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Liu Y, Xu T, Yu Z, Xu B. Neurophysiological Basis of Electroacupuncture Stimulation in the Treatment of Cardiovascular-Related Diseases: Vagal Interoceptive Loops. Brain Behav 2024; 14:e70076. [PMID: 39344397 DOI: 10.1002/brb3.70076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 08/28/2024] [Accepted: 09/07/2024] [Indexed: 10/01/2024] Open
Abstract
PURPOSE The vagal sensory nerve (VSN) is an essential interoceptive pathway that is connected to every level of the body. Its intricate genetic coding provides sustenance for physiological processes, including controlling blood pressure and respiration. Electroacupuncture (EA) is a proven surface stimulation therapy that can regulate vagal nerve activity, which can effectively prevent cardiovascular diseases. A growing number of studies have concentrated on the mapping of VSN codes, but little is known, and the physiological background of how EA influences interoceptive has not been fully explored. METHOD Here, we incorporate the hypothesized interaction among EA targets, VSNs, and the heart. This offers suggestions for using a versatile and focused EA strategy to modify vagal interoceptive awareness to enhance cardiovascular conditions. We first clarified the major role of vagal nerve in the control of cardiac activity. Additionally, we clarified the multidimensional coding pattern in the VSNs, revealing that the targeted control of multimodal interoceptive is the functional basis of the synchronization of cardiovascular system. FINDING We propose a strategy in which EA of the VSNs is employed to activate the interoceptive loop and reduce the risk of cardiovascular disease.
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Affiliation(s)
- Yun Liu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Tiancheng Xu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Zhi Yu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
| | - Bin Xu
- Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China
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Nagai M, Dote K, Kato M, Sasaki S, Oda N, Po SS, Dasari TW. Blood Pressure Variability After Non-invasive Low-level Tragus Stimulation in Acute Heart Failure. J Cardiovasc Transl Res 2024:10.1007/s12265-024-10544-4. [PMID: 38969912 DOI: 10.1007/s12265-024-10544-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2024] [Accepted: 07/01/2024] [Indexed: 07/07/2024]
Abstract
Higher blood pressure (BP) variability (BPV) was shown to be strong predictors of poor cardiovascular outcomes in heart failure (HF). It is currently unknown if low-level tragus stimulation (LLTS) would lead to improvement in BPV in acute HF (AHF). The 22 patients with AHF (median 80 yrs, males 60%) were randomly assigned to active or sham group using an ear clip attached to the tragus (active group) or the earlobe (sham group) for 1 h daily over 5 days. In the active group, standard deviation (SD), coefficient of variation (CV) and δ in SBP were significantly decreased after LLTS (all p < 0.05). All the changes in SD, CV and δ in SBP before and after stimulation were also significantly different between active and sham groups (all p < 0.05). This proof-of-concept study demonstrates the beneficial effects of LLTS on BPV in AHF.
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Affiliation(s)
- Michiaki Nagai
- Department of Cardiology, Hiroshima City Asa Hospital, Hiroshima, Japan.
- Cardiovascular Section, Department of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK, USA.
| | - Keigo Dote
- Department of Cardiology, Hiroshima City Asa Hospital, Hiroshima, Japan
| | - Masaya Kato
- Department of Cardiology, Hiroshima City Asa Hospital, Hiroshima, Japan
| | - Shota Sasaki
- Department of Cardiology, Hiroshima City Asa Hospital, Hiroshima, Japan
| | - Noboru Oda
- Department of Cardiology, Hiroshima City Asa Hospital, Hiroshima, Japan
| | - Sunny S Po
- Cardiovascular Section, Department of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK, USA
| | - Tarun W Dasari
- Cardiovascular Section, Department of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK, USA.
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Tan G, Adams J, Donovan K, Demarest P, Willie JT, Brunner P, Gorlewicz JL, Leuthardt EC. Does Vibrotactile Stimulation of the Auricular Vagus Nerve Enhance Working Memory? A Behavioral and Physiological Investigation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.24.586365. [PMID: 38585960 PMCID: PMC10996508 DOI: 10.1101/2024.03.24.586365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Background Working memory is essential to a wide range of cognitive functions and activities. Transcutaneous auricular VNS (taVNS) is a promising method to improve working memory performance. However, the feasibility and scalability of electrical stimulation are constrained by several limitations, such as auricular discomfort and inconsistent electrical contact. Objective We aimed to develop a novel and practical method, vibrotactile taVNS, to improve working memory. Further, we investigated its effects on arousal, measured by skin conductance and pupil diameter. Method This study included 20 healthy participants. Behavioral response, skin conductance, and eye tracking data were concurrently recorded while the participants performed N-back tasks under three conditions: vibrotactile taVNS delivered to the cymba concha, earlobe (sham control), and no stimulation (baseline control). Results In 4-back tasks, which demand maximal working memory capacity, active vibrotactile taVNS significantly improved the performance metric d ' compared to the baseline but not to the sham. Moreover, we found that the reduction rate of d ' with increasing task difficulty was significantly smaller during vibrotactile taVNS sessions than in both baseline and sham conditions. Arousal, measured as skin conductance and pupil diameter, declined over the course of the tasks. Vibrotactile taVNS rescued this arousal decline, leading to arousal levels corresponding to optimal working memory levels. Moreover, pupil diameter and skin conductance level were higher during high-cognitive-load tasks when vibrotactile taVNS was delivered to the concha compared to baseline and sham. Conclusion Our findings suggest that vibrotactile taVNS modulates the arousal pathway and could be a potential intervention for enhancing working memory. Highlights Vibrotactile stimulation of the auricular vagus nerve increases general arousal.Vibrotactile stimulation of the auricular vagus nerve mitigates arousal decreases as subjects continuously perform working memory tasks.6 Hz Vibrotactile auricular vagus nerve stimulation is a potential intervention for enhancing working memory performance.
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Rajendran PS, Hadaya J, Khalsa SS, Yu C, Chang R, Shivkumar K. The vagus nerve in cardiovascular physiology and pathophysiology: From evolutionary insights to clinical medicine. Semin Cell Dev Biol 2024; 156:190-200. [PMID: 36641366 PMCID: PMC10336178 DOI: 10.1016/j.semcdb.2023.01.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 01/01/2023] [Accepted: 01/03/2023] [Indexed: 01/13/2023]
Abstract
The parasympathetic nervous system via the vagus nerve exerts profound influence over the heart. Together with the sympathetic nervous system, the parasympathetic nervous system is responsible for fine-tuned regulation of all aspects of cardiovascular function, including heart rate, rhythm, contractility, and blood pressure. In this review, we highlight vagal efferent and afferent innervation of the heart, with a focus on insights from comparative biology and advances in understanding the molecular and genetic diversity of vagal neurons, as well as interoception, parasympathetic dysfunction in heart disease, and the therapeutic potential of targeting the parasympathetic nervous system in cardiovascular disease.
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Affiliation(s)
| | - Joseph Hadaya
- University of California, Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; UCLA Molecular, Cellular, and Integrative Physiology Program, Los Angeles, CA, USA
| | - Sahib S Khalsa
- Laureate Institute for Brain Research, Tulsa, Ok, USA; Oxley College of Health Sciences, University of Tulsa, Tulsa, Ok, USA
| | - Chuyue Yu
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
| | - Rui Chang
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
| | - Kalyanam Shivkumar
- University of California, Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; UCLA Molecular, Cellular, and Integrative Physiology Program, Los Angeles, CA, USA.
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Tan G, Adams J, Donovan K, Demarest P, Willie JT, Brunner P, Gorlewicz JL, Leuthardt EC. Does vibrotactile stimulation of the auricular vagus nerve enhance working memory? A behavioral and physiological investigation. Brain Stimul 2024; 17:460-468. [PMID: 38593972 PMCID: PMC11268363 DOI: 10.1016/j.brs.2024.04.002] [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] [Received: 11/07/2023] [Revised: 03/22/2024] [Accepted: 04/02/2024] [Indexed: 04/11/2024] Open
Abstract
BACKGROUND Working memory is essential to a wide range of cognitive functions and activities. Transcutaneous auricular vagus nerve stimulation (taVNS) is a promising method to improve working memory performance. However, the feasibility and scalability of electrical stimulation are constrained by several limitations, such as auricular discomfort and inconsistent electrical contact. OBJECTIVE We aimed to develop a novel and practical method, vibrotactile taVNS, to improve working memory. Further, we investigated its effects on arousal, measured by skin conductance and pupil diameter. METHOD This study included 20 healthy participants. Behavioral response, skin conductance, and eye tracking data were concurrently recorded while the participants performed N-back tasks under three conditions: vibrotactile taVNS delivered to the cymba concha, earlobe (sham control), and no stimulation (baseline control). RESULTS In 4-back tasks, which demand maximal working memory capacity, active vibrotactile taVNS significantly improved the performance metric d' compared to the baseline but not to the sham. Moreover, we found that the reduction rate of d' with increasing task difficulty was significantly smaller during vibrotactile taVNS sessions than in both baseline and sham conditions. Arousal, measured as skin conductance and pupil diameter, declined over the course of the tasks. Vibrotactile taVNS rescued this arousal decline, leading to arousal levels corresponding to optimal working memory levels. Moreover, pupil diameter and skin conductance level were higher during high-cognitive-load tasks when vibrotactile taVNS was delivered to the concha compared to baseline and sham. CONCLUSION Our findings suggest that vibrotactile taVNS modulates the arousal pathway and could be a potential intervention for enhancing working memory.
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Affiliation(s)
- Gansheng Tan
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University in St. Louis, MO, USA; Division of Neurotechnology, Washington University School of Medicine, St. Louis, MO, USA
| | - Josh Adams
- Department of Aerospace and Mechanical Engineering, Saint Louis University, MO, USA
| | - Kara Donovan
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University in St. Louis, MO, USA; Division of Neurotechnology, Washington University School of Medicine, St. Louis, MO, USA
| | - Phillip Demarest
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University in St. Louis, MO, USA; Division of Neurotechnology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jon T Willie
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University in St. Louis, MO, USA; Department of Neuroscience, Washington University in St. Louis, MO, USA; Division of Neurotechnology, Washington University School of Medicine, St. Louis, MO, USA
| | - Peter Brunner
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University in St. Louis, MO, USA; Division of Neurotechnology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jenna L Gorlewicz
- Department of Aerospace and Mechanical Engineering, Saint Louis University, MO, USA
| | - Eric C Leuthardt
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University in St. Louis, MO, USA; Department of Neuroscience, Washington University in St. Louis, MO, USA; Division of Neurotechnology, Washington University School of Medicine, St. Louis, MO, USA.
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Ventura‐Bort C, Weymar M. Transcutaneous auricular vagus nerve stimulation modulates the processing of interoceptive prediction error signals and their role in allostatic regulation. Hum Brain Mapp 2024; 45:e26613. [PMID: 38379451 PMCID: PMC10879907 DOI: 10.1002/hbm.26613] [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: 08/17/2023] [Revised: 01/03/2024] [Accepted: 01/18/2024] [Indexed: 02/22/2024] Open
Abstract
It has recently been suggested that predictive processing principles may apply to interoception, defined as the processing of hormonal, autonomic, visceral, and immunological signals. In the current study, we aimed at providing empirical evidence for the role of cardiac interoceptive prediction errors signals on allostatic adjustments, using transcutaneous auricular vagus nerve stimulation (taVNS) as a tool to modulate the processing of interoceptive afferents. In a within-subject design, participants performed a cardiac-related interoceptive task (heartbeat counting task) under taVNS and sham stimulation, spaced 1-week apart. We observed that taVNS, in contrast to sham stimulation, facilitated the maintenance of interoceptive accuracy levels over time (from the initial, stimulation-free, baseline block to subsequent stimulation blocks), suggesting that vagus nerve stimulation may have helped to maintain engagement to cardiac afferent signals. During the interoceptive task, taVNS compared to sham, produced higher heart-evoked potentials (HEP) amplitudes, a potential readout measure of cardiac-related prediction error processing. Further analyses revealed that the positive relation between interoceptive accuracy and allostatic adjustments-as measured by heart rate variability (HRV)-was mediated by HEP amplitudes. Providing initial support for predictive processing accounts of interoception, our results suggest that the stimulation of the vagus nerve may increase the precision with which interoceptive signals are processed, favoring their influence on allostatic adjustments.
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Affiliation(s)
- Carlos Ventura‐Bort
- Department of Biological Psychology and Affective Science, Faculty of Human SciencesUniversity of PotsdamPotsdamGermany
| | - Mathias Weymar
- Department of Biological Psychology and Affective Science, Faculty of Human SciencesUniversity of PotsdamPotsdamGermany
- Faculty of Health Sciences BrandenburgUniversity of PotsdamPotsdamGermany
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Liu H, Liang H, Yu X, Wang G, Han Y, Yan M, Li S, Wang W. Enhanced external counterpulsation modulates the heartbeat evoked potential. Front Physiol 2023; 14:1144073. [PMID: 37078023 PMCID: PMC10106756 DOI: 10.3389/fphys.2023.1144073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 03/23/2023] [Indexed: 04/05/2023] Open
Abstract
Introduction: Accumulating evidence suggests that enhanced external counterpulsation (EECP) influences cardiac functions, hemodynamic characteristics and cerebral blood flow. However, little is known about whether or how the EECP affects the brain-heart coupling to produce these physiological and functional changes. We aimed to determine if the brain-heart coupling is altered during or after EECP intervention by assessing the heartbeat evoked potential (HEP) in healthy adults.Methods: Based on a random sham-controlled design, simultaneous electroencephalography and electrocardiography signals as well as blood pressure and flow status data were recorded before, during and after two consecutive 30-min EECP in 40 healthy adults (female/male: 17/23; age: 23.1 ± 2.3 years). HEP amplitude, frequency domain heart rate variability, electroencephalographic power and hemodynamic measurements of 21 subjects (female/male: 10/11; age: 22.7 ± 2.1 years) receiving active EECP were calculated and compared with those of 19 sham control subjects (female/male: 7/12; age: 23.6 ± 2.5 years).Results: EECP intervention caused immediate obvious fluctuations of HEP from 100 to 400 ms after T-peak and increased HEP amplitudes in the (155–169) ms, (354–389) ms and (367–387) ms time windows after T-peak in the region of the frontal pole lobe. The modifications in HEP amplitude were not associated with changes in the analyzed significant physiological measurements and hemodynamic variables.Discussion: Our study provides evidence that the HEP is modulated by immediate EECP stimuli. We speculate that the increased HEP induced by EECP may be a marker of enhanced brain-heart coupling. HEP may serve as a candidate biomarker for the effects and responsiveness to EECP.
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Affiliation(s)
- Hongyun Liu
- Research Center for Biomedical Engineering, Medical Innovation Research Division, Chinese PLA General Hospital, Beijing, China
- Key Laboratory of Biomedical Engineering and Translational Medicine, Ministry of Industry and Information Technology, Beijing, China
- *Correspondence: Hongyun Liu, ; Muyang Yan, ; Shijun Li, ; Weidong Wang,
| | - Hui Liang
- Department of Hyperbaric Oxygen, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Xiaohua Yu
- Research Center for Biomedical Engineering, Medical Innovation Research Division, Chinese PLA General Hospital, Beijing, China
- Key Laboratory of Biomedical Engineering and Translational Medicine, Ministry of Industry and Information Technology, Beijing, China
| | - Guojing Wang
- Research Center for Biomedical Engineering, Medical Innovation Research Division, Chinese PLA General Hospital, Beijing, China
- Key Laboratory of Biomedical Engineering and Translational Medicine, Ministry of Industry and Information Technology, Beijing, China
| | - Yi Han
- Research Center for Biomedical Engineering, Medical Innovation Research Division, Chinese PLA General Hospital, Beijing, China
- Key Laboratory of Biomedical Engineering and Translational Medicine, Ministry of Industry and Information Technology, Beijing, China
| | - Muyang Yan
- Department of Hyperbaric Oxygen, The First Medical Center, Chinese PLA General Hospital, Beijing, China
- *Correspondence: Hongyun Liu, ; Muyang Yan, ; Shijun Li, ; Weidong Wang,
| | - Shijun Li
- Department of Diagnostic Radiology, The First Medical Center, Chinese PLA General Hospital, Beijing, China
- *Correspondence: Hongyun Liu, ; Muyang Yan, ; Shijun Li, ; Weidong Wang,
| | - Weidong Wang
- Research Center for Biomedical Engineering, Medical Innovation Research Division, Chinese PLA General Hospital, Beijing, China
- Key Laboratory of Biomedical Engineering and Translational Medicine, Ministry of Industry and Information Technology, Beijing, China
- *Correspondence: Hongyun Liu, ; Muyang Yan, ; Shijun Li, ; Weidong Wang,
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Elamin ABA, Forsat K, Senok SS, Goswami N. Vagus Nerve Stimulation and Its Cardioprotective Abilities: A Systematic Review. J Clin Med 2023; 12:jcm12051717. [PMID: 36902505 PMCID: PMC10003006 DOI: 10.3390/jcm12051717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/10/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023] Open
Abstract
Despite the vagus nerve stimulator (VNS) being used in neuroscience, it has recently been highlighted that it has cardioprotective functions. However, many studies related to VNS are not mechanistic in nature. This systematic review aims to focus on the role of VNS in cardioprotective therapy, selective vagus nerve stimulators (sVNS), and their functional capabilities. A systemic review of the current literature was conducted on VNS, sVNS, and their ability to induce positive effects on arrhythmias, cardiac arrest, myocardial ischemia/reperfusion injury, and heart failure. Both experimental and clinical studies were reviewed and assessed separately. Of 522 research articles retrieved from literature archives, 35 met the inclusion criteria and were included in the review. Literature analysis proves that combining fiber-type selectivity with spatially-targeted vagus nerve stimulation is feasible. The role of VNS as a tool for modulating heart dynamics, inflammatory response, and structural cellular components was prominently seen across the literature. The application of transcutaneous VNS, as opposed to implanted electrodes, provides the best clinical outcome with minimal side effects. VNS presents a method for future cardiovascular treatment that can modulate human cardiac physiology. However, continued research is needed for further insight.
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Affiliation(s)
| | - Kowthar Forsat
- College of Medicine, Ajman University, Ajman P.O. Box 346, United Arab Emirates
| | - Solomon Silas Senok
- College of Medicine, Ajman University, Ajman P.O. Box 346, United Arab Emirates
| | - Nandu Goswami
- Institute of Physiology (Gravitational Physiology and Medicine), Medical University of Graz, 8036 Graz, Austria
- College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai P.O. Box 505055, United Arab Emirates
- Correspondence:
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Gianlorenco ACL, de Melo PS, Marduy A, Kim AY, Kim CK, Choi H, Song JJ, Fregni F. Electroencephalographic Patterns in taVNS: A Systematic Review. Biomedicines 2022; 10:2208. [PMID: 36140309 PMCID: PMC9496216 DOI: 10.3390/biomedicines10092208] [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: 06/27/2022] [Revised: 08/24/2022] [Accepted: 08/27/2022] [Indexed: 11/16/2022] Open
Abstract
Transcutaneous auricular vagus nerve stimulation (taVNS) is a newer delivery system using a non-invasive stimulation device placed at the ear. taVNS research is focused on clinical trials showing potential therapeutic benefits, however the neurophysiological effects of this stimulation on brain activity are still unclear. We propose a systematic review that aims to describe the effects of taVNS on EEG measures and identify taVNS parameters that can potentially lead to consistent EEG-mediated biomarkers for this therapy. A systematic literature review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) and the Cochrane handbook for systematic reviews. Clinical trials examining EEG parameters were considered, including absolute and relative power, coherence, degree of symmetry, evoked potentials, and peak frequency of all bands. According to our criteria, 18 studies (from 122 articles) were included. Our findings show a general trend towards increased EEG power spectrum activity in lower frequencies, and changes on early components of the ERP related to inhibitory tasks. This review suggests that quantitative electroencephalography can be used to assess the effects of taVNS on brain activity, however more studies are needed to systematically establish the specific effects and metrics that would reflect the non-invasive stimulation through the auricular branch of the vagus nerve.
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Affiliation(s)
- Anna Carolyna L. Gianlorenco
- Department of Physical Therapy, Federal University of Sao Carlos, Sao Carlos 13565-090, Brazil
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
| | - Paulo S. de Melo
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
- Medicine, Escola Bahiana de Medicina e Saúde Pública, Salvador 40290-000, Brazil
| | - Anna Marduy
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
- União Metropolitana de Ensino e Cultura (UNIME) Salvador, Salvador 42700-000, Brazil
| | - Angela Yun Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University Medical Center, Seoul 08308, Korea
| | - Chi Kyung Kim
- Department of Neurology, Korea University Guro Hospital, Seoul 08308, Korea
| | - Hyuk Choi
- Department of Medical Sciences, Graduate School of Medicine, Korea University, Seoul 08308, Korea
- Neurive Co., Ltd., Gimhae 08308, Korea
| | - Jae-Jun Song
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University Medical Center, Seoul 08308, Korea
- Neurive Co., Ltd., Gimhae 08308, Korea
| | - Felipe Fregni
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
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Yokota H, Edama M, Hirabayashi R, Sekine C, Otsuru N, Saito K, Kojima S, Miyaguchi S, Onishi H. Effects of Stimulus Frequency, Intensity, and Sex on the Autonomic Response to Transcutaneous Vagus Nerve Stimulation. Brain Sci 2022; 12:brainsci12081038. [PMID: 36009101 PMCID: PMC9405815 DOI: 10.3390/brainsci12081038] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 07/29/2022] [Accepted: 08/03/2022] [Indexed: 12/10/2022] Open
Abstract
This study aimed to determine how transcutaneous vagus nerve stimulation (tVNS) alters autonomic nervous activity by comparing the effects of different tVNS frequencies and current intensities. We also investigated the sex-dependent autonomic response to tVNS. Thirty-five healthy adult participants were stimulated using a tVNS stimulator at the left cymba conchae while sitting on a reclining chair; tVNS-induced waveform changes were then recorded for different stimulus frequencies (Experiment 1: 3.0 mA at 100 Hz, 25 Hz, 10 Hz, 1 Hz, and 0 Hz (no stimulation)) and current intensities (Experiment 2: 100 Hz at 3.0 mA, 1.0 mA, 0.2 mA (below sensory threshold), and 0 mA (no stimulation)) using an electrocardiogram. Pulse widths were set at 250 µs in both experiment 1 and 2. Changes in heart rate (HR), root-mean-square of the difference between two successive R waves (RMSSD), and the ratio between low-frequency (LF) (0.04–0.15 Hz) and high-frequency (HF) (0.15–0.40 Hz) bands (LF/HF) in spectral analysis, which indicates sympathetic and parasympathetic activity, respectively, in heart rate variability (HRV), were recorded for analysis. Although stimulation at all frequencies significantly reduced HR (p = 0.001), stimulation at 100 Hz had the most pronounced effect (p = 0.001) in Experiment 1 and was revealed to be required to deliver at 3.0 mA in Experiment 2 (p = 0.003). Additionally, participants with higher baseline sympathetic activity experienced higher parasympathetic response during stimulation, and sex differences may exist in the autonomic responses by the application of tVNS. Therefore, our findings suggest that optimal autonomic changes induced by tVNS to the left cymba conchae vary depending on stimulating parameters and sex.
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Affiliation(s)
- Hirotake Yokota
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Correspondence: ; Tel.: +81-25-257-4723
| | - Mutsuaki Edama
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
| | - Ryo Hirabayashi
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
| | - Chie Sekine
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
| | - Naofumi Otsuru
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
| | - Kei Saito
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
| | - Sho Kojima
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
| | - Shota Miyaguchi
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
| | - Hideaki Onishi
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata 950-3198, Japan
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