Kamin Kim1, Amber Schedlbauer2, Matthew Rollo1, Suganya Karunakaran1, Arne D Ekstrom3, Nitin Tandon4. 1. Department of Neurosurgery, University of Texas Health Science Center, 6431 Fannin Street, Houston, TX, 77030, USA. 2. Neuroscience Graduate Program, University of California Davis, 1544 Newton Court, Davis, CA 95616, USA. 3. Department of Psychology, University of California Davis, 135 Young Hall, One Shields Avenue, Davis, CA 95616, USA; Center for Neuroscience, University of California Davis, 1544 Newton Court, Davis, CA 95616, USA. Electronic address: adekstrom@ucdavis.edu. 4. Department of Neurosurgery, University of Texas Health Science Center, 6431 Fannin Street, Houston, TX, 77030, USA. Electronic address: Nitin.Tandon@uth.tmc.edu.
Abstract
BACKGROUND: Direct brain stimulation via electrodes implanted for intracranial electroencephalography (iEEG) permits the modulation of endogenous electrical signals with significantly greater spatial and temporal specificity than non-invasive approaches. It also allows for the stimulation of deep brain structures important to memory, such as the hippocampus, that are difficult, if not impossible, to target non-invasively. Direct stimulation studies of these deep memory structures, though, have produced mixed results, with some reporting improvement, some impairment, and others, no consistent changes. OBJECTIVE/HYPOTHESIS: We hypothesize that to modulate cognitive function using brain stimulation, it is essential to modulate connected nodes comprising a network, rather than just alter local activity. METHODS: iEEG data collected while patients performed a spatiotemporal memory retrieval task were used to map frequency-specific, coherent oscillatory activity between different brain regions associated with successful memory retrieval. We used these to identify two target nodes that exhibited selectively stronger coupling for spatial vs. temporal retrieval. In a subsequent session, electrical stimulation - theta-bursts with a fixed phase-lag (0° or 180°) - was applied to the two target regions while patients performed spatiotemporal retrieval. RESULTS: Stimulation selectively impaired spatial retrieval while not affecting temporal retrieval, and this selective impairment was associated with theta decoupling of the spatial retrieval network. CONCLUSION: These findings suggest that stimulating tightly connected nodes in a functional network at the appropriate phase-lag may effectively modulate the network function, and while in this case it impaired memory processes, it sets a foundation for further network-based perturbation studies.
BACKGROUND: Direct brain stimulation via electrodes implanted for intracranial electroencephalography (iEEG) permits the modulation of endogenous electrical signals with significantly greater spatial and temporal specificity than non-invasive approaches. It also allows for the stimulation of deep brain structures important to memory, such as the hippocampus, that are difficult, if not impossible, to target non-invasively. Direct stimulation studies of these deep memory structures, though, have produced mixed results, with some reporting improvement, some impairment, and others, no consistent changes. OBJECTIVE/HYPOTHESIS: We hypothesize that to modulate cognitive function using brain stimulation, it is essential to modulate connected nodes comprising a network, rather than just alter local activity. METHODS: iEEG data collected while patients performed a spatiotemporal memory retrieval task were used to map frequency-specific, coherent oscillatory activity between different brain regions associated with successful memory retrieval. We used these to identify two target nodes that exhibited selectively stronger coupling for spatial vs. temporal retrieval. In a subsequent session, electrical stimulation - theta-bursts with a fixed phase-lag (0° or 180°) - was applied to the two target regions while patients performed spatiotemporal retrieval. RESULTS: Stimulation selectively impaired spatial retrieval while not affecting temporal retrieval, and this selective impairment was associated with theta decoupling of the spatial retrieval network. CONCLUSION: These findings suggest that stimulating tightly connected nodes in a functional network at the appropriate phase-lag may effectively modulate the network function, and while in this case it impaired memory processes, it sets a foundation for further network-based perturbation studies.
Authors: Mohamad Z Koubeissi; Emine Kahriman; Tanvir U Syed; Jonathan Miller; Dominique M Durand Journal: Ann Neurol Date: 2013-09-04 Impact factor: 10.422
Authors: Jonathan K Kleen; Rod C Scott; Gregory L Holmes; David W Roberts; Melissa M Rundle; Markus Testorf; Pierre-Pascal Lenck-Santini; Barbara C Jobst Journal: Neurology Date: 2013-05-17 Impact factor: 9.910
Authors: Joshua Jacobs; Jonathan Miller; Sang Ah Lee; Tom Coffey; Andrew J Watrous; Michael R Sperling; Ashwini Sharan; Gregory Worrell; Brent Berry; Bradley Lega; Barbara C Jobst; Kathryn Davis; Robert E Gross; Sameer A Sheth; Youssef Ezzyat; Sandhitsu R Das; Joel Stein; Richard Gorniak; Michael J Kahana; Daniel S Rizzuto Journal: Neuron Date: 2016-12-07 Impact factor: 17.173
Authors: Jennifer Stiso; Ankit N Khambhati; Tommaso Menara; Ari E Kahn; Joel M Stein; Sandihitsu R Das; Richard Gorniak; Joseph Tracy; Brian Litt; Kathryn A Davis; Fabio Pasqualetti; Timothy H Lucas; Danielle S Bassett Journal: Cell Rep Date: 2019-09-03 Impact factor: 9.423
Authors: Michele Bianchi; Anna De Salvo; Maria Asplund; Stefano Carli; Michele Di Lauro; Andreas Schulze-Bonhage; Thomas Stieglitz; Luciano Fadiga; Fabio Biscarini Journal: Adv Sci (Weinh) Date: 2022-02-21 Impact factor: 17.521