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4. Ripple oscillations in the left temporal neocortex are associated with impaired verbal episodic memory encoding

Author

Waldman, Zachary J., Camarillo-Rodriguez, Liliana, Chervenova, Inna, Berry, Brent, Shimamoto, Shoichi, Elahian, Bahareh, Kucewicz, Michal, Ganne, Chaitanya, He, Xiao-Song, Davis, Leon A., Stein, Joel, Das, Sandhitsu, Gorniak, Richard, Sharan, Ashwini D., Gross, Robert, Inman, Cory S., Lega, Bradley C., Zaghloul, Kareem, Jobst, Barbara C., Davis, Katheryn A., Wanda, Paul, Khadjevand, Mehraneh, Tracy, Joseph, Rizzuto, Daniel S., Worrell, Gregory, Sperling, Michael, and Weiss, Shennan A.

Subjects
Quantitative Biology - Neurons and Cognition
Abstract

Background: We sought to determine if ripple oscillations (80-120Hz), detected in intracranial EEG (iEEG) recordings of epilepsy patients, correlate with an enhancement or disruption of verbal episodic memory encoding. Methods: We defined ripple and spike events in depth iEEG recordings during list learning in 107 patients with focal epilepsy. We used logistic regression models (LRMs) to investigate the relationship between the occurrence of ripple and spike events during word presentation and the odds of successful word recall following a distractor epoch, and included the seizure onset zone (SOZ) as a covariate in the LRMs. Results: We detected events during 58,312 word presentation trials from 7,630 unique electrode sites. The probability of ripple on spike (RonS) events was increased in the seizure onset zone (SOZ, p<0.04). In the left temporal neocortex RonS events during word presentation corresponded with a decrease in the odds ratio (OR) of successful recall, however this effect only met significance in the SOZ (OR of word recall 0.71, 95% CI: 0.59-0.85, n=158 events, adaptive Hochberg p<0.01). Ripple on oscillation events (RonO) that occurred in the left temporal neocortex non-SOZ also correlated with decreased odds of successful recall (OR 0.52, 95% CI: 0.34-0.80, n=140, adaptive Hochberg , p<0.01). Spikes and RonS that occurred during word presentation in the left middle temporal gyrus during word presentation correlated with the most significant decrease in the odds of successful recall, irrespective of the location of the SOZ (adaptive Hochberg, p<0.01). Conclusion: Ripples and spikes generated in left temporal neocortex are associated with impaired verbal episodic memory encoding.

Published
2018

5. Functional control of electrophysiological network architecture using direct neurostimulation in humans

Author

Khambhati, Ankit N, Kahn, Ari E, Costantini, Julia, Ezzyat, Youssef, Solomon, Ethan A, Gross, Robert E, Jobst, Barbara C, Sheth, Sameer A, Zaghloul, Kareem A, Worrell, Gregory, Seger, Sarah, Lega, Bradley C, Weiss, Shennan, Sperling, Michael R, Gorniak, Richard, Das, Sandhitsu R, Stein, Joel M, Rizzuto, Daniel S, Kahana, Michael J, Lucas, Timothy H, Davis, Kathryn A, Tracy, Joseph I, and Bassett, Danielle S

Subjects
Biological Psychology, Psychology, Neurosciences, Brain Disorders, Assistive Technology, Bioengineering, Neurological, Neurostimulation, Electrocorticography, Structural controllability, Reconfiguration, Biological psychology
Abstract

Chronically implantable neurostimulation devices are becoming a clinically viable option for treating patients with neurological disease and psychiatric disorders. Neurostimulation offers the ability to probe and manipulate distributed networks of interacting brain areas in dysfunctional circuits. Here, we use tools from network control theory to examine the dynamic reconfiguration of functionally interacting neuronal ensembles during targeted neurostimulation of cortical and subcortical brain structures. By integrating multimodal intracranial recordings and diffusion-weighted imaging from patients with drug-resistant epilepsy, we test hypothesized structural and functional rules that predict altered patterns of synchronized local field potentials. We demonstrate the ability to predictably reconfigure functional interactions depending on stimulation strength and location. Stimulation of areas with structurally weak connections largely modulates the functional hubness of downstream areas and concurrently propels the brain towards more difficult-to-reach dynamical states. By using focal perturbations to bridge large-scale structure, function, and markers of behavior, our findings suggest that stimulation may be tuned to influence different scales of network interactions driving cognition.

Published
2019

11. The effects of direct brain stimulation in humans depend on frequency, amplitude, and white-matter proximity

Author

Mohan, Uma R., Watrous, Andrew J., Miller, Jonathan F., Lega, Bradley C., Sperling, Michael R., Worrell, Gregory A., Gross, Robert E., Zaghloul, Kareem A., Jobst, Barbara C., Davis, Kathryn A., Sheth, Sameer A., Stein, Joel M., Das, Sandhitsu R., Gorniak, Richard, Wanda, Paul A., Rizzuto, Daniel S., Kahana, Michael J., and Jacobs, Joshua

Published
2020
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15. Functional and anatomical connectivity predict brain stimulation’s mnemonic effects

Author

Ezzyat, Youssef, primary, Kragel, James E, additional, Solomon, Ethan A, additional, Lega, Bradley C, additional, Aronson, Joshua P, additional, Jobst, Barbara C, additional, Gross, Robert E, additional, Sperling, Michael R, additional, Worrell, Gregory A, additional, Sheth, Sameer A, additional, Wanda, Paul A, additional, Rizzuto, Daniel S, additional, and Kahana, Michael J, additional

Published
2023
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19. Direct Brain Stimulation Modulates Encoding States and Memory Performance in Humans

Author

Ezzyat, Youssef, Kragel, James E., Burke, John F., Levy, Deborah F., Lyalenko, Anastasia, Wanda, Paul, O’Sullivan, Logan, Hurley, Katherine B., Busygin, Stanislav, Pedisich, Isaac, Sperling, Michael R., Worrell, Gregory A., Kucewicz, Michal T., Davis, Kathryn A., Lucas, Timothy H., Inman, Cory S., Lega, Bradley C., Jobst, Barbara C., Sheth, Sameer A., Zaghloul, Kareem, Jutras, Michael J., Stein, Joel M., Das, Sandhitsu R., Gorniak, Richard, Rizzuto, Daniel S., and Kahana, Michael J.

Published
2017
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25. Features of intracranial interictal epileptiform discharges associated with memory encoding

Author

Quon, Robert J., primary, Camp, Edward J., additional, Meisenhelter, Stephen, additional, Song, Yinchen, additional, Steimel, Sarah A., additional, Testorf, Markus E., additional, Andrew, Angeline S., additional, Gross, Robert E., additional, Lega, Bradley C., additional, Sperling, Michael R., additional, Kahana, Michael J., additional, and Jobst, Barbara C., additional

Published
2021
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28. The effects of direct brain stimulation in humans depend on frequency, amplitude, and white-matter proximity

Author

Mohan, Uma R, Watrous, Andrew J, Miller, Jonathan F, Lega, Bradley C, Sperling, Michael R, Worrell, Gregory A, Gross, Robert E, Zaghloul, Kareem A, Jobst, Barbara C, Davis, Kathryn A, Sheth, Sameer A, Stein, Joel M, Das, Sandhitsu R, Gorniak, MD, Richard, Wanda, Paul A, Rizzuto, Daniel S, Kahana, Michael J, Jacobs, Joshua, Mohan, Uma R, Watrous, Andrew J, Miller, Jonathan F, Lega, Bradley C, Sperling, Michael R, Worrell, Gregory A, Gross, Robert E, Zaghloul, Kareem A, Jobst, Barbara C, Davis, Kathryn A, Sheth, Sameer A, Stein, Joel M, Das, Sandhitsu R, Gorniak, MD, Richard, Wanda, Paul A, Rizzuto, Daniel S, Kahana, Michael J, and Jacobs, Joshua

Abstract

BACKGROUND: Researchers have used direct electrical brain stimulation to treat a range of neurological and psychiatric disorders. However, for brain stimulation to be maximally effective, clinicians and researchers should optimize stimulation parameters according to desired outcomes. OBJECTIVE: The goal of our large-scale study was to comprehensively evaluate the effects of stimulation at different parameters and locations on neuronal activity across the human brain. METHODS: To examine how different kinds of stimulation affect human brain activity, we compared the changes in neuronal activity that resulted from stimulation at a range of frequencies, amplitudes, and locations with direct human brain recordings. We recorded human brain activity directly with electrodes that were implanted in widespread regions across 106 neurosurgical epilepsy patients while systematically stimulating across a range of parameters and locations. RESULTS: Overall, stimulation most often had an inhibitory effect on neuronal activity, consistent with earlier work. When stimulation excited neuronal activity, it most often occurred from high-frequency stimulation. These effects were modulated by the location of the stimulating electrode, with stimulation sites near white matter more likely to cause excitation and sites near gray matter more likely to inhibit neuronal activity. CONCLUSION: By characterizing how different stimulation parameters produced specific neuronal activity patterns on a large scale, our results provide an electrophysiological framework that clinicians and researchers may consider when designing stimulation protocols to cause precisely targeted changes in human brain activity.

Published
2020

30. Interictal Epileptiform Discharges are Task Dependent and are Associated with Lasting Electrocorticographic Changes

Author

Meisenhelter, Stephen, primary, Quon, Robert J, additional, Steimel, Sarah A, additional, Testorf, Markus E, additional, Camp, Edward J, additional, Moein, Payam, additional, Culler, George W, additional, Gross, Robert E, additional, Lega, Bradley C, additional, Sperling, Michael R, additional, Kahana, Michael J, additional, and Jobst, Barbara C, additional

Published
2021
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33. Factors correlated with intracranial interictal epileptiform discharges in refractory epilepsy

Author

Quon, Robert J., primary, Meisenhelter, Stephen, additional, Adamovich‐Zeitlin, Richard H., additional, Song, Yinchen, additional, Steimel, Sarah A., additional, Camp, Edward J., additional, Testorf, Markus E., additional, MacKenzie, Todd A., additional, Gross, Robert E., additional, Lega, Bradley C., additional, Sperling, Michael R., additional, Kahana, Michael J., additional, and Jobst, Barbara C., additional

Published
2020
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39. Risk of seizures induced by intracranial research stimulation: analysis of 770 stimulation sessions

Author

Goldstein, Hannah E, primary, Smith, Elliot H, additional, Gross, Robert E, additional, Jobst, Barbara C, additional, Lega, Bradley C, additional, Sperling, Michael R, additional, Worrell, Gregory A, additional, Zaghloul, Kareem A, additional, Wanda, Paul A, additional, Kahana, Michael J, additional, Rizzuto, Daniel S, additional, Schevon, Catherine A, additional, McKhann, Guy M, additional, and Sheth, Sameer A, additional

Published
2019
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40. The effects of direct brain stimulation in humans depend on frequency, amplitude, and white-matter proximity

Author

Mohan, Uma R., primary, Watrous, Andrew J., additional, Miller, Jonathan F., additional, Lega, Bradley C., additional, Sperling, Michael R., additional, Worrell, Gregory A., additional, Gross, Robert E., additional, Zaghloul, Kareem A., additional, Jobst, Barbara C., additional, Davis, Kathryn A., additional, Sheth, Sameer A., additional, Stein, Joel M., additional, Das, Sandhitsu R., additional, Gorniak, Richard, additional, Wanda, Paul A., additional, Rizzuto, Daniel S., additional, Kahana, Michael J., additional, and Jacobs, Joshua, additional

Published
2019
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42. Risk of Seizures Induced by Intracranial Research Stimulation: Analysis of 770 Stimulation Sessions

Author

Goldstein, Hannah E., primary, Smith, Elliot H., additional, Gross, Robert E., additional, Jobst, Barbara C., additional, Lega, Bradley C., additional, Sperling, Michael R., additional, Worrell, Gregory A., additional, Zaghloul, Kareem A., additional, Wanda, Paul A., additional, Kahana, Michael J., additional, Rizzuto, Daniel S., additional, Schevon, Catherine A., additional, McKhann, Guy M., additional, and Sheth, Sameer A., additional

Published
2019
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44. Neural activity reveals interactions between episodic and semantic memory systems during retrieval.

Author

Weidemann, Christoph T., primary, Kragel, James E., additional, Lega, Bradley C., additional, Worrell, Gregory A., additional, Sperling, Michael R., additional, Sharan, Ashwini D., additional, Jobst, Barbara C., additional, Khadjevand, Fatemeh, additional, Davis, Kathryn A., additional, Wanda, Paul A., additional, Kadel, Allison, additional, Rizzuto, Daniel S., additional, and Kahana, Michael J., additional

Published
2019
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46. Closed-loop stimulation of temporal cortex rescues functional networks and improves memory.

Author

Ezzyat, Youssef, Wanda, Paul A., Levy, Deborah F., Kadel, Allison, Aka, Ada, Pedisich, Isaac, Sperling, Michael R., Sharan, Ashwini, Lega, Bradley C., Burks, Alexis, Gross, Robert E., Inman, Cory S., Jobst, Barbara C., Gorenstein, Mark A., Davis, Kathryn A., Worrell, Gregory A., Kucewicz, Michal T., Stein, Joel M., Gorniak, Richard, Das, Sandhitsu R., Rizzuto, Daniel S., Kahana, Michael J., Ezzyat, Youssef, Wanda, Paul A., Levy, Deborah F., Kadel, Allison, Aka, Ada, Pedisich, Isaac, Sperling, Michael R., Sharan, Ashwini, Lega, Bradley C., Burks, Alexis, Gross, Robert E., Inman, Cory S., Jobst, Barbara C., Gorenstein, Mark A., Davis, Kathryn A., Worrell, Gregory A., Kucewicz, Michal T., Stein, Joel M., Gorniak, Richard, Das, Sandhitsu R., Rizzuto, Daniel S., and Kahana, Michael J.

Abstract

Memory failures are frustrating and often the result of ineffective encoding. One approach to improving memory outcomes is through direct modulation of brain activity with electrical stimulation. Previous efforts, however, have reported inconsistent effects when using open-loop stimulation and often target the hippocampus and medial temporal lobes. Here we use a closed-loop system to monitor and decode neural activity from direct brain recordings in humans. We apply targeted stimulation to lateral temporal cortex and report that this stimulation rescues periods of poor memory encoding. This system also improves later recall, revealing that the lateral temporal cortex is a reliable target for memory enhancement. Taken together, our results suggest that such systems may provide a therapeutic approach for treating memory dysfunction.

Published
2018

47. Factors correlated with intracranial interictal epileptiform discharges in refractory epilepsy.

Author

Quon, Robert J., Meisenhelter, Stephen, Adamovich‐Zeitlin, Richard H., Song, Yinchen, Steimel, Sarah A., Camp, Edward J., Testorf, Markus E., MacKenzie, Todd A., Gross, Robert E., Lega, Bradley C., Sperling, Michael R., Kahana, Michael J., and Jobst, Barbara C.

Subjects
MORNINGNESS-Eveningness Questionnaire, EPILEPSY, PEOPLE with epilepsy, ANTICONVULSANTS, ATTENTION control, EPILEPTIFORM discharges
Abstract

Objective: This study was undertaken to evaluate the influence that subject‐specific factors have on intracranial interictal epileptiform discharge (IED) rates in persons with refractory epilepsy. Methods: One hundred fifty subjects with intracranial electrodes performed multiple sessions of a free recall memory task; this standardized task controlled for subject attention levels. We utilized a dominance analysis to rank the importance of subject‐specific factors based on their relative influence on IED rates. Linear mixed‐effects models were employed to comprehensively examine factors with highly ranked importance. Results: Antiseizure medication (ASM) status, time of testing, and seizure onset zone (SOZ) location were the highest‐ranking factors in terms of their impact on IED rates. The average IED rate of electrodes in SOZs was 34% higher than the average IED rate of electrodes outside of SOZs (non‐SOZ; p <.001). However, non‐SOZ electrodes had similar IED rates regardless of the subject's SOZ location (p =.99). Subjects on older generation (p <.001) and combined generation (p <.001) ASM regimens had significantly lower IED rates relative to the group taking no ASMs; newer generation ASM regimens demonstrated a nonsignificant association with IED rates (p =.13). Of the ASMs included in this study, the following ASMs were associated with significant reductions in IED rates: levetiracetam (p <.001), carbamazepine (p <.001), lacosamide (p =.03), zonisamide (p =.01), lamotrigine (p =.03), phenytoin (p =.03), and topiramate (p =.01). We observed a nonsignificant association between time of testing and IED rates (morning–afternoon p =.15, morning–evening p =.85, afternoon–evening p =.26). Significance: The current study ranks the relative influence that subject‐specific factors have on IED rates and highlights the importance of considering certain factors, such as SOZ location and ASM status, when analyzing IEDs for clinical or research purposes. [ABSTRACT FROM AUTHOR]

Published
2021
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48. Ripple oscillations in the left temporal neocortex are associated with impaired verbal episodic memory encoding

Author

Waldman, Zachary J., primary, Camarillo-Rodriguez, Liliana, additional, Chervenova, Inna, additional, Berry, Brent, additional, Shimamoto, Shoichi, additional, Elahian, Bahareh, additional, Kucewicz, Michal, additional, Ganne, Chaitanya, additional, He, Xiao-Song, additional, Davis, Leon A., additional, Stein, Joel, additional, Das, Sandhitsu, additional, Gorniak, Richard, additional, Sharan, Ashwini D., additional, Gross, Robert, additional, Inman, Cory S., additional, Lega, Bradley C., additional, Zaghloul, Kareem, additional, Jobst, Barbara C., additional, Davis, Katheryn A., additional, Wanda, Paul, additional, Khadjevand, Mehraneh, additional, Tracy, Joseph, additional, Rizzuto, Daniel S., additional, Worrell, Gregory, additional, Sperling, Michael, additional, and Weiss, Shennan A., additional

Published
2018
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49. Predictive control of electrophysiological network architecture using direct, single-node neurostimulation in humans

Author

Khambhati, Ankit N., primary, Kahn, Ari E., additional, Costantini, Julia, additional, Ezzyat, Youssef, additional, Solomon, Ethan A., additional, Gross, Robert E., additional, Jobst, Barbara C., additional, Sheth, Sameer A., additional, Zaghloul, Kareem A., additional, Worrell, Gregory, additional, Seger, Sarah, additional, Lega, Bradley C., additional, Weiss, Shennan, additional, Sperling, Michael R., additional, Gorniak, Richard, additional, Das, Sandhitsu R., additional, Stein, Joel M., additional, Rizzuto, Daniel S., additional, Kahana, Michael J., additional, Lucas, Timothy H., additional, Davis, Kathryn A., additional, Tracy, Joseph I., additional, and Bassett, Danielle S., additional

Published
2018
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50. Closed-loop stimulation of temporal cortex rescues functional networks and improves memory

Author

Ezzyat, Youssef, primary, Wanda, Paul A., additional, Levy, Deborah F., additional, Kadel, Allison, additional, Aka, Ada, additional, Pedisich, Isaac, additional, Sperling, Michael R., additional, Sharan, Ashwini D., additional, Lega, Bradley C., additional, Burks, Alexis, additional, Gross, Robert E., additional, Inman, Cory S., additional, Jobst, Barbara C., additional, Gorenstein, Mark A., additional, Davis, Kathryn A., additional, Worrell, Gregory A., additional, Kucewicz, Michal T., additional, Stein, Joel M., additional, Gorniak, Richard, additional, Das, Sandhitsu R., additional, Rizzuto, Daniel S., additional, and Kahana, Michael J., additional

Published
2018
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