Long-range phase synchronization of high-gamma activity in human cortex

AbstractInter-areal synchronization of neuronal oscillations below 100 Hz is ubiquitous in cortical circuitry and thought to regulate neuronal communication. In contrast, faster activities are generally considered to be exclusively local-circuit phenomena. We show with human intracerebral recordings that 100–300 Hz high-gamma activity (HGA) may be synchronized between widely distributed regions. HGA synchronization was not attributable to artefacts or to epileptic pathophysiology. Instead, HGA synchronization exhibited a reliable cortical connectivity and community structures, and a laminar profile opposite to that of lower frequencies. Importantly, HGA synchronization among functional brain systems during non-REM sleep was distinct from that in resting state. Moreover, HGA synchronization was transiently enhanced for correctly inhibited responses in a Go/NoGo task. These findings show that HGA synchronization constitutes a new, functionally significant form of neuronal spike-timing relationships in brain activity. We suggest that HGA synchronization reflects the temporal microstructure of spiking-based neuronal communication per se in cortical circuits.

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Long-range phase synchronization of high-frequency oscillations in human cortex

Nature Communications ◽

10.1038/s41467-020-18975-8 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

G. Arnulfo ◽

S. H. Wang ◽

V. Myrov ◽

B. Toselli ◽

J. Hirvonen ◽

...

Keyword(s):

High Frequency ◽

Large Scale ◽

Phase Synchronization ◽

Brain Activity ◽

Brain Regions ◽

Spike Timing ◽

Human Cortex ◽

Neuronal Communication ◽

High Frequency Oscillations ◽

Connectivity Patterns

Abstract Inter-areal synchronization of neuronal oscillations at frequencies below ~100 Hz is a pervasive feature of neuronal activity and is thought to regulate communication in neuronal circuits. In contrast, faster activities and oscillations have been considered to be largely local-circuit-level phenomena without large-scale synchronization between brain regions. We show, using human intracerebral recordings, that 100–400 Hz high-frequency oscillations (HFOs) may be synchronized between widely distributed brain regions. HFO synchronization expresses individual frequency peaks and exhibits reliable connectivity patterns that show stable community structuring. HFO synchronization is also characterized by a laminar profile opposite to that of lower frequencies. Importantly, HFO synchronization is both transiently enhanced and suppressed in separate frequency bands during a response-inhibition task. These findings show that HFO synchronization constitutes a functionally significant form of neuronal spike-timing relationships in brain activity and thus a mesoscopic indication of neuronal communication per se.

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Direct electrical stimulation of human cortex evokes high gamma activity that predicts conscious somatosensory perception

Journal of Neural Engineering ◽

10.1088/1741-2552/aa9bf9 ◽

2018 ◽

Vol 15 (2) ◽

pp. 026015 ◽

Cited By ~ 2

Author(s):

Leah Muller ◽

John D Rolston ◽

Neal P Fox ◽

Robert Knowlton ◽

Vikram R Rao ◽

...

Keyword(s):

Electrical Stimulation ◽

Gamma Activity ◽

Direct Electrical Stimulation ◽

Human Cortex ◽

High Gamma ◽

Stimulation Of

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Prefrontal High Gamma in ECoG tags periodicity of musical rhythms in perception and imagination

10.1101/784991 ◽

2019 ◽

Author(s):

S. A. Herff ◽

C. Herff ◽

A. J. Milne ◽

G. D. Johnson ◽

J. J. Shih ◽

...

Keyword(s):

Auditory Processing ◽

Right Hemisphere ◽

Brain Activity ◽

Activity Patterns ◽

Superior Temporal Gyrus ◽

Gamma Activity ◽

Rhythm Perception ◽

High Gamma ◽

The Right ◽

Musical Rhythms

AbstractRhythmic auditory stimuli are known to elicit matching activity patterns in neural populations. Furthermore, recent research has established the particular importance of high-gamma brain activity in auditory processing by showing its involvement in auditory phrase segmentation and envelope-tracking. Here, we use electrocorticographic (ECoG) recordings from eight human listeners, to see whether periodicities in high-gamma activity track the periodicities in the envelope of musical rhythms during rhythm perception and imagination. Rhythm imagination was elicited by instructing participants to imagine the rhythm to continue during pauses of several repetitions. To identify electrodes whose periodicities in high-gamma activity track the periodicities in the musical rhythms, we compute the correlation between the autocorrelations (ACC) of both the musical rhythms and the neural signals. A condition in which participants listened to white noise was used to establish a baseline. High-gamma autocorrelations in auditory areas in the superior temporal gyrus and in frontal areas on both hemispheres significantly matched the autocorrelation of the musical rhythms. Overall, numerous significant electrodes are observed on the right hemisphere. Of particular interest is a large cluster of electrodes in the right prefrontal cortex that is active during both rhythm perception and imagination. This indicates conscious processing of the rhythms’ structure as opposed to mere auditory phenomena. The ACC approach clearly highlights that high-gamma activity measured from cortical electrodes tracks both attended and imagined rhythms.

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Interactions between motor thalamic field potentials and single unit spiking predict behavior in rats

10.1101/642991 ◽

2019 ◽

Author(s):

Matt Gaidica ◽

Amy Hurst ◽

Christopher Cyr ◽

Daniel K. Leventhal

Keyword(s):

Task Performance ◽

Brain Activity ◽

Field Potential ◽

Spike Timing ◽

Delta Phase ◽

Beta Power ◽

High Gamma ◽

Gamma Power ◽

Complex Relationships ◽

And Behavior

AbstractThe thalamus plays a central role in generating circuit-level neural oscillations believed to coordinate brain activity over large spatiotemporal scales. Such thalamic influences are well-documented for sleep rhythms and in sensory systems, but the relationship between thalamic activity, motor circuit local field potential (LFP) oscillations, and behavior is unknown. We recorded wideband motor thalamic (Mthal) electrophysiology as healthy rats performed a two-alternative forced choice task. The power of delta (1−4 Hz), beta (13−30 Hz), low gamma (30−70 Hz), and high gamma (70−200 Hz) oscillations were strongly modulated by task performance. As in cortex, delta phase predicted beta/low gamma power and reaction time. Furthermore, delta phase differentially predicted spike timing in functionally distinct populations of Mthal neurons, which also predicted task performance and beta power. These complex relationships suggest mechanisms for commonly observed LFP-LFP and spike-LFP interactions, as well as subcortical influences on motor output.

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The Menstrual Cycle Alters Resting-State Cortical Activity: A Magnetoencephalography Study

Frontiers in Human Neuroscience ◽

10.3389/fnhum.2021.652789 ◽

2021 ◽

Vol 15 ◽

Author(s):

Rika Haraguchi ◽

Hideyuki Hoshi ◽

Sayuri Ichikawa ◽

Mayuko Hanyu ◽

Kohei Nakamura ◽

...

Keyword(s):

Menstrual Cycle ◽

Resting State ◽

Functional Neuroimaging ◽

Brain Activity ◽

Temporal Cortex ◽

Neural Oscillations ◽

Median Frequency ◽

Accurate Interpretation ◽

High Gamma ◽

The Right

Resting-state neural oscillations are used as biomarkers for functional diseases such as dementia, epilepsy, and stroke. However, accurate interpretation of clinical outcomes requires the identification and minimisation of potential confounding factors. While several studies have indicated that the menstrual cycle also alters brain activity, most of these studies were based on visual inspection rather than objective quantitative measures. In the present study, we aimed to clarify the effect of the menstrual cycle on spontaneous neural oscillations based on quantitative magnetoencephalography (MEG) parameters. Resting-state MEG activity was recorded from 25 healthy women with normal menstrual cycles. For each woman, resting-state brain activity was acquired twice using MEG: once during their menstrual period (MP) and once outside of this period (OP). Our results indicated that the median frequency and peak alpha frequency of the power spectrum were low, whereas Shannon spectral entropy was high, during the MP. Theta intensity within the right temporal cortex and right limbic system was significantly lower during the MP than during the OP. High gamma intensity in the left parietal cortex was also significantly lower during the MP than during the OP. Similar differences were also observed in the parietal and occipital regions between the proliferative (the late part of the follicular phase) and secretory phases (luteal phase). Our findings suggest that the menstrual cycle should be considered to ensure accurate interpretation of functional neuroimaging in clinical practice.

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A Preliminary Study of the Association Among Metacognition and Resting State EEG in Schizophrenia

Journal of Psychophysiology ◽

10.1027/0269-8803/a000153 ◽

2016 ◽

Vol 30 (2) ◽

pp. 47-54 ◽

Cited By ~ 2

Author(s):

Jenifer L. Vohs ◽

Bethany L. Leonhardt ◽

Michael M. Francis ◽

Daniel Westfall ◽

Josselyn Howell ◽

...

Keyword(s):

Resting State ◽

Brain Activity ◽

Gamma Activity ◽

Multiple Perspectives ◽

Behavioral Correlates ◽

Form Complex ◽

Gamma Frequency ◽

Gamma Range ◽

The World ◽

Gamma Power

Abstract. Metacognition refers to a spectrum of activities that range from the consideration of discrete mental experiences, such as a specific thought or emotion, to the synthesis of discrete perceptions into integrated representations of the self and others as unique agents in the world. Metacognitive deficits have been observed in schizophrenia and linked with a number of behavioral correlates and outcomes. Less is known however about the neural systems associated with such processes. Establishing the link between brain activity and metacognition therefore is an essential next step. Resting state electroencephalography (EEG) provides one possible avenue for investigating this link. EEG studies in schizophrenia suggest that the gamma frequency range may have functional significance and be related to the disturbed information processing often observed in the disorder. In the present investigation, we assessed metacognition among 20 individuals with prolonged schizophrenia using the Metacognition Assessment Scale Abbreviated, who also participated in resting state EEG recording. We hypothesized that gamma activity would be associated with those domains of metacognition that require the most integration to perform, Decentration and Mastery. We then examined the association among gamma power and each metacognitive domain. Additional exploratory analyses were conducted across a spectrum of EEG activity. We found that increased gamma activity at rest was linked with decreased decentration. This suggests that hyperactivity in the gamma range may index disrupted processing and integration, and ultimately the metacognitive processes needed to form complex ideas about oneself and others and to see the world from multiple perspectives. This link provides additional evidence of how the biological roots of schizophrenia may culminate in a disrupted life.

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The Role of Cortico-Thalamo-Cortical Circuits in Language: Recurrent Circuits Revisited

Neuropsychology Review ◽

10.1007/s11065-019-09421-8 ◽

2019 ◽

Cited By ~ 2

Author(s):

Bruce Crosson

Keyword(s):

Circuit Model ◽

Word Retrieval ◽

Gamma Activity ◽

Cortical Circuits ◽

Verbal Comprehension ◽

Cortical Circuitry ◽

Language Functions ◽

High Gamma ◽

Neural Signature

AbstractBased on a review of recent literature, a recurrent circuit model describes how cortico-thalamo-cortical and cortico-cortical circuitry supports word retrieval, auditory-verbal comprehension, and other language functions. Supporting data include cellular and layer-specific cortico-thalamic, thalamo-cortical, and cortico-cortical neuroanatomy and electrophysiology. The model posits that during word retrieval, higher order cortico-thalamo-cortical relays maintain stable representations of semantic information in feedforward processes at the semantic-lexical interface. These stable semantic representations are compared to emerging lexical solutions to represent the semantic construct to determine how well constructs are associated with each other. The resultant error signal allows cortico-cortical sculpting of activity between the semantic and lexical mechanisms until there is a good match between these two levels, at which time the lexical solution will be passed along to the cortical processor necessary for the next stage of word retrieval. Evidence is cited that high gamma activity is the neural signature for processing in the cortico-thalamo-cortical and cortico-cortical circuitry. Methods for testing hypotheses generated from this recurrent circuit model are discussed. Mathematical modeling may be a useful tool in exploring underlying properties of these circuits.

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