Read by QxMD icon Read

Pre stimulus eeg oscillation

Danielle D Sliva, Christopher J Black, Paul Bowary, Uday Agrawal, Juan F Santoyo, Noah S Philip, Benjamin D Greenberg, Christopher I Moore, Stephanie R Jones
The (8-12 Hz) neocortical alpha rhythm is associated with shifts in attention across sensory systems, and is thought to represent a sensory gating mechanism for the inhibitory control of cortical processing. The present preliminary study sought to explore whether alpha frequency transcranial alternating current stimulation (tACS) could modulate endogenous alpha power in the somatosensory system, and whether the hypothesized modulation would causally impact perception of tactile stimuli at perceptual threshold...
2018: Frontiers in Psychology
Lihui Wang, Wenshuo Chang, Ruth M Krebs, C Nico Boehler, Jan Theeuwes, Xiaolin Zhou
Reward-predictive stimuli can increase an automatic response tendency, which needs to be counteracted by effortful response inhibition when this tendency is inappropriate for the current task. Here we investigated how the human brain implements this dynamic process by adopting a reward-modulated Simon task while acquiring EEG and fMRI data in separate sessions. In the Simon task, a lateral target stimulus triggers an automatic response tendency of the spatially corresponding hand, which needs to be overcome if the activated hand is opposite to what the task requires, thereby delaying the response...
October 25, 2018: Cerebral Cortex
Annika Susann Wienke, Canan Basar-Eroglu, Christina Schmiedt-Fehr, Birgit Mathes
Adolescents are easily distracted by novel items than adults. Maturation of the frontal cortex and its integration into widely distributed brain networks may result in diminishing distractibility with the transition into young adulthood. The aim of this study was to investigate maturational changes of brain activity during novelty processing. We hypothesized that during adolescence, timing and task-relevant modulation of frontal cortex network activity elicited by novelty processing improves, concurrently with increasing cognitive control abilities...
2018: Frontiers in Behavioral Neuroscience
Nara Ikumi, Mireia Torralba, Manuela Ruzzoli, Salvador Soto-Faraco
In everyday life multisensory events, such as a glass crashing on the floor, the different sensory inputs are often experienced as simultaneous, despite the sensory processing of sound and sight within the brain are temporally misaligned. This lack of cross-modal synchrony is the unavoidable consequence of different light and sound speeds, and their different neural transmission times in the corresponding sensory pathways. Hence, cross-modal synchrony must be reconstructed during perception. It has been suggested that spontaneous fluctuations in neural excitability might be involved in the temporal organisation of sensory events during perception and account for variability in behavioural performance...
October 1, 2018: European Journal of Neuroscience
Pedro Caldana Gordon, Debora Desideri, Paolo Belardinelli, Christoph Zrenner, Ulf Ziemann
BACKGROUND: The analysis of cortical responses to transcranial magnetic stimulation (TMS) recorded by electroencephalography (EEG) has been successfully applied to study human cortical physiology. However, in addition to the (desired) activation of cortical neurons and fibers, TMS also causes (undesired) indirect brain responses through auditory and somatosensory stimulation, which may contribute significantly to the overall EEG signal and mask the effects of intervention on direct cortical responses...
November 2018: Brain Stimulation
Thorben Hülsdünker, Heiko K Strüder, Andreas Mierau
A growing number of studies suggest the phase of ongoing alpha oscillations in the brain influences visual perception. However, it remained largely unconsidered if this is associated with a phase dependence of neurophysiological processes especially in the visual cortex. Therefore, this study investigated the link between the pre-stimulus oscillatory alpha phase and neural correlates of early visual perception. In 64 subjects a 64-channel EEG system was used to examine the phase dependence of pattern-reversal visual evoked potentials (VEP) in a visual perception experiment...
August 18, 2018: Neuroscience Letters
Eda Mizrak, Kamin Kim, Brooke Roberts, Daniel John Ragland, Cameron Carter, Charan Ranganath
Research on transcranial direct current stimulation (tDCS) has grown rapidly, but there is controversy regarding whether and how tDCS could impact memory performance. We report a study that addressed this question by examining the effects of oscillatory tDCS (otDCS) on subsequent episodic memory performance and concomitant recordings of neural oscillations. Neural oscillations in the theta band (4-7 Hz) have been shown to be important for episodic memory and especially for source memory retrieval. Here, we tested the effects of anodal otDCS at theta (5...
September 5, 2018: Cognitive Neuroscience
Zafer İşcan, Aaron Schurger, Marine Vernet, Jacobo D Sitt, Antoni Valero-Cabré
There has been a growing interest in the role of pre-stimulus oscillations on cortical excitability in visual and motor systems. Prior studies focused on the relationship between pre-stimulus neuronal activity and TMS-evoked motor evoked potentials (MEPs) have reported heterogeneous results. We aimed to assess the role of pre-stimulus neural activity on the latency of MEPs, which might enhance our understanding of the variability of MEP signals, and potentially provide information on the role played by cortical activity fluctuations in the excitability of corticospinal pathways...
November 2018: Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation Cérébrale
Jason Samaha, Bastien Boutonnet, Bradley R Postle, Gary Lupyan
Perceptual experience results from a complex interplay of bottom-up input and prior knowledge about the world, yet the extent to which knowledge affects perception, the neural mechanisms underlying these effects, and the stages of processing at which these two sources of information converge, are still unclear. In several experiments we show that language, in the form of verbal labels, both aids recognition of ambiguous "Mooney" images and improves objective visual discrimination performance in a match/non-match task...
April 26, 2018: Scientific Reports
Michael S Clayton, Nick Yeung, Roi Cohen Kadosh
Neural oscillations in the alpha band (7-13 Hz) are commonly associated with disengagement of visual attention. However, recent studies have also associated alpha with processes of attentional control and stability. We addressed this issue in previous experiments by delivering transcranial alternating current stimulation at 10 Hz over posterior cortex during visual tasks (alpha tACS). As this stimulation can induce reliable increases in EEG alpha power, and given that performance on each of our visual tasks was negatively associated with alpha power, we assumed that alpha tACS would reliably impair visual performance...
2018: Frontiers in Neuroscience
Anthony M Harris, Paul E Dux, Jason B Mattingley
Neural oscillations appear important for perception and attention processes because stimulus detection is dependent upon the phase of 7-11 Hz oscillations before stimulus onset. Previous work has examined stimulus detection at attended locations, but it is unknown whether unattended locations are also subject to phasic modulation by ongoing oscillatory activity, as would be predicted by theories proposing a role for neural oscillations in organizing general neural processing. Here, we recorded brain activity with EEG while human participants of both sexes detected brief visual targets preceded by a spatial cue and determined whether performance for cued (attended) and uncued (unattended) targets was influenced by oscillatory phase across a range of frequencies...
March 21, 2018: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Kota Suzuki, Yasuko Okumura, Yosuke Kita, Yuhei Oi, Haruo Shinoda, Masumi Inagaki
Activity in the alpha band of the electroencephalogram (EEG) reflects functional inhibition of the cerebral cortex. The superior frontal cortex (SFC) is known to control alpha activity. Based on this relationship between SFC and alpha, we hypothesized that SFC controlled alpha mediates proactive control over interference. In this study, we examined the relationship between SFC and alpha in the flanker task by simultaneously recording EEG and near infrared spectroscopy (NIRS). Forty participants performed a flanker task with occasional (compatible 75%, incompatible 25%) and successive (incompatible 100%) conditions...
June 2018: Neuroscience Research
Alex Milton, Christopher Pleydell-Pearce
Pre-stimulus phase has been shown to influence temporal judgments concerning order, causality and simultaneity. One hypothesis is that phase cycles frame discrete perceptual snapshots over time. Yet, existing studies have explored the effect of pre-stimulus phase on fine-grained temporal judgments whereas no study has shown whether pre-stimulus phase influences sub-second temporal judgments lasting several phase cycles. If effects of phase on fine-grained temporal judgments reflect perceptual framing, then the perception of longer intervals might show some dependency on the frequency of phase cycles...
October 2017: Cognitive Neuroscience
Biao Han, Rufin VanRullen
Predictive coding is an influential model emphasizing interactions between feedforward and feedback signals. Here, we investigated the temporal dynamics of these interactions. Two gray disks with different versions of the same stimulus, one enabling predictive feedback (a 3D-shape) and one impeding it (random-lines), were simultaneously presented on the left and right of fixation. Human subjects judged the luminance of the two disks while EEG was recorded. The choice of 3D-shape or random-lines as the brighter disk was used to assess the influence of feedback signals on sensory processing in each trial (i...
March 6, 2017: Scientific Reports
Sebastian Scholz, Signe Luisa Schneider, Michael Rose
Recently, elevated ongoing pre-stimulus beta power (13-17 Hz) at encoding has been associated with subsequent memory formation for visual stimulus material. It is unclear whether this activity is merely specific to visual processing or whether it reflects a state facilitating general memory formation, independent of stimulus modality. To answer that question, the present study investigated the relationship between neural pre-stimulus oscillations and verbal memory formation in different sensory modalities. For that purpose, a within-subject design was employed to explore differences between successful and failed memory formation in the visual and auditory modality...
2017: PloS One
Rob H J Van der Lubbe, Izabela Szumska, Małgorzata Fajkowska
New analysis techniques of the electroencephalogram (EEG) such as wavelet analysis open the possibility to address questions that may largely improve our understanding of the EEG and clarify its relation with related potentials (ER Ps). Three issues were addressed. 1) To what extent can early ERERP components be described as transient evoked oscillations in specific frequency bands? 2) Total EEG power (TP) after a stimulus consists of pre-stimulus baseline power (BP), evoked power (EP), and induced power (IP), but what are their respective contributions? 3) The Phase Reset model proposes that BP predicts EP, while the evoked model holds that BP is unrelated to EP; which model is the most valid one? EEG results on NoGo trials for 123 individuals that took part in an experiment with emotional facial expressions were examined by computing ERPs and by performing wavelet analyses on the raw EEG and on ER Ps...
2016: Advances in Cognitive Psychology
Matt Craddock, Ellen Poliakoff, Wael El-Deredy, Ekaterini Klepousniotou, Donna M Lloyd
Fluctuations of pre-stimulus oscillatory activity in the somatosensory alpha band (8-14Hz) observed using human EEG and MEG have been shown to influence the detection of supra- and peri-threshold somatosensory stimuli. However, some reports of touch occur even without a stimulus. We investigated the possibility that pre-stimulus alpha oscillations might also influence these false reports of touch - known as tactile misperceptions. We recorded EEG while participants performed the Somatic Signal Detection Task (SSDT), in which participants must detect brief, peri-threshold somatosensory targets...
February 2017: Neuropsychologia
Joshua Levitt, Hyunwoo J Choo, Kelsey A Smith, Brian W LeBlanc, Carl Y Saab
Recent studies in our laboratory showed that cortical theta oscillations correlate with pain in rodent models. In this study, we sought to validate our pre-clinical data using EEG recordings in humans during immersion of the hand in ice cold water, a moderately noxious stimulus. Power spectral analysis shows that an increase in pain score is associated with an increase in power amplitude within a frequency range of 6-7Hz at the frontal (Fz) electrode. These results are consistent with our previous pre-clinical animal studies and the clinical literature...
April 2017: Brain Research Bulletin
Zafer Iscan, Maria Nazarova, Tommaso Fedele, Evgeny Blagovechtchenski, Vadim V Nikulin
Inter- and intra-subject variability of the motor evoked potentials (MEPs) to TMS is a well-known phenomenon. Although a possible link between this variability and ongoing brain oscillations was demonstrated, the results of the studies are not consistent with each other. Exploring this topic further is important since the modulation of MEPs provides unique possibility to relate oscillatory cortical phenomena to the state of the motor cortex probed with TMS. Given that alpha oscillations were shown to reflect cortical excitability, we hypothesized that their power and variability might explain the modulation of subject-specific MEPs to single- and paired-pulse TMS (spTMS, ppTMS, respectively)...
2016: Frontiers in Human Neuroscience
Xiangyong Yuan, Haijiang Li, Peiduo Liu, Hong Yuan, Xiting Huang
Pre-stimulus oscillation activity in the brain continuously fluctuates, but it is correlated with subsequent behavioral and perceptual performance. Here, using fast Fourier transformation of pre-stimulus electroencephalograms, we explored how oscillatory power modulates the subsequent discrimination of perceived simultaneity from non-simultaneity in the audiovisual domain. We found that the over-scalp high beta (20-28Hz), parieto-occipital low beta (14-20Hz), and high gamma oscillations (55-80Hz) were significantly stronger before audition-then-vision sequence when they were judged as simultaneous rather than non-simultaneous...
September 2016: International Journal of Psychophysiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"