Intracortical dynamics underlying repetitive stimulation predicts changes in network connectivity

AbstractTargeted stimulation can be used to modulate the activity of brain networks. Previously we demonstrated that direct electrical stimulation produces predictable post-stimulation changes in brain excitability. However, understanding the neural dynamics during stimulation and its relationship to post-stimulation effects is limited but critical for treatment optimization. Here, we applied 10Hz direct electrical stimulation across several cortical regions in 14 patients implanted with intracranial electrodes for seizure monitoring. The stimulation train was characterized by a consistent increase in high gamma (70-170Hz) power. Immediately post-train, low-frequency (1-8Hz) power increased, resulting in an evoked response that was highly correlated with the neural response during stimulation. Using two measures of network connectivity, cortico-cortical evoked potentials (indexing effective connectivity) and theta coherence (indexing functional connectivity), we found a stronger response to stimulation in regions that were highly connected to the stimulation site. In these regions, repeated cycles of stimulation trains and rest progressively altered the stimulation response. Finally, after just 2 minutes (10%) of repetitive stimulation, we were able to predict post-stimulation connectivity changes with high discriminability. Taken together, this work reveals a relationship between stimulation dynamics and post-stimulation connectivity changes in humans. Thus, measuring neural activity during stimulation can inform future plasticity-inducing protocols.

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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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Untangling cortico-striatal connectivity and cross-frequency coupling in L-DOPA-induced dyskinesia

10.1101/028027 ◽

2015 ◽

Cited By ~ 1

Author(s):

Jovana Belic ◽

Per Halje ◽

Ulrike Richter ◽

Per Petersson ◽

Jeanette Hellgren Kotaleski

Keyword(s):

Primary Motor Cortex ◽

Effective Connectivity ◽

Spectral Characteristics ◽

Low Frequency ◽

Frequency Range ◽

Gamma Frequency ◽

High Gamma ◽

Freely Behaving ◽

Beta Frequency ◽

Cross Frequency Coupling

We simultaneously recorded local field potentials in the primary motor cortex and sensorimotor striatum in awake, freely behaving, 6-OHDA lesioned hemi-parkinsonian rats in order to study the features directly related to pathological states such as parkinsonian state and levodopa-induced dyskinesia. We analysed the spectral characteristics of the obtained signals and observed that during dyskinesia the most prominent feature was a relative power increase in the high gamma frequency range at around 80 Hz, while for the parkinsonian state it was in the beta frequency range. Here we show that during both pathological states effective connectivity in terms of Granger causality is bidirectional with an accent on the striatal influence on the cortex. In the case of dyskinesia, we also found a high increase in effective connectivity at 80 Hz. In order to further understand the 80- Hz phenomenon, we performed cross-frequency analysis and observed characteristic patterns in the case of dyskinesia but not in the case of the parkinsonian state or the control state. We noted a large decrease in the modulation of the amplitude at 80 Hz by the phase of low frequency oscillations (up to ~10 Hz) across both structures in the case of dyskinesia. This may suggest a lack of coupling between the low frequency activity of the recorded network and the group of neurons active at ~80 Hz.

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Intraoperative mapping of executive function using electrocorticography for patients with low-grade gliomas

Acta Neurochirurgica ◽

10.1007/s00701-020-04646-6 ◽

2020 ◽

Author(s):

Yaara Erez ◽

Moataz Assem ◽

Pedro Coelho ◽

Rafael Romero-Garcia ◽

Mallory Owen ◽

...

Keyword(s):

Electrical Stimulation ◽

Executive Function ◽

Executive Functions ◽

Neural Activity ◽

Task Difficulty ◽

Awake Surgery ◽

Low Grade ◽

Direct Electrical Stimulation ◽

High Gamma ◽

Gamma Power

Abstract Background Intraoperative functional mapping with direct electrical stimulation during awake surgery for patients with diffuse low-grade glioma has been used in recent years to optimize the balance between surgical resection and quality of life following surgery. Mapping of executive functions is particularly challenging because of their complex nature, with only a handful of reports published so far. Here, we propose the recording of neural activity directly from the surface of the brain using electrocorticography to map executive functions and demonstrate its feasibility and potential utility. Methods To track a neural signature of executive function, we recorded neural activity using electrocorticography during awake surgery from the frontal cortex of three patients judged to have an appearance of diffuse low-grade glioma. Based on existing functional magnetic resonance imaging (fMRI) evidence from healthy participants for the recruitment of areas associated with executive function with increased task demands, we employed a task difficulty manipulation in two counting tasks performed intraoperatively. Following surgery, the data were extracted and analyzed offline to identify increases in broadband high-gamma power with increased task difficulty, equivalent to fMRI findings, as a signature of activity related to executive function. Results All three patients performed the tasks well. Data were recorded from five electrode strips, resulting in data from 15 channels overall. Eleven out of the 15 channels (73.3%) showed significant increases in high-gamma power with increased task difficulty, 26.6% of the channels (4/15) showed no change in power, and none of the channels showed power decrease. High-gamma power increases with increased task difficulty were more likely in areas that are within the canonical frontoparietal network template. Conclusions These results are the first step toward developing electrocorticography as a tool for mapping of executive function complementarily to direct electrical stimulation to guide resection. Further studies are required to establish this approach for clinical use.

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Perceptions of low‐frequency stimuli induced by direct electrical stimulation at the cochlea

The Journal of the Acoustical Society of America ◽

10.1121/1.2004735 ◽

1980 ◽

Vol 68 (S1) ◽

pp. S44-S44

Author(s):

Bradly J. Edgerton ◽

William F. House ◽

Karen J. Doyle

Keyword(s):

Electrical Stimulation ◽

Low Frequency ◽

Direct Electrical Stimulation

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Intraoperative mapping of executive function using electrocorticography for patients with low-grade gliomas

10.31219/osf.io/gy84r ◽

2020 ◽

Author(s):

Yaara Erez ◽

Moataz Assem ◽

Pedro Coelho ◽

Rafael Romero-Garcia ◽

Mallory Owen ◽

...

Keyword(s):

Electrical Stimulation ◽

Executive Function ◽

Executive Functions ◽

Neural Activity ◽

Task Difficulty ◽

Awake Surgery ◽

Low Grade ◽

Direct Electrical Stimulation ◽

High Gamma ◽

Gamma Power

Background: Intraoperative functional mapping with direct electrical stimulation during awake surgery for patients with diffuse low-grade glioma has been used in recent years to optimize the balance between surgical resection and quality of life following surgery. Mapping of executive functions is particularly challenging because their complex nature, with only a handful of reports so far. Here, we propose recording of neural activity directly from the surface of the brain using electrocorticography to map executive functions and demonstrate its feasibility and potential utility.Methods: To track a neural signature of executive function, we recorded neural activity using electrocorticography during awake surgery from the frontal cortex of three patients judged to have an appearance of diffuse low-grade glioma. Based on existing functional magnetic resonance imaging (fMRI) evidence from healthy participants for the recruitment of areas associated with executive function with increased task demands, we employed a task difficulty manipulation in two counting tasks performed intraoperatively. Following surgery, the data were extracted and analyzed offline to identify increases in broadband high-gamma power with increased task difficulty, equivalent to fMRI findings, as a signature of activity related to executive function.Results: All three patients performed the tasks well. Data were recorded from five electrode strips, resulting in data from 15 channels overall. 73.3% of the channels (11/15) showed significant increases in high-gamma power with increased task difficulty, 26.6% channels (4/15) showed no change in power, and none of the channels showed power decrease. High-gamma power increases with increased task difficulty were more likely in areas that are within the canonical frontoparietal network template.Conclusions: These results are the first step towards developing electrocorticography as a tool for mapping of executive function complementarily to direct electrical stimulation to guide resection. Further studies and clinical trials are required to establish this approach for clinical use.

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Transient hypoxemia induced by cortical electrical stimulation

Neurology ◽

10.1212/wnl.0000000000009497 ◽

2020 ◽

Vol 94 (22) ◽

pp. e2323-e2336

Author(s):

Marine Loizon ◽

Philippe Ryvlin ◽

Benoit Chatard ◽

Julien Jung ◽

Romain Bouet ◽

...

Keyword(s):

Electrical Stimulation ◽

Primary Outcome ◽

Focal Epilepsy ◽

Direct Electrical Stimulation ◽

Limbic Structures ◽

Individual Effects ◽

Cortical Electrical Stimulation ◽

Eeg Recordings ◽

Cortical Regions ◽

Stimulation Of

ObjectiveTo identify which cortical regions are associated with direct electrical stimulation (DES)–induced alteration of breathing significant enough to impair pulse oximetry (SpO2).MethodsEvolution of SpO2 after 1,352 DES was analyzed in 75 patients with refractory focal epilepsy who underwent stereo-EEG recordings. For each DES, we assessed the change in SpO2 from 30 seconds prior to DES onset to 120 seconds following the end of the DES. The primary outcome was occurrence of stimulation-induced transient hypoxemia as defined by decrease of SpO2 ≥5% within 60 seconds after stimulation onset as compared to pre-DES SpO2 or SpO2 nadir <90% during at least 5 seconds. Localization of the stimulated contacts was defined according to MarsAtlas brain parcellation and Freesurfer segmentation.ResultsA stimulation-induced transient hypoxemia was observed after 16 DES (1.2%) in 10 patients (13%), including 6 in whom SpO2 nadir was <90%. Among these 16 DES, 7 (44%) were localized within the perisylvian cortex. After correction for individual effects and the varying number of DES contributed by each person, significant decrease of SpO2 was significantly associated with the localization of DES (p = 0.019).ConclusionThough rare, a significant decrease of SpO2 could be elicited by cortical direct electrical stimulation outside the temporo-limbic structures, most commonly after stimulation of the perisylvian cortex.

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Deep Brain Stimulation of the Posterior Insula in Chronic Pain: A Theoretical Framework

Brain Sciences ◽

10.3390/brainsci11050639 ◽

2021 ◽

Vol 11 (5) ◽

pp. 639

Author(s):

David Bergeron ◽

Sami Obaid ◽

Marie-Pierre Fournier-Gosselin ◽

Alain Bouthillier ◽

Dang Khoa Nguyen

Keyword(s):

Chronic Pain ◽

Electrical Stimulation ◽

Deep Brain Stimulation ◽

Brain Stimulation ◽

High Frequency ◽

Brain Lesion ◽

Low Frequency ◽

Posterior Insula ◽

Deep Brain ◽

Stimulation Of

Introduction: To date, clinical trials of deep brain stimulation (DBS) for refractory chronic pain have yielded unsatisfying results. Recent evidence suggests that the posterior insula may represent a promising DBS target for this indication. Methods: We present a narrative review highlighting the theoretical basis of posterior insula DBS in patients with chronic pain. Results: Neuroanatomical studies identified the posterior insula as an important cortical relay center for pain and interoception. Intracranial neuronal recordings showed that the earliest response to painful laser stimulation occurs in the posterior insula. The posterior insula is one of the only regions in the brain whose low-frequency electrical stimulation can elicit painful sensations. Most chronic pain syndromes, such as fibromyalgia, had abnormal functional connectivity of the posterior insula on functional imaging. Finally, preliminary results indicated that high-frequency electrical stimulation of the posterior insula can acutely increase pain thresholds. Conclusion: In light of the converging evidence from neuroanatomical, brain lesion, neuroimaging, and intracranial recording and stimulation as well as non-invasive stimulation studies, it appears that the insula is a critical hub for central integration and processing of painful stimuli, whose high-frequency electrical stimulation has the potential to relieve patients from the sensory and affective burden of chronic pain.

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