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Low-frequency fluctuation in continuous real-time feedback of finger force: a new paradigm for sustained attention

Zhang-Ye Dong, Dong-Qiang Liu, Jue Wang, Zhao Qing, Zhen-Xiang Zang, Chao-Gan Yan, Yu-Feng Zang
2012 Neuroscience Bulletin  
The mean finger force was not significantly different between the two states. fMRI data analysis showed higher fractional amplitude of low-frequency fluctuation (fALFF) in the S-FFF than in the RT-FFF  ...  Methods We compared the low-frequency fluctuations in both behavioral and fMRI data from 38 healthy adults (19 males; mean age, 22.3 years).  ...  Since the study by Biswal et al. in 1995 [28] , resting-state fMRI (RS-fMRI) has been widely applied in both basic and clinical studies to investigate the low-frequency (<0.1 Hz) fluctuation (LFF) of  ... 
doi:10.1007/s12264-012-1254-2 pmid:22833043 pmcid:PMC5561895 fatcat:pxi4hjdcqffffpx3xbmnzpakny

Concurrent tACS-fMRI Reveals Causal Influence of Power Synchronized Neural Activity on Resting State fMRI Connectivity

Marc Bächinger, Valerio Zerbi, Marius Moisa, Rafael Polania, Quanying Liu, Dante Mantini, Christian Ruff, Nicole Wenderoth
2017 Journal of Neuroscience  
Resting state fMRI (rs-fMRI) is commonly used to study the brain's intrinsic neural coupling, which reveals specific spatiotemporal patterns in the form of resting state networks (RSNs).  ...  It was suggested that slowly fluctuating power envelopes of electrophysiological signals synchronize across brain areas and that the topography of this activity is spatially correlated to resting state  ...  A total of 35 min of resting state fMRI was recorded, split into 5 runs of 7 min from the same 20 subjects as in the EEG experiment (see Materials and Methods).  ... 
doi:10.1523/jneurosci.1756-16.2017 pmid:28385876 fatcat:zbf5vvfkibdgpcipsxno2u6z5y

Electroencephalographic signatures of attentional and cognitive default modes in spontaneous brain activity fluctuations at rest

H. Laufs, K. Krakow, P. Sterzer, E. Eger, A. Beyerle, A. Salek-Haddadi, A. Kleinschmidt
2003 Proceedings of the National Academy of Sciences of the United States of America  
Spontaneous power fluctuations of electrical rhythms were determined for multiple discrete frequency bands, and associated fMRI signal modulations were mapped on a voxelby-voxel basis.  ...  We assessed the relation between hemodynamic and electrical indices of brain function by performing simultaneous functional MRI (fMRI) and electroencephalography (EEG) in awake subjects at rest with eyes  ...  We thank our volunteers for participation, the Institute of Neuroradiology for scanner access, and Anne-Lise Giraud and Richard Frackowiak for helpful comments.  ... 
doi:10.1073/pnas.1831638100 pmid:12958209 pmcid:PMC196925 fatcat:ngtz2rrprrcavmpzt6zgvpvgki

Mitochondrial Functional State Impacts Spontaneous Neocortical Activity and Resting State fMRI

Basavaraju G. Sanganahalli, Peter Herman, Fahmeed Hyder, Sridhar S. Kannurpatti, Stephane Gasman
2013 PLoS ONE  
As resting state fMRI-BOLD fluctuations and stimulus-evoked BOLD responses have similar physiological origins [1] and stimulus-evoked neuronal and hemodynamic responses are modulated by mitochondrial Ca  ...  We conclude that increased or decreased mitochondrial Ca 2+ uptake capacities lead to diminished resting state modes of brain functional connectivity.  ...  (TIF) Figure S2 mCU modulation reduced the spectral power of the low frequency (,0.1 Hz) R-fMRI BOLD fluctuations.  ... 
doi:10.1371/journal.pone.0063317 pmid:23650561 pmcid:PMC3641133 fatcat:c2rmeczndbcrrietsvigw3w7uq

The Noisy Brain: Power of Resting-State Fluctuations Predicts Individual Recognition Performance

Shany Grossman, Erin M. Yeagle, Michal Harel, Elizabeth Espinal, Roy Harpaz, Niv Noy, Pierre Mégevand, David M. Groppe, Ashesh D. Mehta, Rafael Malach
2019 Cell Reports  
We show that amplitudes of slow (<1 Hz) spontaneous fluctuations in high-frequency power measured during rest were predictive of the patients' performance in a visual recognition 1-back task (26 patients  ...  Here, we present intracranial electroencephalogram (iEEG) measurements in humans pointing to resting-state cortical "noise" as a possible neurophysiological trait that limits visual recognition capacity  ...  This bias may result from the power-law behavior of resting-state fluctuations in which low frequencies of HFB power modulations have larger amplitude and may therefore be less susceptible to measurement  ... 
doi:10.1016/j.celrep.2019.11.081 pmid:31851911 fatcat:yf7bvykqq5de7i5xken5hnrf4e

Concurrent tACS-fMRI Reveals Causal Influence Of Power Synchronized Neural Activity On Resting State fMRI Connectivity [article]

Marc Baechinger, Valerio Zerbi, Marius Moisa, Rafael Polania, Quanying Liu, Dante Mantini, Christian Ruff, Nicole Wenderoth
2017 bioRxiv   pre-print
Resting state fMRI (rs-fMRI) is commonly used to study the brain's intrinsic neural coupling, which reveals specific spatiotemporal patterns in the form of resting state networks (RSN).  ...  The two driving tACS signals were tailored to the individual's alpha rhythm (8-12 Hz) and fluctuated in amplitude according to a 1 Hz power envelope.  ...  Moreover, it is in line with previous research suggesting that low frequency components of the LFP (Lu et al., 2014) as well as low-frequency .  ... 
doi:10.1101/122820 fatcat:m74hgfwdyndbbmgitp6fqr2wsi

Biophysical Modulations of Functional Connectivity

Scott J. Peltier, Yash Shah
2011 Brain Connectivity  
Resting-state low frequency oscillations have been detected in many functional magnetic resonance imaging (MRI) studies and appear to be synchronized between functionally related areas.  ...  This review will present the biophysical characterization of functional connectivity, and examine the effects of physical state manipulations (such as anesthesia, fatigue, and aging) in healthy controls  ...  Rachael Seidler (University of Michigan) for helpful discussions and also the anonymous reviewers for their constructive criticism.  ... 
doi:10.1089/brain.2011.0039 pmid:22432417 fatcat:gahk642y2jdcnio45qbjsi5r2m

Short timescale abnormalities in the states of spontaneous synchrony in the functional neural networks in Alzheimer's disease

Tatiana A. Sitnikova, Jeremy W. Hughes, Seppo P. Ahlfors, Mark W. Woolrich, David H. Salat
2018 NeuroImage: Clinical  
fluctuations recorded by fMRI translates to much faster timescales of memory and other cognitive processes.  ...  To understand the relationship between this disruption in large-scale synchrony and the cognitive impairment in AD, it is critical to determine whether and how the deficit in the low frequency hemodynamic  ...  Acknowledgements This research was carried out in whole or in part at the Athinoula A.  ... 
doi:10.1016/j.nicl.2018.05.028 pmid:30094163 pmcid:PMC6077178 fatcat:5pfknipi2rc3llyg3uwb557neu

Association of thalamic hyperactivity with treatment-resistant depression and poor response in early treatment for major depression: a resting-state fMRI study using fractional amplitude of low-frequency fluctuations

T Yamamura, Y Okamoto, G Okada, Y Takaishi, M Takamura, A Mantani, A Kurata, Y Otagaki, H Yamashita, S Yamawaki
2016 Translational Psychiatry  
To identify brain region differences in spontaneous neural activity between patients with and without TRD, we assessed fractional amplitude of low-frequency fluctuations (fALFF).  ...  Sixteen patients with TRD, 16 patients with early-phase non-TRD and 26 healthy control (HC) subjects underwent resting-state functional magnetic resonance imaging.  ...  infrequently used, another resting-state fMRI method assesses the amplitude of low-frequency fluctuations (ALFF). 10 Because ALFF is higher in gray matter than in white matter, 9 and observed neural  ... 
doi:10.1038/tp.2016.18 pmid:26954981 pmcid:PMC4872444 fatcat:qkvy2446nfftbhxwffawyrx2xu

Altered functional integration of brain activity is a marker of impaired cognitive performance following sleep deprivation [article]

Nathan Cross, Florence B Pomares, Alex Nguyen, Aurore A Perrault, Aude Jegou, Makoto Uji, Kangjoo Lee, Fatemeh Razavipour, Obai Bin Ka'b Ali, Umit Aydin, Habib Benali, Christophe Grova (+1 others)
2020 bioRxiv   pre-print
The ratio of within vs between network integration in the cortex increased further in the NREM sleep, suggesting that prolonged wakefulness drives the cortex toward a state resembling sleep.  ...  The relative ration of within-between network integration in the sleep deprived state was tightly associated with deficits in cognitive performance.  ...  Evidence from resting state fMRI studies have demonstrated that SD results in increased time spent in dynamic states associated with low vigilance (Li et al. 2020 , Teng et al. 2019 , Xu et al. 2018 ,  ... 
doi:10.1101/2020.11.28.402305 fatcat:ml2minpfdvcmvjvu4vme6oxlj4

Combining fMRI with EEG and MEG in order to relate patterns of brain activity to cognition

2009 International Journal of Psychophysiology  
Here the requisite patterns are predicted to be large-scale spatial amplitude modulation (AM) of synchronized neuronal signals in the beta and gamma ranges that are coordinated but not correlated with  ...  Here the requisite patterns are predicted to be large-scale spatial amplitude modulation (AM) of synchronized neuronal signals in the beta and gamma ranges that are coordinated but not correlated with  ...  The MRI of the human subject was provided by Jeff H. Duyn and Tom Holroyd at the National Institute of Mental Health.  ... 
doi:10.1016/j.ijpsycho.2008.12.019 pmid:19233235 pmcid:PMC2746494 fatcat:gzc42bkl5falteksfgbyh4zv4i

Methods and Considerations for Dynamic Analysis of Functional MR Imaging Data

Jingyuan E. Chen, Mikail Rubinov, Catie Chang
2017 Neuroimaging clinics of North America  
First, it is far easier to observe variability than stability in data, especially as fMRI data are contaminated by noise and artifacts that are difficult to disentangle from fluctuations of neural origin  ...  In this article, we present an overview of methodological and interpretational considerations in this emerging field. task or stimuli (referred to as the "resting-state" condition 1 ).  ...  a considerable proportion of low-frequency BOLD signals.  ... 
doi:10.1016/j.nic.2017.06.009 pmid:28985928 pmcid:PMC5679015 fatcat:ufp4s2ygzzb5hpcizdf324g2di

Bridging multiple scales in the human brain using computational modelling [article]

Michael Schirner, Anthony Randal McIntosh, Viktor Jirsa, Gustavo Deco, Petra Ritter
2016 bioRxiv   pre-print
Lastly, large-scale interactions in the model lead to the emergence of scale-free power-law spectra.  ...  Further evaluation of the models show how balancing excitation with feedback inhibition generates an inverse relationship between α-rhythms and population firing on a faster time scale and resting-state  ...  Power-law relationships between frequency and amplitude of oscillations are omnipresent in nature; the identified mechanism-increased amplification of slower processes through prolonged recurrent excitation-may  ... 
doi:10.1101/085548 fatcat:mt6ho6jlprd7tizjvwdbubtp3e

Methods for cleaning the BOLD fMRI signal

César Caballero-Gaudes, Richard C. Reynolds
2017 NeuroImage  
Through the review, we summarize the importance of signal denoising as an essential step in the analysis pipeline of task-based and resting state fMRI studies.  ...  non-neuronal fluctuations of instrumental, physiological or subject-specific origin.  ...  in R & D [SEV-2015-490], and the research and writing of the paper were supported by the NIMH and NINDS Intramural Research Programs (ZICMH002888) of the NIH/HHS.  ... 
doi:10.1016/j.neuroimage.2016.12.018 pmid:27956209 pmcid:PMC5466511 fatcat:nexqgsdfmvd73grkzcfnrkhesm

Opposite Dynamics of GABA and Glutamate Levels in the Occipital Cortex during Visual Processing

Katarzyna Kurcyus, Efsun Annac, Nina M Hanning, Ashley D Harris, Georg Oeltzschner, Richard Edden, Valentin Riedl
2018 Journal of Neuroscience  
In relevant states, GABA and Glx correlated with amplitude of fMRI signal fluctuations. Furthermore, visual discriminatory performance correlated with the level of GABA, but not Glx.  ...  In this work, we study GABA and glutamate in three states of visual processing and in relation to fMRI and visual discriminatory performance in healthy people.  ...  In this study, however, it is not a major confounder, as we compare GABAϩ levels across different functional states of the visual system.  ... 
doi:10.1523/jneurosci.1214-18.2018 pmid:30282724 pmcid:PMC6234295 fatcat:cmzhlrnutzhmfmwoerxidvwluy
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