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Infra slow frequency

Asaph Zylbertal, Yosef Yarom, Shlomo Wagner
Rhythmic neuronal activity of multiple frequency bands has been described in many brain areas and attributed to numerous brain functions. Among these, little is known about the mechanism and role of infra-slow oscillations, which have been recently demonstrated in the mouse accessory olfactory bulb (AOB). Along with prolonged responses to stimuli and distinct network connectivity, they inexplicably affect the AOB processing of social relevant stimuli. Here we show that assemblies of AOB mitral cells are synchronized by lateral interactions through chemical and electrical synapses...
February 1, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Lukasz Chrobok, Katarzyna Palus, Jagoda Stanislawa Jeczmien-Lazur, Anna Chrzanowska, Mariusz Kepczynski, Marian Henryk Lewandowski
The intergeniculate leaflet (IGL) of the thalamus is a retinorecipient structure implicated in orchestrating circadian rhythmicity. The IGL network is highly GABAergic and consists mainly of neuropeptide Y-synthesising and enkephalinergic neurons. A high density of GFAP-immunoreactive astrocytes has been observed in the IGL, with a probable function in guarding neuronal inhibition. Interestingly, putatively enkephalinergic IGL neurons generate action potentials with an infra-slow oscillatory (ISO) pattern in vivo in urethane anesthetised Wistar rats, under light-on conditions only...
December 30, 2016: Experimental Neurology
Craig G Richter, Mariana Babo-Rebelo, Denis Schwartz, Catherine Tallon-Baudry
A fundamental feature of the temporal organization of neural activity is phase-amplitude coupling between brain rhythms at different frequencies, where the amplitude of a higher frequency varies according to the phase of a lower frequency. Here, we show that this rule extends to brain-organ interactions. We measured both the infra-slow (~0.05Hz) rhythm intrinsically generated by the stomach - the gastric basal rhythm - using electrogastrography, and spontaneous brain dynamics with magnetoencephalography during resting-state with eyes open...
February 1, 2017: NeuroImage
C La, V A Nair, P Mossahebi, J Stamm, R Birn, M E Meyerand, V Prabhakaran
Functional networks in resting-state fMRI are identified by characteristics of their intrinsic low-frequency oscillations, more specifically in terms of their synchronicity. With advanced aging and in clinical populations, this synchronicity among functionally linked regions is known to decrease and become disrupted, which may be associated with observed cognitive and behavioral changes. Previous work from our group has revealed that oscillations within the slow-5 frequency range (0.01-0.027 Hz) are particularly susceptible to disruptions in aging and following a stroke...
2016: NeuroImage: Clinical
Zeynab Alshelh, Flavia Di Pietro, Andrew M Youssef, Jenna M Reeves, Paul M Macey, E Russell Vickers, Christopher C Peck, Greg M Murray, Luke A Henderson
The neural mechanisms underlying the development and maintenance of chronic neuropathic pain remain unclear. Evidence from human investigations suggests that neuropathic pain is associated with altered thalamic burst firing and thalamocortical dysrhythmia. Additionally, experimental animal investigations show that neuropathic pain is associated with altered infra-slow (<0.1 Hz) frequency oscillations within the dorsal horn and somatosensory thalamus. The aim of this investigation was to determine whether, in humans, neuropathic pain was also associated with altered infra-slow oscillations within the ascending "pain" pathway...
January 20, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Sophie Carron, Qiang Ying Li, Luce Vander Elst, Robert N Muller, Tatjana N Parac-Vogt, John A Capobianco
Linking multiple paramagnetic gadolinium(III)-chelates based on the 2-[4,7,10-tris(carboxymethyl)-1,4,7,10-tetraazacyclododec-1-yl]acetate (DOTA) ligand to the surface of NaGdF4:Yb(3+),Tm(3+) upconverting nanoparticles with an average particle size of 20 nm resulted in an assembly that has favorable properties for bimodal Magnetic Resonance Imaging (MRI) and Optical Imaging (OI). An improved synthetic pathway was used to couple the paramagnetic precursor to the nanoparticles. The nanoparticles were rendered water dispersible via citrate capping, leaving one acid group free for amide coupling with the mono-amino precursor of the DOTA ligand...
July 7, 2015: Dalton Transactions: An International Journal of Inorganic Chemistry
Damon Ketabi, Abalfazl Barkhordari, Seyyed Jalil Mirmohammadi, Amir Houshang Mehrparvar
BACKGROUND: Road accidents are a social phenomenon in different communities that its infra-structural dimensions of which as well as technologic failures such as road quality, and tech-nical faults of automobiles, need to be assessed in detail. Iran has the first order in the world for deadly road accidents. This study was designed to assess the association between aberrant behaviors of truck drivers and the incidence of road accidents in Yazd, center of Iran, in 2010. METHODS: This cross-sectional descriptive-analytic study was conducted on 300 truck drivers in Yazd...
2011: Health Promotion Perspectives
Tuija Hiltunen, Jussi Kantola, Ahmed Abou Elseoud, Pasi Lepola, Kalervo Suominen, Tuomo Starck, Juha Nikkinen, Jukka Remes, Osmo Tervonen, Satu Palva, Vesa Kiviniemi, J Matias Palva
Ongoing neuronal activity in the CNS waxes and wanes continuously across widespread spatial and temporal scales. In the human brain, these spontaneous fluctuations are salient in blood oxygenation level-dependent (BOLD) signals and correlated within specific brain systems or "intrinsic-connectivity networks." In electrophysiological recordings, both the amplitude dynamics of fast (1-100 Hz) oscillations and the scalp potentials per se exhibit fluctuations in the same infra-slow (0.01-0.1 Hz) frequency range where the BOLD fluctuations are conspicuous...
January 8, 2014: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Mikael Lundqvist, Pawel Herman, Matias Palva, Satu Palva, David Silverstein, Anders Lansner
Recordings of membrane and field potentials, firing rates, and oscillation amplitude dynamics show that neuronal activity levels in cortical and subcortical structures exhibit infra-slow fluctuations (ISFs) on time scales from seconds to hundreds of seconds. Similar ISFs are salient also in blood-oxygenation-level dependent (BOLD) signals as well as in psychophysical time series. Functional consequences of ISFs are not fully understood. Here, they were investigated along with dynamical implications of ISFs in large-scale simulations of cortical network activity...
December 2013: NeuroImage
Tomasz Blasiak, Artur Zawadzki, Marian Henryk Lewandowski
Multiplicity of oscillatory phenomena in a range of infra-slow frequencies (<0.01 Hz) has been described in mammalian brains at different levels of organisation. The significance and manifestation in physiology and/or behaviour of many brain infra-slow oscillations (ISO) remain unknown. Examples of this phenomenon are two types of ISO observed in the brains of urethane-anaesthetised rats: infra-slow, rhythmic changes in the rate of action potential firing in a few nuclei of the subcortical visual system and a sleep-like cycle of activation/deactivation visible in the EEG signal...
2013: PloS One
L Marzetti, S Della Penna, A Z Snyder, V Pizzella, G Nolte, F de Pasquale, G L Romani, M Corbetta
Resting state networks (RSNs) are sets of brain regions exhibiting temporally coherent activity fluctuations in the absence of imposed task structure. RSNs have been extensively studied with fMRI in the infra-slow frequency range (nominally <10(-1)Hz). The topography of fMRI RSNs reflects stationary temporal correlation over minutes. However, neuronal communication occurs on a much faster time scale, at frequencies nominally in the range of 10(0)-10(2)Hz. We examined phase-shifted interactions in the delta (2-3...
October 1, 2013: NeuroImage
Paolo Zanatta, Gianna Maria Toffolo, Elisa Sartori, Anna Bet, Fabrizio Baldanzi, Nivedita Agarwal, Eugene Golanov
In non-pulsatile cardiopulmonary bypass surgery, middle cerebral artery blood flow velocity (BFV) is characterized by infra-slow oscillations of approximately 0.06Hz, which are paralleled by changes in total EEG power variability (EEG-PV), measured in 2s intervals. Since the origin of these BFV oscillations is not known, we explored their possible causative relationships with oscillations in EEG-PV at around 0.06Hz. We monitored 28 patients undergoing non-pulsatile cardiopulmonary bypass using transcranial Doppler sonography and scalp electroencephalography at two levels of anesthesia, deep (prevalence of burst suppression rhythm) and moderate (prevalence of theta rhythm)...
May 15, 2013: NeuroImage
J Matias Palva, Satu Palva
Converging electrophysiological and neuroimaging data show that mammalian brain dynamics are governed by spontaneous modulations of neuronal activity levels in cortical and subcortical structures. The time scales of these fluctuations form a continuum from seconds to tens and hundreds of seconds corresponding to slow (0.1-1Hz), infra-slow (0.01-0.1Hz), and "ultradian" (<0.01Hz) frequency bands, respectively. We focus here on the spontaneous neuronal dynamics in the infra-slow frequency band, infra-slow fluctuations (ISFs), and explore their electrophysiological substrates and behavioral correlates...
October 1, 2012: NeuroImage
Andrew L Ko, Felix Darvas, Andrew Poliakov, Jeffrey Ojemann, Larry B Sorensen
The study of human brain electrophysiology has extended beyond traditional frequency ranges identified by the classical EEG rhythms, encompassing both higher and lower frequencies. Changes in high-gamma-band (>70 Hz) power have been identified as markers of local cortical activity. Fluctuations at infra-slow (<0.1 Hz) frequencies have been associated with functionally significant cortical networks elucidated using fMRI studies. In this study, we examined infra-slow changes in band-limited power across a range of frequencies (1-120 Hz) in the default mode network (DMN)...
August 10, 2011: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Magor L Lörincz, Freya Geall, Ying Bao, Vincenzo Crunelli, Stuart W Hughes
An increasing number of EEG and resting state fMRI studies in both humans and animals indicate that spontaneous low frequency fluctuations in cerebral activity at <0.1 Hz (infra-slow oscillations, ISOs) represent a fundamental component of brain functioning, being known to correlate with faster neuronal ensemble oscillations, regulate behavioural performance and influence seizure susceptibility. Although these oscillations have been commonly indicated to involve the thalamus their basic cellular mechanisms remain poorly understood...
2009: PloS One
S J Kang, V B Samoilov, Y S Yoon
Sensitivity of pyroelectric IR-detectors of slow thermal processes, especially of human body sensors, depends strongly on their response in the infra-low (~0.1 to 1 Hz) region of frequency spectrum. The main mechanisms of heat losses-heat conduction of environment, lateral heat conduction in the plane of sensitive element, and emission of radiation-are considered. Their influence on the low-frequency response of pyroelectric sensors is estimated. Exact solutions and simple expressions for quantitative description of main specific features of real systems are obtained...
1998: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
T Wollmann, A Nieto-Barco, F Montón-Alvarez, J Barroso-Ribal
INTRODUCTION: The heredodegenerative ataxias are a heterogeneous group of disorders affecting especially the cerebellum and its tracts. Magnetic resonance imaging (MRI) studies using quantitative methodology are scarce, particularly in Friedreich's ataxia (FA). On the other hand, slowness of information processing speed has been described in FA, but no empirical relation with MRI parameters has been established. OBJECTIVE: The aim of the present study was to quantitatively assess infra and supratentorial atrophy in patients with clinical diagnosis of FA and to establish the relationship with a information processing speed measure...
February 1, 2004: Revista de Neurologia
Barry Winn, Helena M Culhane, Bernard Gilmartin, Niall C Strang
PURPOSE: Pharmacological intervention with peripheral sympathetic transmission at ciliary smooth muscle neuro-receptor junctions has been used against a background of controlled parasympathetic activity to investigate the characteristics of autonomic control of ocular accommodation. METHODS: A continuously recording infra-red optometer was used to measure accommodation on a group of five visually normal emmetropic subjects under open- and closed-loop conditions...
September 2002: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
J J Lemaire
Intracranial pressure waves include fast waves (pulse and respiration) and slow waves. Only the latter are considered here. Since the definition of three wave types in the pioneering works of Janny (1950) and Lundberg (1960), their study of frequential characteristics shows they are included in a spectrum where three contiguous frequency bands are individualised: the B wave band (BW) between 8 x 10(-3) Hz and 50 x 10(-3) Hz; the Infra B band (IB) below 8 x 10(-3) Hz; and the Ultra B band (UB) beyond 50 x 10(-3) Hz to 200 x 10(-3) Hz...
1997: Annales Françaises D'anesthèsie et de Rèanimation
M Iida, M Igarashi, A Naitoh, K Ishida, K Endo, K Nomura, M Sakai
The pendular rotation test (non-damped) in a head-tilted position, 60 degrees backward and then rotated 45 degrees either to the right or left, was performed in 6 patients with benign paroxysmal positional vertigo. The stimulus mode was amplitude = 360 degrees, frequency = 0.1 Hz, and the maximal speed = 114 degrees/s. By this test procedure, it was possible to evaluate the excitability of vertical semicircular canals. Using an infra-red CCD camera and a personal computer system, the evoked nystagmus was analysed...
September 1997: ORL; Journal for Oto-rhino-laryngology and its related Specialties
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