receptors within the hippocampus produces deficits in learning and memory, we hypothesized that ACh receptors may at least partly support the integration of vestibular input...
August 29, 2016: Hippocampus
Carlo Cipolli, Michele Ferrara, Luigi De Gennaro, Giuseppe Plazzi
Recent advances in electrophysiological [e.g., surface high-density electroencephalographic (hd-EEG) and intracranial recordings], video-polysomnography (video-PSG), transcranial stimulation and neuroimaging techniques allow more in-depth and more accurate investigation of the neural correlates of dreaming in healthy individuals and in patients with brain-damage, neurodegenerative diseases, sleep disorders or parasomnias. Convergent evidence provided by studies using these techniques in healthy subjects has led to a reformulation of several unresolved issues of dream generation and recall [such as the inter- and intra-individual differences in dream recall and the predictivity of specific EEG rhythms, such as theta in rapid eye movement (REM) sleep, for dream recall] within more comprehensive models of human consciousness and its variations across sleep/wake states than the traditional models, which were largely based on the neurophysiology of REM sleep in animals...
July 28, 2016: Sleep Medicine Reviews
Ernest Mas-Herrero, Josep Marco-Pallarés
Reinforcement learning requires the dynamic interplay of several specialized networks distributed across the brain. A potential mechanism to establish accurate temporal coordination among these paths is through the synchronization of neuronal activity to a common rhythm of neuronal firing. Previous EEG studies have suggested that theta oscillatory activity might be crucial in the integration of information from motivational and attentional paths that converge into the medial Prefrontal Cortex (mPFC) during reward-guided learning...
August 15, 2016: NeuroImage
Mina Amiri, Birgit Frauscher, Jean Gotman
The interactions between different EEG frequency bands have been widely investigated in normal and pathologic brain activity. Phase-amplitude coupling (PAC) is one of the important forms of this interaction where the amplitude of higher frequency oscillations is modulated by the phase of lower frequency activity. Here, we studied the dynamic variations of PAC of high (gamma and ripple) and low (delta, theta, alpha, and beta) frequency bands in patients with focal epilepsy in different sleep stages during the interictal period, in an attempt to see if coupling is different in more or less epileptogenic regions...
2016: Frontiers in Human Neuroscience
Qian-Quan Sun, Chen Zhou, Weiguo Yang, Daniel Petrus
OBJECTIVE: To examine if mice with focal cortical dysplasia (FCD) develop spontaneous epileptic seizures and, if so, determine the key electroencephalography (EEG) features. METHODS: Unilateral single freeze lesions to the S1 region (SFLS1R) were made in postnatal day 0-1 pups to induce a neocortical microgyrus in the right cortical hemisphere. Continuous 24-h recordings with intracranial EEG electrodes and behavioral tests were performed in adult SFLS1R and sham-control mice to assess neurologic status...
October 2016: Epilepsia
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