1
|
Massimini M, Corbetta M, Sanchez-Vives MV, Andrillon T, Deco G, Rosanova M, Sarasso S. Sleep-like cortical dynamics during wakefulness and their network effects following brain injury. Nat Commun 2024; 15:7207. [PMID: 39174560 PMCID: PMC11341729 DOI: 10.1038/s41467-024-51586-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 08/07/2024] [Indexed: 08/24/2024] Open
Abstract
By connecting old and recent notions, different spatial scales, and research domains, we introduce a novel framework on the consequences of brain injury focusing on a key role of slow waves. We argue that the long-standing finding of EEG slow waves after brain injury reflects the intrusion of sleep-like cortical dynamics during wakefulness; we illustrate how these dynamics are generated and how they can lead to functional network disruption and behavioral impairment. Finally, we outline a scenario whereby post-injury slow waves can be modulated to reawaken parts of the brain that have fallen asleep to optimize rehabilitation strategies and promote recovery.
Collapse
Grants
- The authors thank Dr Ezequiel Mikulan, Dr Silvia Casarotto, Dr Andrea Pigorini, Dr Simone Russo, and Dr Pilleriin Sikka for their help and comments on the manuscript draft and illustrations. This work was financially supported by the following entities: ERC-2022-SYG Grant number 101071900 Neurological Mechanisms of Injury and Sleep-like Cellular Dynamics (NEMESIS); Italian National Recovery and Resilience Plan (NRRP), M4C2, funded by the European Union - NextGenerationEU (Project IR0000011, CUP B51E22000150006, “EBRAINS-Italy”); European Union’s Horizon 2020 Framework Program for Research and Innovation under the Specific Grant Agreement No.945539 (Human Brain Project SGA3); Tiny Blue Dot Foundation; Canadian Institute for Advanced Research (CIFAR), Canada; Italian Ministry for Universities and Research (PRIN 2022); Fondazione Regionale per la Ricerca Biomedica (Regione Lombardia), Project ERAPERMED2019–101, GA 779282; CORTICOMOD PID2020-112947RB-I00 financed by MCIN/ AEI /10.13039/501100011033; Fondazione Cassa di Risparmio di Padova e Rovigo (CARIPARO) Grant Agreement number 55403; Ministry of Health, Italy (RF-2008 -12366899) Brain connectivity measured with high-density electroencephalography: a novel neurodiagnostic tool for stroke- NEUROCONN; BIAL foundation grant (Grant Agreement number 361/18); H2020 European School of Network Neuroscience (euSNN); H2020 Visionary Nature Based Actions For Heath, Wellbeing & Resilience in Cities (VARCITIES); Ministry of Health Italy (RF-2019-12369300): Eye-movement dynamics during free viewing as biomarker for assessment of visuospatial functions and for closed-loop rehabilitation in stroke (EYEMOVINSTROKE).
Collapse
Affiliation(s)
- Marcello Massimini
- Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy.
- IRCCS Fondazione Don Carlo Gnocchi ONLUS, Milan, Italy.
| | - Maurizio Corbetta
- Department of Neuroscience and Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
- Veneto Institute of Molecular Medicine (VIMM), Padova, Italy
| | - Maria V Sanchez-Vives
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
- Institució Catalana de la Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Thomas Andrillon
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Mov'it team, Inserm, CNRS, Paris, France
- Monash Centre for Consciousness and Contemplative Studies, Faculty of Arts, Monash University, Melbourne, VIC, Australia
| | - Gustavo Deco
- Institució Catalana de la Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Department of Information and Communication Technologies, Universitat Pompeu Fabra, Center for Brain and Cognition, Computational Neuroscience Group, Barcelona, Spain
| | - Mario Rosanova
- Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy
| | - Simone Sarasso
- Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy
| |
Collapse
|
2
|
Vaz PN, Antunes F, Mendes EMAM, Felix LB. Automated detection of auditory response: non-detection stopping criterion and repeatability studies for multichannel EEG. Comput Methods Biomech Biomed Engin 2024; 27:1150-1160. [PMID: 37417665 DOI: 10.1080/10255842.2023.2232071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 06/27/2023] [Indexed: 07/08/2023]
Abstract
An Auditory Steady-State Response (ASSR) is a valuable tool for determining auditory thresholds in individuals who are either unable or unwilling to cooperate with conventional behavioral testing methods. This study proposes a sequential test technique for automatic detection of ASSRs, incorporating a non-detection stopping criterion. The electrophysiological thresholds of a normal hearing volunteer were established using data collected from multichannel EEG signals. The detection probabilities and critical values were obtained via Monte Carlo simulations. Remarkably, application of the non-detection stopping criterion resulted in a 60% reduction in exam time in the absence of a response. These findings clearly demonstrate the significant potential of the sequential test in enhancing the performance of automatic audiometry.
Collapse
Affiliation(s)
- Patrícia Nogueira Vaz
- Graduate Program in Electrical Engineering, Federal University of Minas Gerais, Belo Horizonte, MG CEP, Brazil
| | - Felipe Antunes
- Federal Institute of Education, Science and Technology of Minas Gerais, Ipatinga, MG CEP, Brazil
| | | | - Leonardo Bonato Felix
- Graduate Program in Electrical Engineering, Federal University of Minas Gerais, Belo Horizonte, MG CEP, Brazil
- Department of Electrical Engineering, Federal University of Viçosa, Viçosa, MG CEP, Brazil
| |
Collapse
|
3
|
Tankus A, Stern E, Klein G, Kaptzon N, Nash L, Marziano T, Shamia O, Gurevitch G, Bergman L, Goldstein L, Fahoum F, Strauss I. A Speech Neuroprosthesis in the Frontal Lobe and Hippocampus: Decoding High-Frequency Activity into Phonemes. Neurosurgery 2024:00006123-990000000-01250. [PMID: 38934637 DOI: 10.1227/neu.0000000000003068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 05/05/2024] [Indexed: 06/28/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Loss of speech due to injury or disease is devastating. Here, we report a novel speech neuroprosthesis that artificially articulates building blocks of speech based on high-frequency activity in brain areas never harnessed for a neuroprosthesis before: anterior cingulate and orbitofrontal cortices, and hippocampus. METHODS A 37-year-old male neurosurgical epilepsy patient with intact speech, implanted with depth electrodes for clinical reasons only, silently controlled the neuroprosthesis almost immediately and in a natural way to voluntarily produce 2 vowel sounds. RESULTS During the first set of trials, the participant made the neuroprosthesis produce the different vowel sounds artificially with 85% accuracy. In the following trials, performance improved consistently, which may be attributed to neuroplasticity. We show that a neuroprosthesis trained on overt speech data may be controlled silently. CONCLUSION This may open the way for a novel strategy of neuroprosthesis implantation at earlier disease stages (eg, amyotrophic lateral sclerosis), while speech is intact, for improved training that still allows silent control at later stages. The results demonstrate clinical feasibility of direct decoding of high-frequency activity that includes spiking activity in the aforementioned areas for silent production of phonemes that may serve as a part of a neuroprosthesis for replacing lost speech control pathways.
Collapse
Affiliation(s)
- Ariel Tankus
- Functional Neurosurgery Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Department of Neurology and Neurosurgery, School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Einat Stern
- Department of Neurology and Neurosurgery, School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Guy Klein
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv, Israel
| | - Nufar Kaptzon
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv, Israel
| | - Lilac Nash
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv, Israel
| | - Tal Marziano
- School of Electrical Engineering, Iby and Aladar Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Omer Shamia
- School of Electrical Engineering, Iby and Aladar Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Guy Gurevitch
- Sagol Brain Institute, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Lottem Bergman
- Functional Neurosurgery Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Lilach Goldstein
- Department of Neurology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Firas Fahoum
- Department of Neurology and Neurosurgery, School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Department of Neurology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Ido Strauss
- Functional Neurosurgery Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Department of Neurology and Neurosurgery, School of Medicine, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
4
|
Mao R, Cavelli ML, Findlay G, Driessen K, Peterson MJ, Marshall W, Tononi G, Cirelli C. Behavioral and cortical arousal from sleep, muscimol-induced coma, and anesthesia by direct optogenetic stimulation of cortical neurons. iScience 2024; 27:109919. [PMID: 38812551 PMCID: PMC11134913 DOI: 10.1016/j.isci.2024.109919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 11/28/2023] [Accepted: 05/03/2024] [Indexed: 05/31/2024] Open
Abstract
The cerebral cortex is widely considered part of the neural substrate of consciousness, but direct causal evidence is missing. Here, we tested in mice whether optogenetic activation of cortical neurons in posterior parietal cortex (PtA) or medial prefrontal cortex (mPFC) is sufficient for arousal from three behavioral states characterized by progressively deeper unresponsiveness: sleep, a coma-like state induced by muscimol injection in the midbrain, and deep sevoflurane-dexmedetomidine anesthesia. We find that cortical stimulation always awakens the mice from both NREM sleep and REM sleep, with PtA requiring weaker/shorter light pulses than mPFC. Moreover, in most cases light pulses produce both cortical activation (decrease in low frequencies) and behavioral arousal (recovery of the righting reflex) from brainstem coma, as well as cortical activation from anesthesia. These findings provide evidence that direct activation of cortical neurons is sufficient for behavioral and/or cortical arousal from sleep, brainstem coma, and anesthesia.
Collapse
Affiliation(s)
- Rong Mao
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI 53719, USA
| | - Matias Lorenzo Cavelli
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
- Departamento de Fisiología de Facultad de Medicina, Universidad de la República, Montevideo 11800, Uruguay
| | - Graham Findlay
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI 53719, USA
| | - Kort Driessen
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI 53719, USA
| | - Michael J. Peterson
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
| | - William Marshall
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
- Department of Mathematics and Statistics, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Giulio Tononi
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
| | - Chiara Cirelli
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
| |
Collapse
|
5
|
Bressler S, Neely R, Yost RM, Wang D. A randomized controlled trial of alpha phase-locked auditory stimulation to treat symptoms of sleep onset insomnia. Sci Rep 2024; 14:13039. [PMID: 38844793 PMCID: PMC11156862 DOI: 10.1038/s41598-024-63385-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 05/28/2024] [Indexed: 06/09/2024] Open
Abstract
Sleep onset insomnia is a pervasive problem that contributes significantly to the poor health outcomes associated with insufficient sleep. Auditory stimuli phase-locked to slow-wave sleep oscillations have been shown to augment deep sleep, but it is unknown whether a similar approach can be used to accelerate sleep onset. The present randomized controlled crossover trial enrolled adults with objectively verified sleep onset latencies (SOLs) greater than 30 min to test the effect of auditory stimuli delivered at specific phases of participants' alpha oscillations prior to sleep onset. During the intervention week, participants wore an electroencephalogram (EEG)-enabled headband that delivered acoustic pulses timed to arrive anti-phase with alpha for 30 min (Stimulation). During the Sham week, the headband silently recorded EEG. The primary outcome was SOL determined by blinded scoring of EEG records. For the 21 subjects included in the analyses, stimulation had a significant effect on SOL according to a linear mixed effects model (p = 0.0019), and weekly average SOL decreased by 10.5 ± 15.9 min (29.3 ± 44.4%). These data suggest that phase-locked acoustic stimulation can be a viable alternative to pharmaceuticals to accelerate sleep onset in individuals with prolonged sleep onset latencies. Trial Registration: This trial was first registered on clinicaltrials.gov on 24/02/2023 under the name Sounds Locked to ElectroEncephalogram Phase For the Acceleration of Sleep Onset Time (SLEEPFAST), and assigned registry number NCT05743114.
Collapse
Affiliation(s)
- Scott Bressler
- Elemind Technologies, Inc., Cambridge, MA, USA
- Science and Research, Elemind Technologies, Inc., Cambridge, MA, 02139, USA
| | - Ryan Neely
- Elemind Technologies, Inc., Cambridge, MA, USA.
- Science and Research, Elemind Technologies, Inc., Cambridge, MA, 02139, USA.
| | - Ryan M Yost
- Elemind Technologies, Inc., Cambridge, MA, USA
- Science and Research, Elemind Technologies, Inc., Cambridge, MA, 02139, USA
| | - David Wang
- Elemind Technologies, Inc., Cambridge, MA, USA
| |
Collapse
|
6
|
Tononi G, Boly M, Cirelli C. Consciousness and sleep. Neuron 2024; 112:1568-1594. [PMID: 38697113 PMCID: PMC11105109 DOI: 10.1016/j.neuron.2024.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/04/2024] [Accepted: 04/10/2024] [Indexed: 05/04/2024]
Abstract
Sleep is a universal, essential biological process. It is also an invaluable window on consciousness. It tells us that consciousness can be lost but also that it can be regained, in all its richness, when we are disconnected from the environment and unable to reflect. By considering the neurophysiological differences between dreaming and dreamless sleep, we can learn about the substrate of consciousness and understand why it vanishes. We also learn that the ongoing state of the substrate of consciousness determines the way each experience feels regardless of how it is triggered-endogenously or exogenously. Dreaming consciousness is also a window on sleep and its functions. Dreams tell us that the sleeping brain is remarkably lively, recombining intrinsic activation patterns from a vast repertoire, freed from the requirements of ongoing behavior and cognitive control.
Collapse
Affiliation(s)
- Giulio Tononi
- Department of Psychiatry, University of Wisconsin, Madison, WI 53719, USA.
| | - Melanie Boly
- Department of Neurology, University of Wisconsin, Madison, WI 53719, USA
| | - Chiara Cirelli
- Department of Psychiatry, University of Wisconsin, Madison, WI 53719, USA
| |
Collapse
|
7
|
Taguchi T, Kitazono J, Sasai S, Oizumi M. Association of bidirectional network cores in the brain with conscious perception and cognition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.30.591001. [PMID: 38746271 PMCID: PMC11092575 DOI: 10.1101/2024.04.30.591001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
The brain comprises a complex network of interacting regions. To understand the roles and mechanisms of this complex network, its structural features related to specific cognitive functions need to be elucidated. Among such relationships, recent developments in neuroscience highlight the link between network bidirectionality and conscious perception. Given the essential roles of both feedforward and feedback signals in conscious perception, it is surmised that subnetworks with bidirectional interactions are critical. However, the link between such subnetworks and conscious perception remains unclear due to the network's complexity. In this study, we propose a framework for extracting subnetworks with strong bidirectional interactions-termed the "cores" of a network-from brain activity. We applied this framework to resting-state and task-based fMRI data to identify regions forming strongly bidirectional cores. We then explored the association of these cores with conscious perception and cognitive functions. The central cores predominantly included cerebral cortical regions, which are crucial for conscious perception, rather than subcortical regions. Furthermore, the cores were composed of previously reported regions in which electrical stimulation altered conscious perception. These results suggest a link between the bidirectional cores and conscious perception. A meta-analysis and comparison of the core structure with a cortical functional connectivity gradient suggested that the central cores were related to lower-order sensorimotor functions. An ablation study emphasized the importance of incorporating bidirectionality, not merely interaction strength for these outcomes. The proposed framework provides novel insight into the roles of network cores with strong bidirectional interactions in conscious perception and lower-order sensorimotor functions.
Collapse
Affiliation(s)
- Tomoya Taguchi
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Jun Kitazono
- Graduate School of Data Science, Yokohama City University, Kanagawa, Japan
| | | | - Masafumi Oizumi
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
8
|
Ahveninen J, Lee HJ, Yu HY, Lee CC, Chou CC, Ahlfors SP, Kuo WJ, Jääskeläinen IP, Lin FH. Visual Stimuli Modulate Local Field Potentials But Drive No High-Frequency Activity in Human Auditory Cortex. J Neurosci 2024; 44:e0890232023. [PMID: 38129133 PMCID: PMC10869150 DOI: 10.1523/jneurosci.0890-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 11/06/2023] [Accepted: 11/07/2023] [Indexed: 12/23/2023] Open
Abstract
Neuroimaging studies suggest cross-sensory visual influences in human auditory cortices (ACs). Whether these influences reflect active visual processing in human ACs, which drives neuronal firing and concurrent broadband high-frequency activity (BHFA; >70 Hz), or whether they merely modulate sound processing is still debatable. Here, we presented auditory, visual, and audiovisual stimuli to 16 participants (7 women, 9 men) with stereo-EEG depth electrodes implanted near ACs for presurgical monitoring. Anatomically normalized group analyses were facilitated by inverse modeling of intracranial source currents. Analyses of intracranial event-related potentials (iERPs) suggested cross-sensory responses to visual stimuli in ACs, which lagged the earliest auditory responses by several tens of milliseconds. Visual stimuli also modulated the phase of intrinsic low-frequency oscillations and triggered 15-30 Hz event-related desynchronization in ACs. However, BHFA, a putative correlate of neuronal firing, was not significantly increased in ACs after visual stimuli, not even when they coincided with auditory stimuli. Intracranial recordings demonstrate cross-sensory modulations, but no indication of active visual processing in human ACs.
Collapse
Affiliation(s)
- Jyrki Ahveninen
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts 02129
- Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Hsin-Ju Lee
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario M4N 3M5, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Hsiang-Yu Yu
- Department of Epilepsy, Neurological Institute, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
| | - Cheng-Chia Lee
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Chien-Chen Chou
- Department of Epilepsy, Neurological Institute, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
| | - Seppo P Ahlfors
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts 02129
- Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Wen-Jui Kuo
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
| | - Iiro P Jääskeläinen
- Brain and Mind Laboratory, Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Espoo, FI-00076 AALTO, Finland
- International Laboratory of Social Neurobiology, Institute of Cognitive Neuroscience, Higher School of Economics, Moscow 101000, Russia
| | - Fa-Hsuan Lin
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario M4N 3M5, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
- Brain and Mind Laboratory, Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Espoo, FI-00076 AALTO, Finland
| |
Collapse
|
9
|
Tauber JM, Brincat SL, Stephen EP, Donoghue JA, Kozachkov L, Brown EN, Miller EK. Propofol-mediated Unconsciousness Disrupts Progression of Sensory Signals through the Cortical Hierarchy. J Cogn Neurosci 2024; 36:394-413. [PMID: 37902596 PMCID: PMC11161138 DOI: 10.1162/jocn_a_02081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
A critical component of anesthesia is the loss of sensory perception. Propofol is the most widely used drug for general anesthesia, but the neural mechanisms of how and when it disrupts sensory processing are not fully understood. We analyzed local field potential and spiking recorded from Utah arrays in auditory cortex, associative cortex, and cognitive cortex of nonhuman primates before and during propofol-mediated unconsciousness. Sensory stimuli elicited robust and decodable stimulus responses and triggered periods of stimulus-related synchronization between brain areas in the local field potential of Awake animals. By contrast, propofol-mediated unconsciousness eliminated stimulus-related synchrony and drastically weakened stimulus responses and information in all brain areas except for auditory cortex, where responses and information persisted. However, we found stimuli occurring during spiking Up states triggered weaker spiking responses than in Awake animals in auditory cortex, and little or no spiking responses in higher order areas. These results suggest that propofol's effect on sensory processing is not just because of asynchronous Down states. Rather, both Down states and Up states reflect disrupted dynamics.
Collapse
Affiliation(s)
- John M Tauber
- Massachusetts Institute of Technology, Cambridge, MA
| | | | | | | | - Leo Kozachkov
- Massachusetts Institute of Technology, Cambridge, MA
| | - Emery N Brown
- Massachusetts Institute of Technology, Cambridge, MA
- Massachusetts General Hospital, Boston
- Harvard University, Cambridge, MA
| | - Earl K Miller
- Massachusetts Institute of Technology, Cambridge, MA
| |
Collapse
|
10
|
Li B, Ma C, Huang YA, Ding X, Silverman D, Chen C, Darmohray D, Lu L, Liu S, Montaldo G, Urban A, Dan Y. Circuit mechanism for suppression of frontal cortical ignition during NREM sleep. Cell 2023; 186:5739-5750.e17. [PMID: 38070510 DOI: 10.1016/j.cell.2023.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 09/06/2023] [Accepted: 11/09/2023] [Indexed: 12/24/2023]
Abstract
Conscious perception is greatly diminished during sleep, but the underlying circuit mechanism is poorly understood. We show that cortical ignition-a brain process shown to be associated with conscious awareness in humans and non-human primates-is strongly suppressed during non-rapid-eye-movement (NREM) sleep in mice due to reduced cholinergic modulation and rapid inhibition of cortical responses. Brain-wide functional ultrasound imaging and cell-type-specific calcium imaging combined with optogenetics showed that activity propagation from visual to frontal cortex is markedly reduced during NREM sleep due to strong inhibition of frontal pyramidal neurons. Chemogenetic activation and inactivation of basal forebrain cholinergic neurons powerfully increased and decreased visual-to-frontal activity propagation, respectively. Furthermore, although multiple subtypes of dendrite-targeting GABAergic interneurons in the frontal cortex are more active during wakefulness, soma-targeting parvalbumin-expressing interneurons are more active during sleep. Chemogenetic manipulation of parvalbumin interneurons showed that sleep/wake-dependent cortical ignition is strongly modulated by perisomatic inhibition of pyramidal neurons.
Collapse
Affiliation(s)
- Bing Li
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Chenyan Ma
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Yun-An Huang
- Neuro-Electronics Research Flanders, VIB, Department of Neurosciences, KU Leuven, imec, Leuven, Belgium
| | - Xinlu Ding
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Daniel Silverman
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Changwan Chen
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Dana Darmohray
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Lihui Lu
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Siqi Liu
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Gabriel Montaldo
- Neuro-Electronics Research Flanders, VIB, Department of Neurosciences, KU Leuven, imec, Leuven, Belgium
| | - Alan Urban
- Neuro-Electronics Research Flanders, VIB, Department of Neurosciences, KU Leuven, imec, Leuven, Belgium
| | - Yang Dan
- Division of Neurobiology, Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
| |
Collapse
|
11
|
Andrillon T, Oudiette D. What is sleep exactly? Global and local modulations of sleep oscillations all around the clock. Neurosci Biobehav Rev 2023; 155:105465. [PMID: 37972882 DOI: 10.1016/j.neubiorev.2023.105465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 09/29/2023] [Accepted: 11/10/2023] [Indexed: 11/19/2023]
Abstract
Wakefulness, non-rapid eye-movement (NREM) and rapid eye-movement (REM) sleep differ from each other along three dimensions: behavioral, phenomenological, physiological. Although these dimensions often fluctuate in step, they can also dissociate. The current paradigm that views sleep as made of global NREM and REM states fail to account for these dissociations. This conundrum can be dissolved by stressing the existence and significance of the local regulation of sleep. We will review the evidence in animals and humans, healthy and pathological brains, showing different forms of local sleep and the consequences on behavior, cognition, and subjective experience. Altogether, we argue that the notion of local sleep provides a unified account for a host of phenomena: dreaming in REM and NREM sleep, NREM and REM parasomnias, intrasleep responsiveness, inattention and mind wandering in wakefulness. Yet, the physiological origins of local sleep or its putative functions remain unclear. Exploring further local sleep could provide a unique and novel perspective on how and why we sleep.
Collapse
Affiliation(s)
- Thomas Andrillon
- Paris Brain Institute, Sorbonne Université, Inserm-CNRS, Paris 75013, France; Monash Centre for Consciousness & Contemplative Studies, Monash University, Melbourne, VIC 3800, Australia.
| | - Delphine Oudiette
- Paris Brain Institute, Sorbonne Université, Inserm-CNRS, Paris 75013, France
| |
Collapse
|
12
|
Aru J, Larkum ME, Shine JM. The feasibility of artificial consciousness through the lens of neuroscience. Trends Neurosci 2023; 46:1008-1017. [PMID: 37863713 DOI: 10.1016/j.tins.2023.09.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/23/2023] [Accepted: 09/27/2023] [Indexed: 10/22/2023]
Abstract
Interactions with large language models (LLMs) have led to the suggestion that these models may soon be conscious. From the perspective of neuroscience, this position is difficult to defend. For one, the inputs to LLMs lack the embodied, embedded information content characteristic of our sensory contact with the world around us. Secondly, the architectures of present-day artificial intelligence algorithms are missing key features of the thalamocortical system that have been linked to conscious awareness in mammals. Finally, the evolutionary and developmental trajectories that led to the emergence of living conscious organisms arguably have no parallels in artificial systems as envisioned today. The existence of living organisms depends on their actions and their survival is intricately linked to multi-level cellular, inter-cellular, and organismal processes culminating in agency and consciousness.
Collapse
Affiliation(s)
- Jaan Aru
- Institute of Computer Science, University of Tartu, Tartu, Estonia.
| | - Matthew E Larkum
- Institute of Biology, Humboldt University Berlin, Berlin, Germany.
| | - James M Shine
- Brain and Mind Center, The University of Sydney, Sydney, Australia.
| |
Collapse
|
13
|
Salgado-Puga K, Rothschild G. Exposure to sounds during sleep impairs hippocampal sharp wave ripples and memory consolidation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.22.568283. [PMID: 38045371 PMCID: PMC10690295 DOI: 10.1101/2023.11.22.568283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Sleep is critical for the consolidation of recent experiences into long-term memories. As a key underlying neuronal mechanism, hippocampal sharp-wave ripples (SWRs) occurring during sleep define periods of hippocampal reactivation of recent experiences and have been causally linked with memory consolidation. Hippocampal SWR-dependent memory consolidation during sleep is often referred to as occurring during an "offline" state, dedicated to processing internally generated neural activity patterns rather than external stimuli. However, the brain is not fully disconnected from the environment during sleep. In particular, sounds heard during sleep are processed by a highly active auditory system which projects to brain regions in the medial temporal lobe, reflecting an anatomical pathway for sound modulation of hippocampal activity. While neural processing of salient sounds during sleep, such as those of a predator or an offspring, is evolutionarily adaptive, whether ongoing processing of environmental sounds during sleep interferes with SWR-dependent memory consolidation remains unknown. To address this question, we used a closed-loop system to deliver non-waking sound stimuli during or following SWRs in sleeping rats. We found that exposure to sounds during sleep suppressed the ripple power and reduced the rate of SWRs. Furthermore, sounds delivered during SWRs (On-SWR) suppressed ripple power significantly more than sounds delivered 2 seconds after SWRs (Off-SWR). Next, we tested the influence of sound presentation during sleep on memory consolidation. To this end, SWR-triggered sounds were applied during sleep sessions following learning of a conditioned place preference paradigm, in which rats learned a place-reward association. We found that On-SWR sound pairing during post-learning sleep induced a complete abolishment of memory retention 24 h following learning, while leaving memory retention immediately following sleep intact. In contrast, Off-SWR pairing weakened memory 24 h following learning as well as immediately following learning. Notably, On-SWR pairing induced a significantly larger impairment in memory 24 h after learning as compared to Off-SWR pairing. Together, these findings suggest that sounds heard during sleep suppress SWRs and memory consolidation, and that the magnitude of these effects are dependent on sound-SWR timing. These results suggest that exposure to environmental sounds during sleep may pose a risk for memory consolidation processes.
Collapse
|
14
|
Liu J, Xia T, Chen D, Yao Z, Zhu M, Antony JW, Lee TMC, Hu X. Item-specific neural representations during human sleep support long-term memory. PLoS Biol 2023; 21:e3002399. [PMID: 37983253 PMCID: PMC10695382 DOI: 10.1371/journal.pbio.3002399] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/04/2023] [Accepted: 10/20/2023] [Indexed: 11/22/2023] Open
Abstract
Understanding how individual memories are reactivated during sleep is essential in theorizing memory consolidation. Here, we employed the targeted memory reactivation (TMR) paradigm to unobtrusively replaying auditory memory cues during human participants' slow-wave sleep (SWS). Using representational similarity analysis (RSA) on cue-elicited electroencephalogram (EEG), we found temporally segregated and functionally distinct item-specific neural representations: the early post-cue EEG activity (within 0 to 2,000 ms) contained comparable item-specific representations for memory cues and control cues, signifying effective processing of auditory cues. Critically, the later EEG activity (2,500 to 2,960 ms) showed greater item-specific representations for post-sleep remembered items than for forgotten and control cues, indicating memory reprocessing. Moreover, these later item-specific neural representations were supported by concurrently increased spindles, particularly for items that had not been tested prior to sleep. These findings elucidated how external memory cues triggered item-specific neural representations during SWS and how such representations were linked to successful long-term memory. These results will benefit future research aiming to perturb specific memory episodes during sleep.
Collapse
Affiliation(s)
- Jing Liu
- Department of Applied Social Sciences, The Hong Kong Polytechnic University, Hong Kong, People’s Republic of China
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Tao Xia
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Danni Chen
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Ziqing Yao
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Minrui Zhu
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - James W. Antony
- Department of Psychology & Child Development, California Polytechnic State University, San Luis Obispo, California, United States of America
| | - Tatia M. C. Lee
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
- Laboratory of Neuropsychology and Human Neuroscience, Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
| | - Xiaoqing Hu
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Psychology, The University of Hong Kong, Hong Kong, People’s Republic of China
- HKU-Shenzhen Institute of Research and Innovation, Shenzhen, People’s Republic of China
| |
Collapse
|
15
|
Bressler S, Neely R, Yost RM, Wang D, Read HL. A wearable EEG system for closed-loop neuromodulation of sleep-related oscillations. J Neural Eng 2023; 20:056030. [PMID: 37726002 DOI: 10.1088/1741-2552/acfb3b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 09/19/2023] [Indexed: 09/21/2023]
Abstract
Objective.Healthy sleep plays a critical role in general well-being. Enhancement of slow-wave sleep by targeting acoustic stimuli to particular phases of delta (0.5-2 Hz) waves has shown promise as a non-invasive approach to improve sleep quality. Closed-loop stimulation during other sleep phases targeting oscillations at higher frequencies such as theta (4-7 Hz) or alpha (8-12 Hz) could be another approach to realize additional health benefits. However, systems to track and deliver stimulation relative to the instantaneous phase of electroencephalogram (EEG) signals at these higher frequencies have yet to be demonstrated outside of controlled laboratory settings.Approach.Here we examine the feasibility of using an endpoint-corrected version of the Hilbert transform (ecHT) algorithm implemented on a headband wearable device to measure alpha phase and deliver phase-locked auditory stimulation during the transition from wakefulness to sleep, during which alpha power is greatest. First, the ecHT algorithm is implementedin silicoto evaluate the performance characteristics of this algorithm across a range of sleep-related oscillatory frequencies. Secondly, a pilot sleep study tests feasibility to use the wearable device by users in the home setting for measurement of EEG activity during sleep and delivery of real-time phase-locked stimulation.Main results.The ecHT is capable of computing the instantaneous phase of oscillating signals with high precision, allowing auditory stimulation to be delivered at the intended phases of neural oscillations with low phase error. The wearable system was capable of measuring sleep-related neural activity with sufficient fidelity for sleep stage scoring during the at-home study, and phase-tracking performance matched simulated results. Users were able to successfully operate the system independently using the companion smartphone app to collect data and administer stimulation, and presentation of auditory stimuli during sleep initiation did not negatively impact sleep onset.Significance.This study demonstrates the feasibility of closed-loop real-time tracking and neuromodulation of a range of sleep-related oscillations using a wearable EEG device. Preliminary results suggest that this approach could be used to deliver non-invasive neuromodulation across all phases of sleep.
Collapse
Affiliation(s)
- Scott Bressler
- Elemind Technologies, Inc., Cambridge, MA, United States of America
| | - Ryan Neely
- Elemind Technologies, Inc., Cambridge, MA, United States of America
| | - Ryan M Yost
- Elemind Technologies, Inc., Cambridge, MA, United States of America
| | - David Wang
- Elemind Technologies, Inc., Cambridge, MA, United States of America
| | - Heather L Read
- Department of Psychological Sciences-Behavioral Neuroscience Division, University of Connecticut, Storrs, CT, United States of America
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, United States of America
- Brain-Computer Interface Core, University of Connecticut, Storrs, CT, United States of America
| |
Collapse
|
16
|
Andelman-Gur MM, Fried I. Consciousness: a neurosurgical perspective. Acta Neurochir (Wien) 2023; 165:2729-2735. [PMID: 37594639 DOI: 10.1007/s00701-023-05738-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 07/24/2023] [Indexed: 08/19/2023]
Abstract
Neurosurgeons are in a unique position to shed light on the neural basis for consciousness, not only by their clinical care of patients with compromised states of consciousness, but also by employing neurostimulation and neuronal recordings through intracranial electrodes in awake surgical patients, as well as during stages of sleep and anethesia. In this review, we discuss several aspects of consciousness, i.e., perception, memory, and willed actions, studied by electrical stimulation and single neuron recordings in the human brain. We demonstrate how specific neuronal activity underlie the emergence of concepts, memories, and intentions in human consciousness. We discuss the representation of specific conscious content by temporal lobe neurons and present the discovery of "concept cells" and the encoding and retrieval of memories by neurons in the medial temporal lobe. We review prefrontal and parietal neuronal activation that precedes conscious intentions to act. Taken together with other studies in the field, these findings suggest that specific conscious experience may arise from stochastic fluctuations of neuronal activity, reaching a dynamic threshold. Advances in brain recording and stimulation technology coupled with the rapid rise in artificial intelligence are likely to increase the amount and analysis capabilities of data obtained from the human brain, thereby improving the decoding of conscious and preconscious states and open new horizons for modulation of human cognitive functions such as memory and volition.
Collapse
Affiliation(s)
| | - Itzhak Fried
- Department of Neurosurgery, David Geffen School of Medicine and Semel Institute for Neuroscience and Human Behavior, University of California, 300 Stein Plaza, Ste. 562, Los Angeles, CA, USA.
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
| |
Collapse
|
17
|
Banks MI, Krause BM, Berger DG, Campbell DI, Boes AD, Bruss JE, Kovach CK, Kawasaki H, Steinschneider M, Nourski KV. Functional geometry of auditory cortical resting state networks derived from intracranial electrophysiology. PLoS Biol 2023; 21:e3002239. [PMID: 37651504 PMCID: PMC10499207 DOI: 10.1371/journal.pbio.3002239] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 09/13/2023] [Accepted: 07/07/2023] [Indexed: 09/02/2023] Open
Abstract
Understanding central auditory processing critically depends on defining underlying auditory cortical networks and their relationship to the rest of the brain. We addressed these questions using resting state functional connectivity derived from human intracranial electroencephalography. Mapping recording sites into a low-dimensional space where proximity represents functional similarity revealed a hierarchical organization. At a fine scale, a group of auditory cortical regions excluded several higher-order auditory areas and segregated maximally from the prefrontal cortex. On mesoscale, the proximity of limbic structures to the auditory cortex suggested a limbic stream that parallels the classically described ventral and dorsal auditory processing streams. Identities of global hubs in anterior temporal and cingulate cortex depended on frequency band, consistent with diverse roles in semantic and cognitive processing. On a macroscale, observed hemispheric asymmetries were not specific for speech and language networks. This approach can be applied to multivariate brain data with respect to development, behavior, and disorders.
Collapse
Affiliation(s)
- Matthew I. Banks
- Department of Anesthesiology, University of Wisconsin, Madison, Wisconsin, United States of America
- Department of Neuroscience, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Bryan M. Krause
- Department of Anesthesiology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - D. Graham Berger
- Department of Anesthesiology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Declan I. Campbell
- Department of Anesthesiology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Aaron D. Boes
- Department of Neurology, The University of Iowa, Iowa City, Iowa, United States of America
| | - Joel E. Bruss
- Department of Neurology, The University of Iowa, Iowa City, Iowa, United States of America
| | - Christopher K. Kovach
- Department of Neurosurgery, The University of Iowa, Iowa City, Iowa, United States of America
| | - Hiroto Kawasaki
- Department of Neurosurgery, The University of Iowa, Iowa City, Iowa, United States of America
| | - Mitchell Steinschneider
- Department of Neurology, Albert Einstein College of Medicine, New York, New York, United States of America
- Department of Neuroscience, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Kirill V. Nourski
- Department of Neurosurgery, The University of Iowa, Iowa City, Iowa, United States of America
- Iowa Neuroscience Institute, The University of Iowa, Iowa City, Iowa, United States of America
| |
Collapse
|
18
|
Das A, Menon V. Concurrent- and After-Effects of Medial Temporal Lobe Stimulation on Directed Information Flow to and from Prefrontal and Parietal Cortices during Memory Formation. J Neurosci 2023; 43:3159-3175. [PMID: 36963847 PMCID: PMC10146497 DOI: 10.1523/jneurosci.1728-22.2023] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 03/06/2023] [Accepted: 03/13/2023] [Indexed: 03/26/2023] Open
Abstract
Electrical stimulation of the medial temporal lobe (MTL) has the potential to uncover causal circuit mechanisms underlying memory function. However, little is known about how MTL stimulation alters information flow with frontoparietal cortical regions implicated in episodic memory. We used intracranial EEG recordings from humans (14 participants, 10 females) to investigate how MTL stimulation alters directed information flow between MTL and PFC and between MTL and posterior parietal cortex (PPC). Participants performed a verbal episodic memory task during which they were presented with words and asked to recall them after a delay of ∼20 s; 50 Hz stimulation was applied to MTL electrodes on selected trials during memory encoding. Directed information flow was examined using phase transfer entropy. Behaviorally, we observed that MTL stimulation reduced memory recall. MTL stimulation decreased top-down PFC→MTL directed information flow during both memory encoding and subsequent memory recall, revealing aftereffects more than 20 s after end of stimulation. Stimulation suppressed top-down PFC→MTL influences to a greater extent than PPC→MTL. Finally, MTL→PFC information flow on stimulation trials was significantly lower for successful, compared with unsuccessful, memory recall; in contrast, MTL→ventral PPC information flow was higher for successful, compared with unsuccessful, memory recall. Together, these results demonstrate that the effects of MTL stimulation are behaviorally, regionally, and directionally specific, that MTL stimulation selectively impairs directional signaling with PFC, and that causal MTL-ventral PPC circuits support successful memory recall. Findings provide new insights into dynamic casual circuits underling episodic memory and their modulation by MTL stimulation.SIGNIFICANCE STATEMENT The medial temporal lobe (MTL) and its interactions with prefrontal and parietal cortices (PFC and PPC) play a critical role in human memory. Dysfunctional MTL-PFC and MTL-PPC circuits are prominent in psychiatric and neurologic disorders, including Alzheimer's disease and schizophrenia. Brain stimulation has emerged as a potential mechanism for enhancing memory and cognitive functions, but the underlying neurophysiological mechanisms and dynamic causal circuitry underlying bottom-up and top-down signaling involving the MTL are unknown. Here, we use intracranial EEG recordings to investigate the effects of MTL stimulation on causal signaling in key episodic memory circuits linking the MTL with PFC and PPC. Our findings have implications for translational applications aimed at realizing the promise of brain stimulation-based treatment of memory disorders.
Collapse
Affiliation(s)
- Anup Das
- Department of Psychiatry & Behavioral Sciences
| | - Vinod Menon
- Department of Psychiatry & Behavioral Sciences
- Department of Neurology & Neurological Sciences
- Stanford Neurosciences Institute, Stanford University School of Medicine, Stanford, California 94305
| |
Collapse
|
19
|
Westlin C, Theriault JE, Katsumi Y, Nieto-Castanon A, Kucyi A, Ruf SF, Brown SM, Pavel M, Erdogmus D, Brooks DH, Quigley KS, Whitfield-Gabrieli S, Barrett LF. Improving the study of brain-behavior relationships by revisiting basic assumptions. Trends Cogn Sci 2023; 27:246-257. [PMID: 36739181 PMCID: PMC10012342 DOI: 10.1016/j.tics.2022.12.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 12/23/2022] [Accepted: 12/29/2022] [Indexed: 02/05/2023]
Abstract
Neuroimaging research has been at the forefront of concerns regarding the failure of experimental findings to replicate. In the study of brain-behavior relationships, past failures to find replicable and robust effects have been attributed to methodological shortcomings. Methodological rigor is important, but there are other overlooked possibilities: most published studies share three foundational assumptions, often implicitly, that may be faulty. In this paper, we consider the empirical evidence from human brain imaging and the study of non-human animals that calls each foundational assumption into question. We then consider the opportunities for a robust science of brain-behavior relationships that await if scientists ground their research efforts in revised assumptions supported by current empirical evidence.
Collapse
Affiliation(s)
| | - Jordan E Theriault
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Yuta Katsumi
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Alfonso Nieto-Castanon
- Department of Speech, Language, and Hearing Sciences, Boston University, Boston, MA, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Aaron Kucyi
- Department of Psychological and Brain Sciences, Drexel University, Philadelphia, PA, USA
| | - Sebastian F Ruf
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
| | - Sarah M Brown
- Department of Computer Science and Statistics, University of Rhode Island, Kingston, RI, USA
| | - Misha Pavel
- Khoury College of Computer Sciences, Northeastern University, Boston, MA, USA; Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA
| | - Deniz Erdogmus
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, USA
| | - Dana H Brooks
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, USA
| | - Karen S Quigley
- Department of Psychology, Northeastern University, Boston, MA, USA
| | | | - Lisa Feldman Barrett
- Department of Psychology, Northeastern University, Boston, MA, USA; A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
| |
Collapse
|