High Gamma Activity in Cortex and Hippocampus is Correlated with Autonomic Tone During Sleep

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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Classification of hand movement direction based on EEG high-gamma activity

2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society ◽

10.1109/embc.2014.6945119 ◽

2014 ◽

Cited By ~ 4

Author(s):

Carlos A. Loza ◽

Gavin R. Philips ◽

Mehrnaz Kh Hazrati ◽

Janis J. Daly ◽

Jose C. Principe

Keyword(s):

Hand Movement ◽

Gamma Activity ◽

Movement Direction ◽

High Gamma

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Rapid and Minimum Invasive Functional Brain Mapping by Real-Time Visualization of High Gamma Activity During Awake Craniotomy

World Neurosurgery ◽

10.1016/j.wneu.2014.08.009 ◽

2014 ◽

Vol 82 (5) ◽

pp. 912.e1-912.e10 ◽

Cited By ~ 20

Author(s):

Hiroshi Ogawa ◽

Kyousuke Kamada ◽

Christoph Kapeller ◽

Satoru Hiroshima ◽

Robert Prueckl ◽

...

Keyword(s):

Real Time ◽

Brain Mapping ◽

Awake Craniotomy ◽

Gamma Activity ◽

Functional Brain ◽

Functional Brain Mapping ◽

High Gamma ◽

Real Time Visualization

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Broadband High Gamma Activity as a Feature of Single Trial Brain Activation

NeuroImage ◽

10.1016/s1053-8119(09)71842-7 ◽

2009 ◽

Vol 47 ◽

pp. S171

Author(s):

J.S. Gehring ◽

J. Wentlandt ◽

I. Mutschler ◽

A. Schulze-Bonhage ◽

A. Aertsen ◽

...

Keyword(s):

Brain Activation ◽

Gamma Activity ◽

Single Trial ◽

High Gamma

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High-gamma activity in the human hippocampus and parahippocampus during inter-trial rest periods of a virtual navigation task

NeuroImage ◽

10.1016/j.neuroimage.2018.05.029 ◽

2018 ◽

Vol 178 ◽

pp. 92-103 ◽

Cited By ~ 7

Author(s):

Yi Pu ◽

Brian R. Cornwell ◽

Douglas Cheyne ◽

Blake W. Johnson

Keyword(s):

Gamma Activity ◽

Virtual Navigation ◽

Navigation Task ◽

Human Hippocampus ◽

Rest Periods ◽

High Gamma

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High-gamma activity in an attention network predicts individual differences in elderly adults' behavioral performance

NeuroImage ◽

10.1016/j.neuroimage.2014.06.037 ◽

2014 ◽

Vol 100 ◽

pp. 290-300 ◽

Cited By ~ 10

Author(s):

Yoritaka Akimoto ◽

Takayuki Nozawa ◽

Akitake Kanno ◽

Mizuki Ihara ◽

Takakuni Goto ◽

...

Keyword(s):

Individual Differences ◽

Gamma Activity ◽

Behavioral Performance ◽

Elderly Adults ◽

Attention Network ◽

High Gamma

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Differentiation of speech-induced artifacts from physiological high gamma activity in intracranial recordings

10.1101/2021.04.26.441553 ◽

2021 ◽

Author(s):

Alan Bush ◽

Anna Chrabaszcz ◽

Victoria Peterson ◽

Varun Saravanan ◽

Christina Dastolfo-Hromack ◽

...

Keyword(s):

Speech Production ◽

Field Potential ◽

Vibration Sensor ◽

Gamma Activity ◽

Time Frequency ◽

Related Data ◽

Syllable Repetition ◽

Stereotactic Frame ◽

High Gamma ◽

Intracranial Recordings

AbstractThere is great interest in identifying the neurophysiological underpinnings of speech production. Deep brain stimulation (DBS) surgery is unique in that it allows intracranial recordings from both cortical and subcortical regions in patients who are awake and speaking. The quality of these recordings, however, may be affected to various degrees by mechanical forces resulting from speech itself. Here we describe the presence of speech-induced artifacts in local-field potential (LFP) recordings obtained from mapping electrodes, DBS leads, and cortical electrodes. In addition to expected physiological increases in high gamma (60-200 Hz) activity during speech production, time-frequency analysis in many channels revealed a narrowband gamma component that exhibited a pattern similar to that observed in the speech audio spectrogram. This component was present to different degrees in multiple types of neural recordings. We show that this component tracks the fundamental frequency of the participant’s voice, correlates with the power spectrum of speech and has coherence with the produced speech audio. A vibration sensor attached to the stereotactic frame recorded speech-induced vibrations with the same pattern observed in the LFPs. No corresponding component was identified in any neural channel during the listening epoch of a syllable repetition task. These observations demonstrate how speech-induced vibrations can create artifacts in the primary frequency band of interest. Identifying and accounting for these artifacts is crucial for establishing the validity and reproducibility of speech-related data obtained from intracranial recordings during DBS surgery.

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Forebrain Acetylcholine Modulates Isoflurane and Ketamine Anesthesia in Adult Mice

Anesthesiology ◽

10.1097/aln.0000000000003713 ◽

2021 ◽

Vol 134 (4) ◽

pp. 588-606 ◽

Cited By ~ 1

Author(s):

L. Stan Leung ◽

Liangwei Chu ◽

Marco A. M. Prado ◽

Vania F. Prado

Keyword(s):

Interaction Effect ◽

Gamma Activity ◽

Wild Type ◽

Male Adult ◽

Adult Mice ◽

Loss Of Righting Reflex ◽

High Gamma ◽

Ketamine Anesthesia ◽

Gamma Power ◽

Righting Reflex

Background Cholinergic drugs are known to modulate general anesthesia, but anesthesia responses in acetylcholine-deficient mice have not been studied. It was hypothesized that mice with genetic deficiency of forebrain acetylcholine show increased anesthetic sensitivity to isoflurane and ketamine and decreased gamma-frequency brain activity. Methods Male adult mice with heterozygous knockdown of vesicular acetylcholine transporter in the brain or homozygous knockout of the transporter in the basal forebrain were compared with wild-type mice. Hippocampal and frontal cortical electrographic activity and righting reflex were studied in response to isoflurane and ketamine doses. Results The loss-of-righting-reflex dose for isoflurane was lower in knockout (mean ± SD, 0.76 ± 0.08%, n = 18, P = 0.005) but not knockdown (0.78 ± 0.07%, n = 24, P = 0.021), as compared to wild-type mice (0.83 ± 0.07%, n = 23), using a significance criterion of P = 0.017 for three planned comparisons. Loss-of-righting-reflex dose for ketamine was lower in knockout (144 ± 39 mg/kg, n = 14, P = 0.006) but not knockdown (162 ± 32 mg/kg, n = 20, P = 0.602) as compared to wild-type mice (168 ± 24 mg/kg, n = 21). Hippocampal high-gamma (63 to 100 Hz) power after isoflurane was significantly lower in knockout and knockdown mice compared to wild-type mice (isoflurane-dose and mouse-group interaction effect, F[8,56] = 2.87, P = 0.010; n = 5 to 6 mice per group). Hippocampal high-gamma power after ketamine was significantly lower in both knockout and knockdown mice when compared to wild-type mice (interaction effect F[2,13] = 6.06, P = 0.014). The change in frontal cortical gamma power with isoflurane or ketamine was not statistically different among knockout, knockdown, and wild-type mice. Conclusions These findings suggest that forebrain cholinergic neurons modulate behavioral sensitivity and hippocampal gamma activity during isoflurane and ketamine anesthesia. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

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